JPH06347994A - Halftone system phase shift mask and its correcting method and production of semiconductor device - Google Patents

Abstract

PURPOSE:To provide the halftone system phase shift mask with which a defec tive region is selectively and surely coated with a light shielding body, the difference of the transfer pattern shape after mask correction from a desired shape is practicably negligible and the defective region is corrected. CONSTITUTION:The halftone system phase shift mask 1B which has half light shielding regions 12 and light transmission regions 10 and varies in the phase of the light past the half light shielding regions and the phase of the light past the light transparent regions includes the defective regions 14 which varies in phase, amplitude transmittance or both thereof from prescribed values and exists in the half light shielding region 12 adjacent or proximate to the light transmission region 10. In addition, the correction region 16 within the defective region larger than the defective region and a part 10A of the light transmission region adjacent or proximity to the correction region 16 is coated with the light shielding body 30 having the amplitude transmittance at which a resist material is not sensitized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halftone type phase shift mask, a method of repairing the halftone type phase shift mask, and a method of manufacturing a semiconductor device using the halftone type phase shift mask.

[0002]

2. Description of the Related Art A photomask used in a pattern transfer process, that is, a so-called lithography process in manufacturing a semiconductor device is used for transferring a pattern shape on the photomask onto a resist material formed on a wafer. When a defect exists on the photomask, the defect is transferred to the resist material, so that a defect is generated in the manufactured semiconductor device, the performance of the semiconductor device is significantly impaired, and the manufacturing yield of the semiconductor device is increased. Is significantly reduced. Therefore, it is strongly required that the photomask does not contain defects that would be transferred to the resist material. Therefore,
During the photomask fabrication process, the photomask must be inspected and the detected defects corrected to remove any defects that may be transferred to the resist material.

On the other hand, the dimensions of pattern processing in semiconductor devices and the like are becoming finer year by year. A conventional photomask composed of only a light-shielding region and a light-transmitting region cannot obtain a resolution of about the wavelength of the exposure light of the exposure apparatus used in the lithography process, and is required in the manufacture of semiconductor devices and the like. It is becoming difficult to obtain high resolution. Therefore, in recent years, so-called phase shift masks having a phase shift region that makes the phase of light different have been used in place of such conventional photomasks. By using a phase shift mask, it is possible to form a fine pattern that cannot be formed by a conventional photomask. Also in such a phase shift mask, it is indispensable for practical use to remove the defect by inspecting and correcting the defect, as in the conventional photomask.

The conventional phase shift mask has a light transmitting region,
The light-shielding region for shielding light and the phase shift region made of a light-transmitting substance for transmitting light having a phase different from the phase of light passing through the light-transmitting region are provided. Typical partial cutaway views of a typical conventional edge-enhanced phase shift mask are shown in FIGS. In the figure, 20 is a substrate,
Reference numeral 10 is a light transmitting region, 18 is a light shielding region, 24 is a phase shift region, and 26 is a light transmitting material layer. The conventional phase shift mask cannot form a fine pattern unless the shape or position of the phase shift region is precisely controlled. In addition, depending on the pattern shape, the phase shift region may cause light interference even in other light transmitting regions that should not receive light interference. In such a case, the phase shift region cannot be formed.

As a kind of phase shift mask for solving the problems of the conventional phase shift mask, a semi-shielded region and a light transmission region are provided, and a phase of light passing through the semi-shielded region and a light transmission region are provided. There is a halftone type phase shift mask in which the phase of light passing through is different. In the halftone phase shift mask, the semi-shielded region is formed on the entire surface except the light transmission region. The halftone type phase shift mask has an advantage that not only the problems of the conventional phase shift mask can be solved, but also the fabrication thereof is easy, and the degree of generation of defects during mask fabrication is low. A schematic partial cutaway view of a conventional halftone phase shift mask is shown in FIG. In the figure, 20 is a substrate,
Reference numeral 10 is a light transmission area, and 12 is a semi-shielded area. The semi-shielded region 12 is composed of a semi-shielded layer 22 and a light transmission material layer 26. The light transmitting material layer 26 is made of a light transmitting material for making the phase of light passing through the light transmitting area 10 different from the phase of light passing through the semi-shielded area 12.

In the halftone phase shift mask, the amplitude transmittance of the semi-shielded region 12 is larger than 0 and does not resolve the resist material, for example, 20 to 45.
%. In addition, when expressed by light intensity transmittance, it is 4 to 2
It is about 0%. Then, in order to transfer the pattern shape formed on the mask to the resist material formed on the wafer, the semi-shielded region 1 having a predetermined amplitude transmittance and phase
The light passing through 2 and the semi-shielded region have, for example, a phase of 180.
The interference of light that has passed through different light transmission regions 10 is used. Therefore, a region different from the predetermined phase, a region different from the predetermined amplitude transmittance, or a region different from both of them becomes a defect region, and the transfer pattern shape transferred to the resist material on the wafer is a desired pattern shape. Will be different from.

Several methods have been proposed so far for the defect correction method of the halftone phase shift mask which is the object of the present invention.

One of those methods is a method of restoring a mask pattern having a defect as designed.
Examples of defects that can be corrected by this method are: (A) As shown in the schematic partial cross-sectional view of FIG. 32A, the light-transmitting material layer 26 for controlling the phase, which is provided in the semi-shielded region 12, is omitted, and the semi-shielded region 12 is exposed. A defect area 14 in which the phase of light that has passed is different from a predetermined value. (B) As shown in the schematic partial cross-sectional view of FIG. 32B, since the thickness of the light transmitting material layer 26 provided in the semi-shielded region 12 is different from a predetermined thickness, the semi-shielded region is formed. A defect region 14 in which the phase of light passing through 12 differs from a predetermined value. (C) As shown in the schematic partial cross-sectional view of FIG. 32C, the light passing through the semi-light-shielding region 12 because the semi-light-shielding layer 22 is missing or has a thickness different from a predetermined thickness. Defect area 14 whose amplitude transmittance is different from a predetermined value.

The defect (A) is, for example, the light transmitting material layer 26.
It can be corrected by forming a light-transmitting material having the same refractive index as that in the portion where the light-transmitting material layer is missing. Specifically, for example, by scanning the defect area with a focused ion beam in a silicon-containing gas atmosphere,
Silicon oxide is selectively deposited in the defect region, and thereby a light-transmitting material is formed in the defect region (such a repair method is hereinafter also referred to as a repair method by silicon oxide formation by FIB). Alternatively, the defect area is corrected by the so-called lift-off method. That is, after the resist is applied to the entire surface of the mask, the defective area is selectively exposed to light, or the resist is exposed by an electron beam, a focused ion beam, a laser beam, or the like, and then the resist is developed to expose the defective area. Selectively expose. afterwards,
This is a correction method in which a light-transmitting substance such as silicon oxide is applied to selectively form the light-transmitting substance only in the exposed defect region.

The defect (B) can be corrected by removing the thick portion of the light transmitting material layer. For example, a method of removing a thick portion of the light transmitting material layer by physical etching using a focused ion beam or the like is usually used.

Further, both the defects (A) and (B) or the defect (C) can be repaired by covering the defective region with a light shield. In this method, the focused ion beam is scanned in the defect-containing region in the carbon-containing gas atmosphere that has already been used in the conventional mask repair, and the carbon layer is selectively deposited in the defect region. Form.

[0012]

However, the defect correction of the conventional halftone type phase shift mask has the following problems.

When the defect of (A) is repaired by the repair method by forming silicon oxide by FIB, it is very difficult to maintain the concentration of the silicon-containing gas in the vicinity of the defect region constant and uniform. Furthermore, it is impossible to completely eliminate the influence of the gas remaining in the focused ion beam device. As a result, it is extremely difficult to form a light transmissive material having a desired thickness, shape, transmittance and refractive index in the defect area.

When the defect (A) is to be repaired by the lift-off method, the resist needs to be coated again on the entire surface of the halftone type phase shift mask. New defects occur in the tone phase shift mask. Further, after forming the light transmitting substance, it is necessary to perform ultrasonic peeling or the like to remove the resist and the applied light transmitting substance. However, at the time of ultrasonic peeling, not only the resist and the light-transmitting substance but also a part of the semi-light-shielding layer is peeled off, which causes a new defect. Further, in order to correct these newly generated defects, it is necessary to repeat the correction by a similar correction method, and it is not realistic to use the lift-off method as the defect correction method.

In the correction method of physically removing the defects of (B) by the focused ion beam, there is no great difference between the etching rate of the defect area and the etching rate of the normal light transmitting material layer. Therefore, unless the scanning position or the number of times of scanning of the focused ion beam is controlled extremely strictly, the light transmission material layer around the defect region or below the defect region is damaged. However, the location of the defective area that actually occurs is
The shape, thickness, etc. are not constant, and it is extremely difficult to precisely remove and correct only the defective area by the focused ion beam. Furthermore, the ions remain in the scanned portion during the ion beam scanning, and the amplitude transmittance decreases. It is impossible to remove the residual ions in the fine pattern, and this correction method is not realistic either.

The method of selectively covering the defect area with the light shield is a simple and easy method. Such a repairing method is described in, for example, the document “Study on Defect Repairing Method for Halftone Phase Shift Mask”, Proceedings No. 2,31p-L-15,
It is described on page 611. This document describes covering the defective area with a light-shielding film having the same size as the defective area and a transmittance of approximately 0.

However, when the pattern shape is transferred to the resist material formed on the wafer using the halftone phase shift mask in which the defect area is covered with a light shield having the same size as the defect area, the pattern as designed is obtained. There is a problem that the shape is not accurately transferred to the resist material. In particular, when the area of the light shield becomes large, the transferred pattern shape to the resist material obtained by the modified halftone phase shift mask is transferred to the resist material obtained by the halftone phase shift mask when there is no defect. It is significantly different from the pattern shape. Hereinafter, such a difference may be referred to as a “difference between the transfer pattern shape after the mask correction and the desired shape”.

For example, in a contact hole pattern formed on a halftone phase shift mask, one side of a semi-light-shielding region adjacent to the contact hole pattern is covered with a light shield. The light transmitting region is not covered with the light shield. In such a case, compared with the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect, the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask Is greater than 15%. The contact hole formed from such a transfer pattern shape significantly deteriorates the performance of the semiconductor device, and makes it extremely difficult to manufacture the semiconductor device itself.

In the conventional method of selectively covering the defective area with the light shield, when the defective area is small,
The area of the light shield can be reduced, and as a result, it may be possible to allow the difference in the transfer pattern shape after the mask correction from the desired shape. However, if the area of the light shield is reduced, it is difficult to secure sufficient correction accuracy when forming the light shield by the focused ion beam.

Factors that impair the correction accuracy are beam deviation from the desired light shield formation region due to drift of the focused ion beam, uneven concentration of the carbon-containing gas near the region irradiated with the focused ion beam, and focused ion beam The formation of the light shield in a region different from the desired light shield formation scheduled region due to drift or current fluctuation, and the occurrence of a human error in setting the light shield formation scheduled region can be mentioned. When the area of the light shield is made small, it is very difficult to avoid these factors that impair the correction accuracy. Therefore, uncorrected defects often occur, and there is a problem that the defects cannot be reliably corrected. In addition, it is extremely difficult to form a light shield having the same size as the defect area in reality.

A method for correcting defects in a shifter composed of a film transparent to exposure light is disclosed in, for example, Japanese Patent Laid-Open No. 4-165.
It is known from the publication No. 353. This publication discloses a method of correcting a shifter chip defect having a size that can be independently resolved by providing a light shielding part on the chip defect region so as to extend outside the shifter by a predetermined area. There is.

The phase shift mask described in this publication is not a halftone type phase shift mask but a so-called shifter shading type phase shift mask. Further, although the light shielding portion is made of a chrome film using the photo-CVD method, there is a problem that defects are generated again when the light shielding portion is formed. Furthermore, as is clear from FIGS. 6, 7, and 8 attached to this publication, inside the shifter, the defect defect area is covered with a light shield having the same size as the defect defect area of the shifter. Has been done. That is, there is no description or suggestion of covering a region larger than the chipped defect region with a light shield inside the shifter. In reality, it is extremely difficult to form a light-shielding body having the same size as the defective defect region of the shifter.

Therefore, the first object of the present invention is that the defective area is selectively and surely covered with the light-shielding body, and the difference of the transfer pattern shape after the mask correction from the desired shape does not pose a practical problem. An object of the present invention is to provide a halftone type phase shift mask in which a defective area is corrected.

The second object of the present invention is, selectively,
It is an object of the present invention to provide a halftone type phase shift mask repairing method capable of surely repairing a defective area by covering the defective area with a light shield with a sufficient repair margin and by an easy method.

A third object of the present invention is to provide a method of manufacturing a semiconductor device using such a halftone type phase shift mask.

[0026]

A first object of the present invention is to provide a half-shielded region and a light-transmitting region, wherein the phase of light passing through the semi-shielding region and the phase of light passing through the light-transmitting region are different from each other. A tone type phase shift mask, in which the phase, the amplitude transmittance, or both of them are different from predetermined values,
A repair region in a defect region larger than the defect region, which includes a defect region existing in a semi-shielded region adjacent to or close to the light transmission region, and a part of the light transmission region adjacent to or adjacent to the repair region are formed of a resist material. This can be achieved by the halftone phase shift mask of the present invention, which is characterized in that it is covered with a light shield having an amplitude transmittance that does not expose it to light.

In the halftone phase shift mask of the present invention, the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask is obtained by the halftone phase shift mask when there is no defective area. The position and shape of a part of the light transmission area adjacent to or close to the correction area, and the amplitude transmittance of the light shield may be selected as necessary so as to substantially match the shape of the transfer pattern to the resist material. desirable. In this case, the light shield is preferably made of carbon.

Alternatively, in the halftone phase shift mask of the present invention, the repair area is covered with a first light shield having an amplitude transmittance that does not expose the resist material to light, and the light transmission area adjacent to or adjacent to the repair area is transmitted. It is desirable that a part of the region is covered with a second light shield having an amplitude transmittance different from that of the first light shield. In this case, the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask is substantially the same as the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect region. As described above, it is preferable to select the position and shape of a part of the light transmission region adjacent to or close to the correction region, and further, the amplitude transmittance of the second light shield as necessary. Further, the first or second light shield is preferably made of carbon.

In the halftone phase shift mask of the present invention, the semi-light-shielding region is composed of at least the semi-light-shielding layer, and in this case, the defect region is composed of at least the lack of the semi-light-shielding layer, or at least the thickness of the semi-light-shielding layer. May differ from the predetermined value. It should be noted that the semi-shielded region preferably has an amplitude transmittance that is greater than 0 and does not resolve the resist material, more specifically, an amplitude transmittance that is greater than 0 and less than 0.55.

A second object of the present invention is to provide a halftone phase shift mask having a semi-shielded region and a light transmitting region, wherein the phase of light passing through the semi-shielding region and the phase of light passing through the light transmitting region are different. In, in the case where a defect region in which the phase, the amplitude transmittance, or both of them are different from a predetermined value exists in the semi-shielded region adjacent to or close to the light transmission region, the defect region is included in the semi-shielded region, and A book characterized in that a repair area larger than the defect area is selected, and the repair area and a part of the light transmitting area adjacent to or close to the repair area are covered with a light shield having an amplitude transmittance that does not expose the resist material to light. This can be achieved by the halftone phase shift mask correcting method according to the first aspect of the invention.

In the halftone phase shift mask repairing method according to the first aspect of the present invention, when the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask has no defective region. The position and shape of a part of the light transmission area adjacent to or close to the correction area, and if necessary, of the light shield so as to substantially match the transfer pattern shape to the resist material obtained by the halftone phase shift mask of It is desirable to choose the amplitude transmittance. In this case, the light shield is preferably made of carbon.

Alternatively, in the halftone phase shift mask repairing method according to the first aspect of the present invention, the repaired area is covered with a first light shield having an amplitude transmittance that does not expose the resist material to light and repairs it. It is preferable that a part of the light transmission region adjacent to or close to the region is covered with a second light shield having an amplitude transmittance different from that of the first light shield. Further, the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask should be substantially the same as the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect area. In addition, it is preferable to select the position and shape of a part of the light transmission region adjacent to or close to the correction region, and further to select the amplitude transmittance of the second light shield as necessary. Furthermore, the first or second light shield is preferably made of carbon.

In the method of repairing a halftone phase shift mask according to the first aspect of the present invention, the semi-light-shielding region is composed of at least the semi-light-shielding layer, and in this case, the defect region is at least due to the lack of the semi-light-shielding layer. In some cases, or at least the thickness of the semi-light-shielding layer is different from the predetermined value. It should be noted that the semi-shielded region preferably has an amplitude transmittance that is greater than 0 and does not resolve the resist material, more specifically, an amplitude transmittance that is greater than 0 and less than 0.55.

A second object of the present invention is to provide a half-tone phase having a semi-shielded region and a light-transmitting region, wherein the phase of light passing through the semi-shielding region and the phase of light passing through the light-transmitting region are different. In the shift mask, phase, amplitude transmittance,
Alternatively, when a defect area where both of them are different from the predetermined value exists in the semi-shielded area adjacent to or close to the light transmission area, the repair area including the defect area and larger than the defect area is selected in the semi-shielded area. A correction method for a halftone phase shift mask, in which a correction region and a part of a light transmission region adjacent to or close to the correction region are covered with a light shield having an amplitude transmittance that does not expose the resist material to light, The transfer pattern shape to the resist material obtained by the modified halftone phase shift mask based on the corrected area is a transfer pattern to the resist material obtained by the halftone phase shift mask when there is no defect area. The position and the position of a part of the light transmission region adjacent to or close to the correction region so as to substantially match the shape and Jo, can be accomplished by modifying the method of half-tone type phase shift mask according to a second aspect of the present invention and obtaining the further simulation or calculate the amplitude transmittance of the light blocking members as required.

In the modification method of the halftone phase shift mask according to the second aspect, it is preferable that the light shield is made of carbon.

The correction area is covered with a first light shield having an amplitude transmittance that does not expose the resist material to light, and a part of the light transmission area adjacent to or close to the correction area is provided in the first light shield. The transfer pattern shape to the resist material, which is covered with the second light shield having the amplitude transmittance different from the amplitude transmittance and is obtained by the modified halftone phase shift mask based on the selected correction area, The position and shape of a part of the light-transmitting area adjacent to or close to the correction area, and if necessary, so as to substantially match the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defective area. Accordingly, it is desirable to obtain the amplitude transmittance of the second light shield by simulation or calculation. In this case, the first or second light shield is preferably made of carbon.

Furthermore, in the halftone phase shift mask repairing method according to the second aspect, the semi-light-shielding region is composed of at least the semi-light-shielding layer, and in this case, the defect region is at least due to the lack of the semi-light-shielding layer. In some cases, or at least the thickness of the semi-light-shielding layer is different from the predetermined value. It should be noted that the semi-shielded region preferably has an amplitude transmittance that is greater than 0 and does not resolve the resist material, more specifically, an amplitude transmittance that is greater than 0 and less than 0.55.

A third object of the present invention is to form a halftone phase shift mask by exposing a resist material formed on a wafer using the above halftone phase shift mask of the present invention. This can be achieved by a method for manufacturing a semiconductor device, which is characterized in that the formed pattern shape is transferred to a resist material.

[0039]

In the present invention, since the repair area larger than the defect area is covered with the light shield, the defect area can be repaired with a high repair margin, that is, even if the repair accuracy is not very high. It is possible to prevent transfer of the defective area to the resist material and reduction of the depth of focus due to exposure.

Further, since a part of the light transmitting area adjacent to or close to the correction area is covered with the light shield, the change of the transfer pattern shape from the desired pattern shape which occurs when only the correction area is covered with the light shield. Misalignment can be corrected. Moreover, the width or position of the light shield or the transmittance,
Further, by precisely controlling all of these, it is possible to obtain a desired transfer pattern shape and a sufficient depth of focus accurately.

Further, by appropriately obtaining the position and size of the light shield suitable for the correction area by simulation, calculation or experiment, and accurately controlling the position and size of the light shield. The desired transfer pattern shape can be obtained efficiently and accurately.

[0042]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings based on embodiments. The relationship between each embodiment and the defect form is summarized as follows. Example-1 and Example-2: Correction of a defect area in which the amplitude transmittance and phase of the semi-shielded area are different from predetermined values. Example-4 and Example-5: Correction of a defective area in which the amplitude transmittance of the semi-shielded area is different from a predetermined value. Example-6: Correction of a defective area in which the phase of the semi-shielded area is different from a predetermined value. In these examples, the method of repairing the defective area is based on the method of repairing the halftone phase shift mask according to the first aspect of the present invention.

Example 3 relates to a halftone phase shift mask correcting method according to the second aspect of the present invention, wherein a method for selecting a correcting area and determining a part of a light transmitting area adjacent to the correcting area. An example of the method will be described.

When a transfer pattern shape or the like is formed on a resist material formed on a wafer by exposure light, one used for reduction projection is called a reticle, and one used for one-to-one projection is called a mask. In some cases, a reticle equivalent to the master disc may be referred to as a reticle, and a duplicate thereof may be referred to as a mask. In this specification, a reticle and a mask having various meanings as described above are collectively referred to as a mask. .

(Example-1) In Example-1, the defect region exists in the semi-shielded region adjacent to the light transmission region.
This defective region has a different phase and amplitude transmittance compared to the semi-shielded region having no defect. The repair area and a part of the light transmitting area adjacent to the repair area are covered with a light shield having an amplitude transmittance that does not expose the resist material to light. The correction area is located within the semi-shielded area. The light shield is made of carbon and has an amplitude transmittance of almost 0%. Hereinafter, Example-1 will be described with reference to FIGS.

As shown in the schematic partial plan view of FIG. 1A, the halftone phase shift mask 1 has a square light transmission region 1 which is a contact hole pattern.
0 and a semi-shielded area 12 are formed. The semi-shielded region 12 is shaded. Further, the defect region 14 exists adjacent to one side XY of the square light transmitting region 10. 1B and 1C are schematic partial cutaway views of the halftone phase shift mask taken along the lines BB and CC in FIG. 1. In the figure, 20 is a substrate made of, for example, quartz, and 22 is chromium (C
r) is a semi-light-shielding layer. The light transmission region 10 is a recess formed in the substrate by etching the semi-shielded region 12 and the substrate 20. The depth d of such a recess is
When the wavelength of the exposure light is λ and the refractive index of the substrate is n, d =
It is a value that satisfies λ / (2 (n-1)). That is, the phase of light passing through the semi-shielded region 12 and the phase of light passing through the light transmitting region 10 are made different by the portion 10B of the substrate from the surface to the depth d.

The size of the square light-transmitting region 10 was set to 1.85 μm × 1.85 μm on a 5 × reticle. Further, the amplitude transmittance of the semi-shielded region 12 was set to about 40%, and the phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 was set to 180 °.

The size of the defect area 14 was set to 1.0 μm × 1.0 μm on the 5 × reticle. In addition, the defect area 1
The amplitude transmittance of No. 4 was 100%, and the phase difference between the light passing through the defect region 14 and the light passing through the light transmitting region 10 was 0 °. The amplitude transmittance of 100% means that the light transmittance has the same amplitude transmittance as that of the light transmitting region 10. In Example-1, the defect region 14 shown by the broken line in FIG.
Is a defect in which the semi-light-shielding layer 22 and a part of the substrate 10B are missing, and has a different phase and amplitude transmittance as compared with a semi-light-shielding region having no defect. Such a defective area 14
Is likely to occur when the semi-shielded region 12 and the substrate 20 are etched to form the light transmission region 10.

Using the halftone phase shift mask 1 having such a defect region 14, a wavelength of 248n
m, NA 0.45, partial coherency 0.
When reduced exposure is performed to 1/5 with the exposure device of No. 3, the light intensity distribution of the light transmitted through the halftone phase shift mask 1 is as shown in FIG.
The light intensity distribution shown by the solid line (A) in (A). Further, the light intensity distribution of the light transmitted through the halftone phase shift mask without the defect region 14 is the same as the light intensity distribution shown by the dotted line (B) in FIG. 3A on the resist material formed on the wafer. became. In each of the following examples, the light intensity distribution on the resist material formed on the wafer was obtained under the same exposure apparatus and exposure conditions.

When the width of the light intensity distribution curve when the light intensity is 0.3 is defined as the contact hole pattern width, the contact hole pattern width obtained from the halftone phase shift mask in which the defect region 14 exists is 0. 4 μm, the contact hole pattern width 0.3 obtained from the halftone phase shift mask without the defect region 14.
It was increased by 0.1 μm as compared with μm. Further, the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect area 14 exists is the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect area 14 does not exist. 0.06 μm from center
It was off.

The modified halftone phase shift mask 1A is shown in FIG. As shown in the schematic partial plan view of (A) of FIG. 2 and the schematic partial cutaway views of (B) and (C) of FIG. 2, correction including a defect region 14 and larger than the defect region is performed. Region 16 (hatched in FIG. 2) is covered with a light shield 30 having an amplitude transmittance that does not expose the resist material to light. The correction area 16 is located in the semi-shielded area 12. Further, a part of the light transmission region 10A adjacent to the correction region 16 is covered with the same light shield 30.
The light shield 30 is made of carbon and has an amplitude transmittance of almost 0%. 2B and 2C are sectional views taken along lines BB and CC of FIG. 2A.

By forming such a light shield 30, the light intensity distribution shown in FIG. 3B is obtained. In this case, the contact hole pattern width becomes 0.301 μm, and the desired contact hole pattern width ( 0.3 μm)
Well matched. In addition, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 was less than 0.01 μm.

A specific method for correcting the defective area 14 shown in FIG. 1 will be described below with reference to FIG. In the halftone phase shift mask 1 having the defect region 14, a repair region 16 (shown by a broken line in FIG. 4) including the defect region 14 and larger than the defect region 14 is selected in the semi-shielded region 12. The size of the correction area 16 is 2.0
The size was set to μm × 1.8 μm. The size of the defect area 14 is 1.0 μm × 1.0 μm, and the repair area 16 includes the defect area 14 and is larger than the defect area 14.

The correction area 16 thus selected and a part 10A of the light transmission area adjacent to the correction area 16 (see FIG. 4).
(Indicated by the dotted line), the acceleration voltage is 20K in a pyrene gas atmosphere controlled to a pressure of 1.3 × 10 ⁻⁴ Pa or less.
By scanning a Ga ⁺ focused ion beam of V and an ion current of 120 pA for 2 minutes, a light shield 30 made of carbon and having a thickness of 300 nm was formed. The part 10A of the light transmitting area adjacent to the correction area 16 is one side X of the light transmitting area 10.
It extends from Y by 0.2 μm toward the center of the light transmitting region. That is, the overall size of the light shield 30 is 2.0 μ.
m × 2.0 μm. Thus, the halftone type phase shift mask 1A in which the defect area 14 was corrected could be obtained. A method for selecting the correction area 16 and a method for determining the size of the portion 10A of the light transmission area adjacent to the correction area 16 will be specifically described in Example-3.

Defect area 14 (for example, 1.0 μm × 1.
Correction area 16 (eg, 2.0 μm) larger than 0 μm
× 1.8 μm) is selected, and the light shield 30 is formed on the correction region 16. As a result, a high correction margin can be obtained.

Further, the light shield 30 is also formed on the part 10A (for example, 2.0 μm × 0.2 μm) of the light transmission region adjacent to the correction region 16. As a result, the light intensity distribution approaches the desired distribution, and the desired contact hole pattern width is obtained. In fact, an embodiment modified in this way-
Using the halftone phase shift mask 1A of 1,
When the pattern shape formed on the halftone type phase shift mask 1A was transferred to the resist material formed on the wafer and the contact hole pattern width was measured using an electron beam dimension measuring device, a desired contact hole pattern width was found. It was confirmed that it was obtained. It was also confirmed that the contact hole pattern width was in agreement with the contact hole pattern width obtained from the light intensity distribution.

When the light shield 30 is formed on the correction area 16 and the light transmission area 10 adjacent to the correction area 16 is not formed, the light intensity of the light passing through the halftone phase shift mask. The distribution was a curve shown by the alternate long and short dash line (C) in FIG.

(Modification of Embodiment-1) FIG. 5 is a schematic partial cutaway view of a halftone phase shift mask having a structure different from that shown in FIG. In addition, these sectional views are sectional views taken along the line C-C in FIG. The defect region 14 shown by the broken line has a different phase and amplitude transmittance as compared with the semi-shielded region having no defect.

The halftone phase shift mask shown in FIG. 5A comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. The semi-light-shielding region 12 is composed of a semi-light-shielding layer 22 made of chromium, and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG (spin on glass) formed thereon. The light that has passed through the light transmission region 10 and the semi-shielded region 12
The phase difference with the light passing through is 180 °, for example. The thickness d of the light transmissive material layer 26 is d = λ / (2 (n−) where λ is the wavelength of the exposure light and n is the refractive index of the light transmissive material layer.
The value satisfies 1)). The defect region 14 shown by a broken line in FIG.
It is a defect in which a part of is missing. Such a defect area 14 is likely to occur when the light-transmitting area 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed on the substrate 20.

A schematic partial cutaway view of a halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 5A in the same manner as in Example 1 is shown in FIG. B).

The halftone phase shift mask shown in FIG. 5C comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. The semi-light-shielding region 12 is composed of a semi-light-shielding layer 22 made of chromium and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed between the semi-light-shielding layer 22 and the substrate 20. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. The thickness d of the light transmitting material layer 26 is d = λ / (2 (n-1)), where λ is the wavelength of the exposure light and n is the refractive index of the light transmitting material layer.
Is a value that satisfies The defect area 14 is a defect in which a part of the semi-light-shielding layer 22 and the light transmitting material layer 26 is missing. Such a defect area 14 is likely to occur when the light-transmitting area 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed on the substrate 20.

A schematic partial cutaway view of the halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 5C by the same method as in Example-1 is shown in FIG. It is shown in D).

Example-2 Example-2 is the same as Example-1.
Is a variation of. The structure of the halftone phase shift mask and the form of the defect area in the second embodiment are the same as those in the first embodiment.
Is the same as. The example 2 differs from the example 1 in the method of correcting the defective area. That is, the correction area is covered with the first light shield having an amplitude transmittance that does not expose the resist material to light. Further, a part of the light transmission area adjacent to the correction area is covered with a second light shield having an amplitude transmittance different from that of the first light shield.

In a contact hole pattern (see FIG. 1) having a defect region similar to the defect region 14 shown in Example-1, as shown in the schematic partial plan view and partial cutaway view of FIG. The correction area 16 is covered with a first light shield 32 having an amplitude transmittance that does not expose the resist material to light. In addition, a portion 10A of the light transmission area adjacent to the correction area
Is covered with a second light shield 34 having an amplitude transmittance different from that of the first light shield. The first light shield 32 is made of carbon and has an amplitude transmittance of about 0%.
The second light shield 34 is also made of carbon and has an amplitude transmittance of about 20%. First light shield 32 and second light shield 34
The amplitude transmittance is changed by varying the thickness of the.

By accurately controlling the positions, widths, thicknesses, etc. of the first and second light shields 32, 34 to be formed, FIG.
The light intensity distribution shown in was obtained. In this case, the contact hole pattern width was 0.301 μm, which was in good agreement with the desired contact hole pattern width (0.3 μm).
Further, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 is 0.01 μm.
It was less than m.

The defect area 14 in Example-2 can be repaired by the following method. The structure of the halftone phase shift mask, the defect region, and the size and form are shown in FIG.
Is the same as. The size of the correction area 16 is 1.85 μm ×
The size was 1.85 μm. The size of the defect area 14 is 1.0 μm × 1.0 μm, and the repair area 16 includes the defect area 14 and is larger than the defect area 14. Correction area 1
6 is located in the semi-shielded area 12.

With respect to the correction region 16 thus selected, an accelerating voltage of 20 KV and an ion current of 120 pA in a pyrene gas atmosphere controlled to a pressure of 1.3 × 10 ^-4 Pa or less.
The first light shield 32 made of carbon and having a thickness of 300 nm was formed by scanning with a Ga ⁺ focused ion beam of 2 minutes.

Further, by scanning the part 10A of the light transmitting region adjacent to the correction region 16 with the Ga ⁺ focused ion beam, a thickness of 150 n having an amplitude transmittance of about 20% is obtained.
A second light shield 34 made of m of carbon was formed. A part 10A of the light transmitting region extends 0.7 μm from one side XY of the light transmitting region 10 toward the center of the light transmitting region. In this way, the halftone phase shift mask 1B in which the defect area 14 is corrected can be obtained. still,
A method for selecting the correction area 16 and a method for determining the size of the portion 10A of the light transmission area adjacent to the correction area 16 will be specifically described in Example-3.

The first light shield 32 is also formed on a part of the semi-light-shielding region 12 having no defect other than the defect region 14 in order to obtain the correction margin, but a part of the light-transmitting region 10A is covered. By controlling the amplitude transmittance and the width of the second light shield 34, the light intensity distribution approaches the desired transfer pattern shape, and the desired contact hole pattern width is obtained.

(Modification of Example-2) FIG. 8 is a schematic partial cutaway view of a halftone phase shift mask having a structure different from that shown in FIG. In addition, these sectional views are sectional views taken along the line C-C in FIG. The defect region 14 shown by the broken line has a different phase and amplitude transmittance as compared with the semi-shielded region having no defect.

The halftone phase shift mask shown in FIG. 8A has the same structure and defect region 1 as the halftone phase shift mask described in FIG. 5A.
Have 4. 8B is a schematic partial cutaway view of a halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 8A by the same method as in Example-2. Show.

The halftone type phase shift mask shown in FIG. 8C has the same structure and defect region 1 as the halftone type phase shift mask described in FIG. 5C.
Have 4. 8D is a schematic partial cutaway view of a halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 8C by the same method as in Example-2. Show.

(Embodiment 3) Embodiment 3 relates to a halftone phase shift mask correcting method according to the second aspect of the present invention. In Example-3, an example of a method of selecting a correction area and a method of selecting a part 10A of the light transmission area adjacent to the correction area 16 will be described. The structure of the halftone phase shift mask in Example-3 and the form, shape, and size of the defect region are the same as in Example-1. The pattern of the light transmitting area 10 will be described as a line pattern.

120 pA Ga ⁺ accelerated at 20 KV
The focused ion beam scans the halftone phase shift mask 1 having the defect region 14 shown in FIG. A two-dimensional distribution of the secondary ions or secondary ion intensity of Cr generated by this is measured, and this is stored in the memory of the scanning device, and a two-dimensional image is displayed on a display device such as a character display (hereinafter abbreviated as CRT). Display as.

Next, referring to this display, as shown in FIG. 9A, an appropriate area AB including the defect area 14 is formed.
Specify the CD. A part of this area ABCD is the correction area 1
Equivalent to 6. Here, AB = CD = 2.0 μm, B
C = DA = 2.5 μm, but it is not limited to this value.

The boundary between the light transmitting region 10 and the semi-shielded region 12 is detected by detecting the point where the secondary ion intensity changes remarkably on each side of ABCD by image processing.
Further, the intersection EF between this boundary and the side of the area ABCD is detected. In FIG. 9A, the intersection E on the side BC is
An example in which the intersection F is detected on the side AD is shown.

Next, the transfer pattern shape to the resist material obtained by the modified halftone phase shift mask is the same as the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect area. The length (EG and FH) of a portion 10A of the light transmission region adjacent to the correction region 16 that should extend from one side XY of the light transmission region 10 toward the central portion of the light transmission region so as to substantially match, And, if necessary, the amplitude transmittance of the light shield is obtained. For that, AF, AB, BE, E
Based on the length of F, EG and F can be simulated or calculated from data based on the light intensity distribution previously obtained by simulation or calculation or experiment.
The position and shape of the portion 10A of the light transmission region adjacent to the correction region 16 such as the length of H and the like, and the amplitude transmittance of the light shield as necessary are obtained. In Example-3, EG = FH =
0.2 μm was obtained (see FIG. 9B).

In the formation of the correction region 16 and the part 10A of the light transmission region by the focused ion beam, the area of these regions formed is generally larger than the scanning range of the focused ion beam. Therefore, the focused ion beam scanning region IJKL (see FIG. 9B) for forming the region ABGH is calculated in advance by data obtained by simulation or calculation or experiment.

In this way, the position and shape of the part 10A of the light transmission area adjacent to the correction area 16 and the amplitude transmittance of the light shield are selected as required. Then, in the same manner as in Example-1, the correction area 16 and a part 10A of the light transmission area adjacent to the correction area 16 are covered with the light shield 30 having an amplitude transmittance that does not expose the resist material to light.

Alternatively, based on the lengths of AF, AB, BE, and EF, the lengths of EG and FH are corrected by simulation or calculation from data based on the light intensity distribution previously obtained by simulation or calculation or experiment. Part of the light transmitting area 10A adjacent to the area 16
Position and shape, and if necessary, the amplitude transmittance of the second light shield 34. Then, in the same manner as in Example-2, the repair area 16 is covered with the first light shield 32, and the part 10A of the light transmission area adjacent to the repair area 16 is covered with the second light shield 34.

As a result, in the modified halftone phase shift mask, it is possible to obtain a good transfer pattern in which the fluctuation of the transfer pattern line width to the resist material is suppressed to 5% or less with respect to the desired line width. did it.

Incidentally, in order to observe and repair the defect area 14, C
Although the secondary ion of r is used, the image data acquisition means is not limited to this, and if the image data can be acquired, a secondary ion of an element or molecule other than Cr or a secondary electron may be used. Good.

In the third embodiment, the correction of the defect area 14 generated in the isolated line has been described as an example. However, the invention is not limited to the isolated line, and it is extremely easy to apply the method to all the various device patterns. 3 can be applied. Further, the defect area 14 does not necessarily have to be adjacent to the pattern, and may be near the pattern. Further, the area ABCD may be set depending on the size or shape of the defect area 14, which is extremely versatile.
An optical microscope or a scanning electron microscope may be used as a means for obtaining the two-dimensional image shape of the halftone phase shift mask.

The correction method of the halftone phase shift mask according to the second aspect of the present invention described in the embodiment 3 is not limited to the embodiment 1 and the embodiment 2, but the embodiment described below. -4 to Example-6 can also be applied.

Example-4 Example-4 is the same as Example-1.
Is a variation of. Example-4 is different from Example-1 in that
The difference is in the form of defects in the defect region 14. That is, the defect region 14 has a different amplitude transmittance as compared with the semi-shielded region having no defect. The method of repairing the defective area 14 is the same as in Example-1. Hereinafter, the defect area 14 will be mainly described with reference to FIGS. 10 to 13.

As shown in the schematic partial plan view of FIG. 10A, the halftone phase shift mask 1 includes
Square light transmission area 1 which is a contact hole pattern
0 and a semi-shielded area 12 are formed. The semi-shielded region 12 is shaded. Further, the defect region 14 exists adjacent to one side XY of the square light transmitting region 10. A schematic partial cutaway view of the halftone phase shift mask taken along line BB of FIG. 10 is shown in FIG. In the figure, 20 is a substrate made of, for example, quartz, and 22 is a semi-light-shielding layer made of chromium that constitutes the semi-light-shielding region 12. The light transmitting region 10 is a recess having a depth d formed in the substrate by etching the substrate 20.

The size of the square light transmitting region 10 was set to 1.85 μm × 1.85 μm on the 5 × reticle. Further, the amplitude transmittance of the semi-shielded region 12 was set to about 40%, and the phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 was set to 180 °.

The size of the defect area 14 was set to 1.85 μm × 1.85 μm on the 5 × reticle. The amplitude transmittance of the defect area 14 was 100%, and the phase difference between the light passing through the defect area 14 and the light passing through the light transmitting area 10 was 180 °. In Example-4, the defect region 14 shown by the broken line in FIG. 10B is a defect in which a part of the semi-shielding layer 22 is missing, and has an amplitude larger than that of the defect-free semi-shielding region. The transmittance is different. Such defective area 14 is
It is likely to occur when the light-transmitting region 10 is formed by etching the semi-shielded region 12 and the substrate 20.

Using a halftone phase shift mask having such a defect region 14, a wavelength of 248 nm,
When an exposure apparatus having an NA of 0.45 and a partial coherency of 0.3 is used to perform reduction exposure to ⅕, the light intensity distribution of the light transmitted through the halftone phase shift mask 1 is on the resist material formed on the wafer. In, the light intensity distribution shown in FIG. 12 was obtained. Two peaks, a peak P1 due to the light passing through the light transmitting region 10 and a peak P2 due to the light passing through the defect region 14, were recognized in the light intensity distribution.

When the width of the light intensity distribution curve when the light intensity is 0.3 is defined as the contact hole pattern width, the contact hole pattern width obtained from the halftone phase shift mask in which the defect region 14 exists is 0.27 μm.
And the contact hole pattern width 0..0 obtained from the halftone phase shift mask without the defect region 14.
It was decreased by 0.03 μm as compared with 3 μm. Also,
The center of the peak P1 of the light intensity distribution curve obtained from the halftone phase shift mask 1 in which the defect region 14 exists is from the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect region 14 is not present. It was offset by 0.03 μm. Further, due to the peak P2, an unnecessary pattern was formed on the resist material formed on the wafer.

FIG. 11 shows the modified halftone phase shift mask 1A. As shown in the schematic partial plan view of (A) of FIG. 11 and the schematic partial cutaway view of (B) of FIG. 11, a correction region 16 including a defect region 14 and larger than the defect region (FIG. 11 is shaded) is covered with a light shield 30 having an amplitude transmittance that does not expose the resist material to light. Further, a part of the light transmission region 10A adjacent to the correction region 16 is covered with the same light shield 30.
The light shield 30 is made of carbon and has an amplitude transmittance of almost 0%. In addition, FIG. 11B is a line BB of FIG.
FIG. The size of the correction area 16 and the portion 10A of the light transmission area was the same as in Example-1.

By forming such a light shield 30, a light intensity distribution similar to that shown in FIG. 3B was obtained. In this case, the contact hole pattern width is 0.
It was 301 μm, which was in good agreement with the desired contact hole pattern width (0.3 μm). In addition, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 was less than 0.01 μm. Moreover, the presence of unnecessary peaks was not recognized.

The correction process in Example-4 is the same as in Example-1.
Since the process is the same as that of step 1, the details are omitted.

Actually, using the halftone phase shift mask of Example 4 thus modified, the pattern shape formed on the halftone phase shift mask was transferred to the resist material formed on the wafer, When the contact hole pattern width was measured using an electron beam dimension measuring device, it was confirmed that the desired contact hole pattern width was obtained. It was also confirmed that the contact hole pattern width was in agreement with the contact hole pattern width obtained from the light intensity distribution.

(Modification of Example-4 [Part 1]) Example-
The defect area 14 described in Section 4 can also be repaired by the repair method described in Example-2.

A contact hole pattern having a defect region similar to the defect region shown in Example 4 (see FIG. 10).
On the other hand, as shown in the schematic partial plan view and partial cutaway view of FIG. 13, the correction region 16 is covered with the first light shield 32 having an amplitude transmittance that does not expose the resist material to light.
In addition, a part 10A of the light transmission area adjacent to the correction area is
It is covered with a second light shield 34 having an amplitude transmittance different from that of the first light shield. Similar to Example-2, the first light shield 32 was made of carbon and had an amplitude transmittance of about 0%. The second light shield 34 is also made of carbon and has an amplitude transmittance of about 20%. The thicknesses of the first light shield 32 and the second light shield 34 are 300 nm and 15 respectively.
The amplitude transmittance is changed by setting it to 0 nm.

The defect area 14 can be repaired in the same manner as in Example 2, and detailed description thereof will be omitted. The size of the correction area 16 was set to 2.0 μm × 2.0 μm. Further, a part of the light transmitting area 10A is the light transmitting area 10A.
It extends from one side toward the center of the light transmitting region by 0.7 μm. In this way, the halftone phase shift mask 1B in which the defect area 14 is corrected can be obtained.

In order to obtain the correction margin, the first light shield 32 is also formed on a part of the semi-light-shielding region 12 having no defect other than the defect region 14, but the part 10A of the light transmitting region 10 is formed.
By controlling the amplitude transmittance, width, etc. of the second light shield 34 that covers the light shielding layer 34, the light intensity distribution approaches the desired transfer pattern shape, and the desired contact hole pattern width is obtained.

(Modification of Embodiment-4 [No. 2]) This modification of Embodiment-4 has a different structure from the halftone phase shift mask of Embodiment-4. A modification of this Example-4 is shown in schematic partial cutaway views in FIGS. 14 and 15.
In addition, these sectional views are sectional views taken along line BB in FIG. The defect region 14 has a different amplitude transmittance as compared to the semi-shielded region having no defect.

The halftone phase shift mask shown in FIG. 14 is similar to the halftone phase shift mask shown in FIG.
0 and a semi-shielded region 12 formed thereon.
The semi-light-shielding region 12 is composed of a semi-light-shielding layer 22 made of chromium and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed thereon. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. The defect region 14 shown in FIG. 14A is a defect in which a part of the semi-shielding layer 22 is missing. The defective area 14 is formed on the substrate 20.
It is likely to occur when the light-transmitting region 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed thereon.

A schematic partial cutaway view of a halftone type phase shift mask obtained by modifying the halftone type phase shift mask shown in FIG. 14A by the same method as in Example-1 is shown in FIG. B). 14C is a schematic partial cutaway view of a halftone phase shift mask modified by the same method as in Example-2.

The halftone phase shift mask shown in FIG. 15 comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. Semi-shielded area 12
Is composed of a semi-light-shielding layer 22 made of chromium and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed between the semi-light-shielding layer 22 and the substrate 20. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. Defective area 14
Is a defect in which a part of the semi-light-shielding layer 22 is missing. Such a defect area 14 is likely to occur when the light-transmitting area 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed on the substrate 20.

A schematic partial cutaway view of a halftone type phase shift mask obtained by modifying the halftone type phase shift mask shown in FIG. 15A by the same method as in Example-1 is shown in FIG. B). Further, a schematic partial cutaway view of a halftone phase shift mask modified by the same method as in Example-2 is shown in FIG.

Example-5 Example-5 is the same as Example-4.
Is a variation of. Example-5 differs from Example-4 in that
The difference is in the form of defects in the defect region 14. Specifically, the thickness of the semi-light-shielding layer 22 in the defect area 14 is thicker than other portions. The method of repairing the defective area 14 is the same as in Example-1. Hereinafter, the defect area 14 will be mainly described with reference to FIGS.

As shown in the schematic partial plan view of FIG. 16A, the halftone phase shift mask 1 includes
Square light transmission area 1 which is a contact hole pattern
0 and a semi-shielded area 12 are formed. The semi-shielded region 12 is shaded. Further, the defect region 14 exists adjacent to one side XY of the square light transmitting region 10. FIG. 16B is a schematic partial cutaway view of the halftone phase shift mask taken along lines BB and CC of FIG.
And (C). In the figure, 20 is a substrate made of, for example, quartz, and 22 is a semi-light-shielding layer made of chromium that constitutes the semi-light-shielding region 12. The light transmission region 10 is a recess having a depth d formed in the substrate.

The size of the square light transmitting region 10 was set to 1.85 μm × 1.85 μm on the 5 × reticle. The amplitude transmittance of the semi-shielded region 12 was set to about 40%, and the phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielding region 12 was set to 180 °.

The size of the defect area 14 was set to 1.0 μm × 1.0 μm on the 5 × reticle. In addition, the defect area 1
The amplitude transmittance of No. 4 was about 0%, and the phase difference between the light passing through the defect region 14 and the light passing through the light transmitting region 10 was 180 °. In Example-5, the defect region 14 shown by the broken line in FIG. 16C is a defect in which the semi-light-shielding layer 22 is thicker than other portions, and is compared with the defect-free semi-light-shielding region. Therefore, the amplitude transmittance is different. Such defective area 14 is
It is likely to occur due to variations in film forming conditions during film formation of the semi-shielding layer 22.

Using a halftone type phase shift mask having such a defect region 14, a wavelength of 248 nm,
When an exposure apparatus having an NA of 0.45 and a partial coherency of 0.3 is used to perform a reduction exposure to 1/5, the light intensity distribution of the light transmitted through the halftone phase shift mask is on the resist material formed on the wafer. The light intensity distribution shown in FIG.

If the width of the light intensity distribution curve when the light intensity is 0.3 is defined as the contact hole pattern width, the halftone phase shift mask 1 in which the defect region 14 exists.
The contact hole pattern width obtained from is 0.34μ
m, which was 0.04 μm larger than the contact hole pattern width of 0.3 μm obtained from the halftone phase shift mask having no defect region 14. The center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask having the defect area 14 is the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask having no defect area 14. It was offset by 0.02 μm.

The modified halftone phase shift mask 1A is shown in FIG. As shown in the schematic partial plan view of (A) of FIG. 17 and the schematic partial cutaway views of (B) and (C) of FIG. 17, correction including a defect region 14 and larger than the defect region is performed. Area 16 (hatched in Figure 17)
Is covered with a light shield 30 having an amplitude transmittance that does not expose the resist material to light. Further, a part of the light transmission region 10A adjacent to the correction region 16 is covered with the same light shield 30. The light shield 30 is made of carbon and has an amplitude transmittance of almost 0%. 17B and 17C are sectional views taken along the lines BB and CC of FIG. 17A. The size of the correction area 16 and the portion 10A of the light transmission area was the same as in Example-1.

By forming such a light shield 30, a light intensity distribution similar to that shown in FIG. 3B was obtained. In this case, the contact hole pattern width is 0.
It was 301 μm, which was in good agreement with the desired contact hole pattern width (0.3 μm). In addition, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 was less than 0.01 μm.

The correction process in Example-5 is the same as in Example-1.
Since the process is the same as that of step 1, the details are omitted.

(Modification of Example-5 [Part 1]) Example-
The defect area 14 described in No. 5 can be repaired by the repair method described in Embodiment-2.

Contact hole pattern having a defect region similar to the defect region shown in Example-5 (see FIG. 16).
On the other hand, as shown in the schematic partial plan view and partial cutaway view of FIG. 19, the correction region 16 is covered with the first light shield 32 having an amplitude transmittance that does not expose the resist material to light.
In addition, a part 10A of the light transmission area adjacent to the correction area is
It is covered with a second light shield 34 having an amplitude transmittance different from that of the first light shield. Similar to Example-2, the first light shield 32 was made of carbon and had an amplitude transmittance of about 0%. The second light shield 34 is also made of carbon and has an amplitude transmittance of about 20%. The thicknesses of the first light shield 32 and the second light shield 34 are 300 nm and 15 respectively.
The amplitude transmittance is changed by setting it to 0 nm.

The defect area 14 can be repaired in the same manner as in Example-2, and detailed description thereof will be omitted. The size of the correction area 16 was set to 2.0 μm × 2.0 μm. Further, a part of the light transmitting area 10A is the light transmitting area 10A.
It extends from one side toward the center of the light transmitting region by 0.7 μm. In this way, the halftone phase shift mask 1B in which the defect area 14 is corrected can be obtained.

The first light shield 32 is also formed on a part of the semi-light-shielding region 12 having no defect other than the defect region 14 in order to obtain the correction margin, but a part of the light-transmitting region 10A is covered. By controlling the amplitude transmittance and the width of the second light shield 34, the light intensity distribution approaches the desired transfer pattern shape, and the desired contact hole pattern width is obtained.

The fifth embodiment or its modification has been described with reference to an example in which the thickness of the semi-light-shielding layer 22 in the defect region 14 is thicker than other portions. The thickness of the semi-light-shielding layer 22 in the defect region 14 has been described. Even when is thinner than other portions, it can be corrected by the same method as in Example-5 or its modification.

(Modification of Example-5 [Part 2]) This modification of Example-5 has a different structure from the halftone phase shift mask of Example-5. A modification of this Example-5 is shown in FIGS.
Note that these sectional views are sectional views taken along the line C-C in FIG. The defect region 14 shown by the broken line has a different amplitude transmittance as compared with the semi-shielded region having no defect.

The halftone phase shift mask shown in FIG. 20 comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. Semi-shielded area 12
Is composed of a semi-light-shielding layer 22 made of chromium, and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed thereon. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. The defect region 14 shown by the broken line in FIG. 20A is a defect in which the semi-light-shielding layer 22 is partially thick and the amplitude transmittance is different. Such a defect area 14 is likely to occur when the semi-light-shielding layer 22 is formed on the substrate 20.

20A is a schematic partial sectional view of a halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 20A by the same method as in Example-1. B). 20C is a schematic partial cutaway view of a halftone phase shift mask modified by the same method as in Example-2.

The halftone phase shift mask shown in FIG. 21 comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. Semi-shielded area 12
Is composed of a semi-light-shielding layer 22 made of chromium and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed between the semi-light-shielding layer 22 and the substrate 20. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. FIG. 21 (A)
The defect region 14 indicated by the broken line is also a defect in which a part of the semi-shielding layer 22 is thick and the amplitude transmittance is different. Such a defect area 14 is likely to occur when the semi-light-shielding layer 22 is formed on the substrate 20.

A schematic partial cutaway view of a halftone type phase shift mask obtained by modifying the halftone type phase shift mask shown in FIG. 21A by the same method as in Example-1 is shown in FIG. B). Further, FIG. 21C shows a schematic partial cutaway view of the halftone phase shift mask modified by the same method as in Example-2.

(Embodiment 6) The defect in the halftone phase shift mask in the embodiment 6 is as follows.
The form is different from the defect (at least the defect of the semi-shielding layer 22 forming the semi-shielding region 12) in the halftone type phase shift mask described in the first embodiment, the second embodiment, the fourth embodiment and the fifth embodiment.

The semi-light-shielding region 12 in the halftone phase shift mask of Example 6 is composed of the semi-light-shielding layer 22 formed on the substrate 20 and the light-transmitting material layer 26 formed thereon, or The light-transmitting material layer 26 is formed on the surface 20 and the semi-light-shielding layer 22 is formed thereon. The form of the defect is a partial lack of the light transmitting material layer 26 or a difference in the thickness of the light transmitting material layer 26. That is, the defect region 14 has a different phase of light as compared with the defect-free semi-shielded region.

FIG. 22 is a schematic partial cutaway view of the halftone phase shift mask of Example-6. The sectional views of FIGS. 22B and 22C are sectional views taken along lines BB and CC of FIG. The defect region 14 shown by the broken line is
The phases are different.

The halftone phase shift mask shown in FIG. 22 comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. Semi-shielded area 12
Is composed of a semi-light-shielding layer 22 made of chromium, and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed thereon. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. The thickness d of the light transmitting material layer 26 is d, where λ is the wavelength of the exposure light and n is the refractive index of the light transmitting material layer.
= Λ / (2 (n-1)).

Defect area 1 shown by a broken line in FIG.
4 is a defect in which a part of the light transmitting material layer 26 is missing. Such a defect area 14 is likely to occur when the light-transmitting area 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed on the substrate 20.

The size of the square light transmitting region 10 was set to 1.85 μm × 1.85 μm on the 5 × reticle. The amplitude transmittance of the semi-shielded region 12 was set to about 40%, and the phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielding region 12 was set to 180 °.

The size of the defect region 14 was set to 1.0 μm × 1.0 μm on the 5 × reticle. In addition, the defect area 1
The amplitude transmittance of No. 4 was about 40%, and the phase difference between the light passing through the defect region 14 and the light passing through the light transmitting region 10 was 0 °.

Using the halftone type phase shift mask 1 having such a defect region 14, a wavelength of 248n
m, NA 0.45, partial coherency 0.
When the exposure device of No. 3 reduces the exposure to ⅕, the light intensity distribution of the light transmitted through the halftone phase shift mask 1 is as shown in FIG. 2 on the resist material formed on the wafer.
The light intensity distribution shown in FIG.

When the width of the light intensity distribution curve when the light intensity is 0.3 is defined as the contact hole pattern width, the contact hole pattern width obtained from the halftone type phase shift mask in which the defect region 14 exists is 0. 36 μm
And the contact hole pattern width of 0..0 obtained from the halftone phase shift mask without the defect region 14.
It was increased by 0.06 μm as compared with 3 μm. Also,
The center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect region 14 exists is the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect region 14 is absent. 0.03
It was offset by μm.

FIG. 23 shows a halftone phase shift mask 1A after correction by the same correction method as in Example-1. As shown in the schematic partial plan view of (A) of FIG. 23 and the schematic partial cutaway views of (B) and (C) of FIG.
Repair area 1 including the defect area 14 and larger than the defect area
6 (hatched in FIG. 23) is covered with a light shield 30 having an amplitude transmittance that does not expose the resist material to light. Further, a part 1 of the light transmission area adjacent to the correction area 16
0A is covered with the same light shield 30. Light shield 30
Is made of carbon and has an amplitude transmittance of almost 0%. 23 (B) and (C) are line BB of FIG. 23 (A).
And C-C is a cutaway view. The size of the correction area 16 and the portion 10A of the light transmission area was the same as in Example-1.

By forming such a light shield 30, a light intensity distribution similar to that shown in FIG. 3B can be obtained. In this case, the contact hole pattern width is 0.30.
It was 1 μm, which was in good agreement with the desired contact hole pattern width (0.3 μm). In addition, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 was less than 0.01 μm.

The defect area 14 in the sixth embodiment can be corrected in the same manner as in the first embodiment, and detailed description thereof will be omitted.

(Modification of Example 6 [No. 1]) The defect region 14 shown in FIG. 22 can be repaired by the same method as in Example-2. A schematic partial cutaway view of the halftone phase shift mask modified by the same method as in Example-2 is shown in FIG.

(Modification of Example-6 [Part 2]) FIGS. 24B and 24C are schematic views of a halftone phase shift mask modified by another modification of Example-6. A partial cutaway view is shown. The sectional views of FIGS. 24B and 24C are sectional views taken along the line C-C of FIG.
The defect region 14 has a different phase than the defect-free semi-shielded region. Specifically, the thickness of the light transmitting material layer 26 is different from that of other portions. Such a defect region 14 is likely to occur when the light transmitting material layer 26 is formed.

The sectional view of FIG. 24B is an example in which the defect area 14 is corrected based on the correction method of Example-1,
The sectional view of FIG. 24C is an example in which the defect area 14 is corrected based on the correction method of the example-2.

The size of the square light transmitting region 10 was set to 1.85 μm × 1.85 μm on the 5 × reticle. The amplitude transmittance of the semi-shielded region 12 was set to about 40%, and the phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielding region 12 was set to 180 °.

The size of the defect area 14 was set to 1.0 μm × 1.0 μm on the 5 × reticle. In addition, the defect area 1
The amplitude transmittance of No. 4 was about 40%, and the phase difference between the light passing through the defect region 14 and the light passing through the light transmitting region 10 was 90 °.

Using the halftone phase shift mask 1 having such a defect region 14, a wavelength of 248n
m, NA 0.45, partial coherency 0.
When the exposure device of No. 3 reduces the exposure to ⅕, the light intensity distribution of the light transmitted through the halftone phase shift mask 1 is as shown in FIG. 2 on the resist material formed on the wafer.
The light intensity distribution shown in FIG.

If the width of the light intensity distribution curve when the light intensity is 0.3 is defined as the contact hole pattern width, the contact hole pattern width obtained from the halftone phase shift mask in which the defect region 14 exists is 0. 34 μm
And the contact hole pattern width of 0..0 obtained from the halftone phase shift mask without the defect region 14.
It was increased by 0.04 μm as compared with 3 μm. Also,
The center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect region 14 exists is the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask in which the defect region 14 is absent. 0.02
It was offset by μm.

When the defect area 14 is repaired based on the repair method of Example-1 (see FIG. 24B), or when the defect area 14 is repaired based on the repair method of Example-2 ( A light intensity distribution similar to that shown in FIG. 24C) and FIG. 3B is obtained. In this case, the contact hole pattern width is 0.301 μm, and the desired contact hole pattern width (0.3 μm) is obtained. ). Further, the difference between the center of the peak of the light intensity distribution curve and the center of the peak of the light intensity distribution curve obtained from the halftone phase shift mask without the defect region 14 is 0.0.
It was less than 1 μm.

The defect area 14 in this Embodiment 6 can be repaired in the same manner as in Embodiment 1 or Embodiment 2, and detailed description thereof will be omitted.

(Modification of Example-6 [Part 3]) This modification of Example-6 is carried out except that the structure of the halftone phase shift mask is different from the modification [Part 1] of Example-6. It is substantially the same as the modification [No. 1] of Example-6. This halftone type phase shift mask comprises a substrate 20 made of, for example, quartz, and a semi-shielded region 12 formed thereon. The semi-light-shielding region 12 is composed of a semi-light-shielding layer 22 made of chromium and a light-transmitting material layer 26 (so-called shifter) made of, for example, SOG formed between the semi-light-shielding layer 22 and the substrate 20. The phase difference between the light passing through the light transmitting region 10 and the light passing through the semi-shielded region 12 is, for example, 180 °. The defect area 14 is formed by the light transmitting material layer 26.
It is a defect in which a part of is missing. Such a defect area 14 is likely to occur when the light-transmitting area 10 is formed by etching the semi-light-shielding layer 22 and the light-transmitting material layer 26 formed on the substrate 20.

25A and 25B are schematic partial sectional views of a halftone phase shift mask obtained by modifying the halftone phase shift mask shown in FIG. 25A by the same method as in Example-1. B). 25C is a schematic partial cutaway view of a halftone phase shift mask modified by the same method as in Example-2.

(Modification [Example 4] of Example-6) The halftone phase shift mask of the modification of Example-6 is as follows.
It has the same structure as the modification [3] of the example-6. The form of defects in this halftone phase shift mask is substantially the same as the modification [2] of Example-6.

26A is a schematic partial cutaway view of a halftone type phase shift mask in which the halftone type phase shift mask shown in FIG. 26A is modified by the same method as in Example-1. B). A schematic partial cutaway view of the halftone phase shift mask modified by the same method as in Example-2 is shown in FIG.

Although a part of the embodiment 6 has been described by taking the case where the light transmitting substance layer 26 is thick as an example, it can be similarly corrected when the light transmitting substance layer 26 is thin.

The present invention has been described above based on the preferred embodiments, but the present invention is not limited to these embodiments. The conditions and numerical values described in the examples are examples,
It can be changed appropriately. The shapes and sizes of the light transmission region 10 and the defect region 14 are examples.

The size, shape and position of the defective region, exposure wavelength, exposure conditions, etc., such as the size of the repair region 16 or the portion 10A of the light transmitting region adjacent to the repair region 16 and the amplitude transmittance of the light shielding portion, etc. Can be changed as appropriate. As long as the transfer pattern shape is not affected, a part of the defect area 14 may protrude from the repair area 16 in some cases.

In each of the embodiments, the defect area 14 adjacent to the contact hole pattern has been described, but the present invention is not limited to the contact hole pattern. The present invention can be applied to all kinds of device patterns very easily. Further, the defect region 14 does not necessarily have to be adjacent to the light transmission region 10, and may be present in the vicinity of the light transmission region 10 as illustrated in FIG. 28 or 29.

FIG. 28 shows a defect form similar to that shown in FIG. 11, and a schematic partial plan view of the halftone phase shift mask 1 including the defect region 14 is shown in FIG.
FIG. 28B is a partially cutaway view. FIG. 28C is a partial cross-sectional view of the halftone phase shift mask 1A modified by the same method as in Example-1.

FIG. 29 shows a defect form similar to that shown in FIG. 17, and a schematic partial plan view of the halftone phase shift mask 1 including the defect region 14 is shown in FIG.
FIG. 29B is a partially cutaway view. FIG. 29C is a partial cross-sectional view of the halftone phase shift mask 1A modified by the same method as in Example 1, and the halftone phase shift mask modified by the same method as in Example 2 is shown in FIG. 29C. A partially cutaway view of 1B is shown in FIG.

The light shield 30 or the first and second light shields 32 and 3 depending on the position or shape of the defect area.
The formation regions of No. 4 may be set appropriately. In this case, the light-shielding body 30 or the first and second light-shielding bodies 32, 34 formed on the repaired region 16 and the part 10A of the light-transmitting region adjacent to the repaired region 16 is shown in FIG. 29 may be integrated, or may be separate as shown in FIG. 29 (C) or (D).

A laser beam, an electron beam or the like may be used as the means for forming the light shield, but it is preferable to use a focused ion beam so that the light shield can be formed with good control. A Ga ⁺ ion beam was used as the focused ion beam in forming the light shield, but the ion beam is not limited to this, and any ion beam can be used as long as it can form the light shield. . Further, although pyrene gas was used as the carbon-containing gas to form the light shield, the gas is not limited to pyrene gas, and any gas containing carbon can be used.

The semi-light-shielding layer can be made of a material other than chromium, which can shield an appropriate amount of light. In addition to carbon, the light-shielding body may be made of any material having a light-shielding function such as chromium, chromium oxide, chromium oxide laminated on chromium, refractory metal (W, Mo, Be, etc.). The formation method can be appropriately selected depending on the material used. For example,
It can be composed of Cr, Mo, W or an oxide thereof formed by the laser CVD method. The light transmitting material layer 26 is not limited to SOG, and may be polymethylmethacrylate, magnesium fluoride, titanium dioxide, polyimide resin, silicon dioxide, indium oxide, SiO ₂ , SiN,
Any transparent material such as various resists may be used.

The amplitude transmittance of the semi-shielded area 12 is not limited to 40%, and may be any value larger than 0% and smaller than 55%. The amplitude transmittance of the second light shield 34 formed on the part 10A of the light transmission area adjacent to the correction area 16 is not limited to 20%, and may be a value larger than 0% and smaller than 100%. If there is, 0%
It is desirable to choose an amplitude transmittance greater than 50% and less than 50%. The amplitude transmittance was measured using a spectrum photometer U-3200 manufactured by Hitachi, Ltd. In addition, the transmitted light intensity is measured when the intensity of the light transmitted through the light transmitting region at the exposure wavelength is set to 1, and this is defined as the light intensity transmittance. The amplitude transmittance is the square root of the light intensity transmittance.

In the example 1 and the like, the correction area 16
A portion 10 of the light-transmitting region adjacent to the top and the correction region 16
The light transmittance of the light shield 30 formed on A is the same.
Further, in Example-2 and the like, the second light shield 3 formed on the part 10A of the light transmission region adjacent to the correction region 16 is formed.
4 and the amplitude transmittance of the first light shield 32 formed on the correction region 16 was changed. However, the same effect can be obtained by appropriately and continuously changing the amplitude transmittance of these light shields.

[0159]

According to the present invention, the defective area can be repaired without strictly depending on the size and shape of the defective area. That is, it is possible to correct the defective area with a high correction margin with normal correction accuracy. Further, the defective area can be repaired regardless of the form of the defect. Moreover, it is possible to prevent the transfer of the defective area to the resist material and the deterioration of the depth of focus due to the light exposure.

Further, since a part of the light transmitting area adjacent to or close to the correction area is covered with the light shield, the change of the transfer pattern shape from the desired pattern shape which occurs when only the correction area is covered with the light shield. Can be corrected. In addition, by accurately controlling the width, position, or transmittance of the light shield and all of these, a desired transfer pattern shape and a sufficient depth of focus can be obtained accurately.

Further, by appropriately preliminarily determining the position and size of the light shield with respect to the correction area by experiments, calculations, etc., and accurately controlling the obtained position and size of the light shield, a desired light shield can be obtained. The transfer pattern shape can be efficiently and accurately obtained.

According to the present invention, the halftone type phase shift mask can be easily and simply modified, the throughput of the halftone type phase shift mask is improved, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a halftone phase shift mask including a defective region in Example-1.

FIG. 2 is a schematic diagram of a halftone phase shift mask in which a defective area is corrected in Example-1.

FIG. 3 is a halftone phase shift mask before correction,
7A and 7B are diagrams showing a light intensity distribution of light that has passed through the modified halftone phase shift mask in Example-1.

FIG. 4 is a diagram showing a correction area in Example-1.

5A and 5B are schematic partial cross-sectional views of a halftone phase shift mask before and after modification of Example-1 having a structure different from the structure shown in FIG.

FIG. 6 is a schematic diagram of a halftone phase shift mask in which a defective area is corrected in Example-2.

FIG. 7 is a diagram showing a light intensity distribution of light passing through a modified halftone phase shift mask in Example-2.

8A and 8B are schematic partial cutaway views of a halftone phase shift mask before and after modification of Example-2 having a structure different from the structure shown in FIG.

FIG. 9 is a schematic diagram of a halftone phase shift mask including a defective region in Example-3.

FIG. 10 is a schematic diagram of a halftone phase shift mask including a defective region in Example-4.

FIG. 11 is a schematic diagram of a halftone phase shift mask in which a defective area is corrected in Example-4, which is corrected based on the correction method described in Example-1.

FIG. 12 is a diagram showing a light intensity distribution of light that has passed through a halftone phase shift mask before correction in Example-4.

FIG. 13 is a schematic view of a modified halftone phase shift mask of Example-4, which is modified based on the modification method described in Example-2.

FIG. 14 is a schematic partial cutaway view of a halftone phase shift mask before and after modification of Example-4 having a structure different from the structure shown in FIG. 10;

FIG. 15 is a schematic partial cutaway view of a halftone phase shift mask before and after modification of Example-4 having a structure different from the structure shown in FIG.

FIG. 16 is a schematic view of a halftone phase shift mask including a defective region in Example-5.

FIG. 17 is a schematic view of a halftone phase shift mask in which a defect area in Example-5 has been corrected, which is corrected based on the correction method described in Example-1.

FIG. 18 is a diagram showing a light intensity distribution of light that has passed through a halftone phase shift mask before being modified in Example-5.

FIG. 19 is a schematic view of a modified halftone phase shift mask of Example-5, which is modified based on the modification method described in Example-2.

FIG. 20 is a schematic partial cutaway view of a halftone phase shift mask before and after modification of Example-5 having a structure different from the structure shown in FIG. 16;

21 is a schematic partial cutaway view of a halftone phase shift mask before and after correction in Example-5 having a structure different from the structure shown in FIG. 20. FIG.

FIG. 22 is a schematic view of a halftone phase shift mask including a defective area in Example-6.

FIG. 23 is a schematic diagram of a halftone phase shift mask in which a defect area in Example-6 has been corrected, which is corrected based on the correction method described in Example-1.

FIG. 24 is a schematic view of a halftone phase shift mask in which a defective area is corrected in Example-6, which is corrected based on the correction method described in Example-1 and Example-2.

FIG. 25 is a schematic diagram of a halftone phase shift mask in which a defective area is corrected in Example-6, which is corrected based on the correction method described in Example-1 and Example-2.

FIG. 26 is a schematic diagram of a halftone phase shift mask in which a defective area is corrected in Example-6, which is corrected based on the correction method described in Examples-1 and-2.

FIG. 27 is a diagram showing a light intensity distribution of light that has passed through a halftone phase shift mask before being corrected in Example-6.

FIG. 28 is a schematic diagram showing a defect and its correction when the defect region 14 exists near the light transmission region 10.

FIG. 29 is a schematic diagram showing a defect and its correction when the defect region 14 exists near the light transmission region 10.

FIG. 30 is a diagram showing a structure of a conventional phase shift mask.

FIG. 31 is a diagram showing the structure of a conventional halftone phase shift mask.

FIG. 32 is a diagram showing a defect in a conventional halftone phase shift mask.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Halftone type phase shift mask 10 Light transmission area 10A Part of light transmission area adjacent to or adjacent to correction area 16 10B Part of substrate 12 Semi-light-shielding area 14 Defect area 16 Correction area 18 Light-shielding area 20 Substrate 22 Semi-light-shielding layer 24 Phase shift region 26 Light transmissive material layer 30 Light shield 32 First light shield 34 Second light shield

Claims (23)

[Claims] 1. A halftone phase shift mask comprising a semi-shielding region and a light transmitting region, wherein the phase of light passing through the semi-shielding region and the phase of light passing through the light transmitting region are different from each other. Amplitude transmittance, or both of them differ from a predetermined value, and include a defect region existing in a semi-shielded region adjacent to or close to a light transmission region, and a repair region in the defect region larger than the defect region, and A halftone phase shift mask, characterized in that a part of a light transmission region adjacent to or close to the correction region is covered with a light shield having an amplitude transmittance that does not expose the resist material to light. 2. The transfer pattern shape to the resist material obtained by the modified halftone phase shift mask is substantially the same as the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect region. The position and shape of a part of the light transmission region adjacent to or close to the correction region, and further, the amplitude transmittance of the light shield is selected as necessary so as to coincide with each other. Halftone type phase shift mask. 3. The halftone phase shift mask according to claim 1, wherein the light shield is made of carbon. 4. The correction region is covered with a first light shield having an amplitude transmittance that does not expose the resist material to light, and a part of the light transmission region adjacent to or close to the correction region is the first light shield. The halftone phase shift mask according to claim 1, wherein the halftone phase shift mask is covered with a second light shield having an amplitude transmittance different from the amplitude transmittance of the. 5. The transfer pattern shape to the resist material obtained by the modified halftone phase shift mask is substantially the same as the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defect region. 5. The position and shape of a part of the light transmission region adjacent to or close to the correction region, and further, the amplitude transmittance of the second light shield is selected so as to coincide with each other. Halftone type phase shift mask described in. 6. The halftone phase shift mask according to claim 4, wherein the first or second light shield is made of carbon. 7. The semi-light-shielding region comprises at least a semi-light-shielding layer, and the defect region has at least a semi-light-shielding layer missing or at least a thickness of the semi-light-shielding layer different from a predetermined value. 7. The halftone phase shift mask according to claim 6. 8. The semi-shielded region is larger than 0 and equal to or less than 0.
The halftone phase shift mask according to any one of claims 1 to 7, which has an amplitude transmittance smaller than 55. 9. A halftone phase shift mask comprising a semi-shielding region and a light transmitting region, wherein a phase of light passing through the semi-shielding region and a phase of light passing through the light transmitting region are different from each other. When a defect area in which the ratio or both of them is different from a predetermined value is present in the semi-shielded area adjacent to or close to the light transmission area, the defect area is included in the semi-shielded area and A halftone characterized in that a large repair area is selected, and the repair area and a part of the light transmission area adjacent to or close to the repair area are covered with a light shield having an amplitude transmittance that does not expose the resist material to light. Method of correcting phase shift mask. 10. A transfer pattern shape to a resist material obtained by a modified halftone phase shift mask is substantially the same as a transfer pattern shape to a resist material obtained by a halftone phase shift mask when there is no defect region. 10. The half according to claim 9, wherein the position and shape of a part of the light transmission region adjacent to or close to the correction region, and further, the amplitude transmittance of the light shield are selected so as to coincide with each other. Tone type phase shift mask repair method. 11. The method of modifying a halftone phase shift mask according to claim 9, wherein the light shield is made of carbon. 12. The correction region is covered with a first light shield having an amplitude transmittance that does not expose the resist material to light, and a part of the light transmission region adjacent to or close to the correction region is covered by the first light shield. 10. The method of modifying a halftone phase shift mask according to claim 9, further comprising: covering with a second light shield having an amplitude transmittance different from the amplitude transmittance of the halftone phase shift mask. 13. A transfer pattern shape to a resist material obtained by a modified halftone phase shift mask is substantially the same as a transfer pattern shape to a resist material obtained by a halftone phase shift mask when there is no defect region. 13. The position and shape of a part of the light transmission region adjacent to or close to the correction region, and further, the amplitude transmittance of the second light shield is selected as necessary so as to coincide with each other. A method for correcting the described halftone phase shift mask. 14. The method of modifying a halftone phase shift mask according to claim 12, wherein the first or second light shield is made of carbon. 15. The semi-light-shielding region comprises at least a semi-light-shielding layer, and the defect region has at least a semi-light-shielding layer missing or at least a thickness of the semi-light-shielding layer different from a predetermined value. 15. A method of correcting a halftone phase shift mask according to claim 14. 16. The halftone phase shift according to claim 9, wherein the semi-shielded region has an amplitude transmissivity larger than 0 and smaller than 0.55. How to fix the mask. 17. A halftone phase shift mask comprising a semi-shielding region and a light transmitting region, wherein a phase of light passing through the semi-shielding region and a phase of light passing through the light transmitting region are different from each other. When a defect area in which the ratio or both of them is different from a predetermined value is present in the semi-shielded area adjacent to or close to the light transmission area, the defect area is included in the semi-shielded area and In a halftone phase shift mask, a large correction area is selected, and the correction area and a part of the light transmission area adjacent to or close to the correction area are covered with a light shield having an amplitude transmittance that does not expose the resist material to light. A correction method, which is a transfer pattern to a resist material obtained by a modified halftone phase shift mask based on the selected correction region. Position of a part of the light transmission area adjacent to or close to the correction area so that the shape of the light transmission area substantially matches the shape of the transfer pattern to the resist material obtained by the halftone phase shift mask when there is no defect area. A method for correcting a halftone phase shift mask, characterized in that the shape and, if necessary, the amplitude transmittance of the light shield are obtained by simulation or calculation. 18. The method of modifying a halftone phase shift mask according to claim 17, wherein the light shield is made of carbon. 19. The correction area is covered with a first light shield having an amplitude transmittance that does not expose a resist material to light, and a part of the light transmission area adjacent to or close to the correction area is covered by the first light shield. A transfer pattern shape onto a resist material, which is covered with a second light shield having an amplitude transmittance different from the amplitude transmittance possessed, and which is obtained by a modified halftone phase shift mask based on the selected repair area. However, the position and shape of a part of the light transmission area adjacent to or close to the correction area, so as to substantially match the transfer pattern shape to the resist material obtained by the halftone phase shift mask when there is no defective area, 18. The half screen according to claim 17, wherein the amplitude transmissivity of the second light shield is calculated as necessary by simulation or calculation. How to fix emissions system phase shift mask. 20. The method of correcting a halftone phase shift mask according to claim 19, wherein the first or second light shield is made of carbon. 21. The semi-light-shielding region comprises at least a semi-light-shielding layer, and the defective region has at least the semi-light-shielding layer missing or at least the thickness of the semi-light-shielding layer is different from a predetermined value. 21. A method of modifying a halftone phase shift mask according to claim 20. 22. The halftone phase shift according to claim 17, wherein the semi-shielded region has an amplitude transmittance greater than 0 and less than 0.55. How to fix the mask. 23. A halftone type phase shift mask is formed by exposing a resist material formed on a wafer using the halftone type phase shift mask according to any one of claims 1 to 8. A method of manufacturing a semiconductor device, which comprises transferring the formed pattern shape to a resist material.