JP2006330270A - Method for preparing mask data, method for manufacturing mask and method for manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for preparing a mask data by which the delay of mask manufacturing schedule is suppressed when the mask data is prepared by applying an optical proximity correction to a design data. <P>SOLUTION: The method for preparing the mask data comprises steps: to make a correction including the optical proximity correction on the design data of a pattern of a device to be formed on a substrate (S11); to judge whether the corrected design data contains any obstructive graphic with a minute dimension, which hinders mask manufacturing although which does not affect characteristics of the device, or not (S13); and to correct the obstructive graphic so as not to be the obstructive graphic with the minute dimension, which hinders mask manufacturing, when it is judged that the corrected design data includes a certain obstructive graphic (S14). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method of creating mask data used for manufacturing a photomask, a method of manufacturing a mask using the mask data, and a method of manufacturing a semiconductor device using a mask manufactured by the manufacturing method.

  Along with the miniaturization of semiconductor devices, a decrease in pattern fidelity and dimensional variation due to the optical proximity effect have become major problems in the semiconductor manufacturing process.

In order to solve such problems, an optical proximity effect correction (OPC) that modifies the pattern of the design data so that a desired pattern can be obtained when the pattern formed on the photomask is transferred onto the wafer. Correction) is generally implemented. Various methods have been proposed and implemented for optical proximity correction (hereinafter abbreviated as OPC).
Usually, necessary graphic processing such as OPC is automatically performed on design data to generate mask data. In the process of these graphic processes, fine irregularities, acute irregularities, and figures having opposite sides and diagonals in close proximity are generated on the mask data. These figures are often figures that do not affect device characteristics.

  However, the figure induces several problems in the photomask manufacturing process. Hereinafter, this problem will be further described.

  When the figure is so small that it cannot be formed on the photomask, a useless pattern is drawn at the time of mask drawing. This leads to an increase in drawing time. Furthermore, when the data including the minute figure is used, the pattern that should exist on the data does not exist on the photomask in the step of performing the defect inspection by the data comparison inspection apparatus. A region on the photomask is detected as a pseudo defect (inspection noise). Therefore, the minute figure increases the time required for pattern confirmation and delays the mask construction period.

  On the other hand, even if the figure is a figure that can be formed on a photomask, if the figure is so small that the guarantee of the formation accuracy cannot be maintained, the pattern cannot be formed accurately. Therefore, the figure is highly likely to be detected as a pseudo defect in all mask inspection apparatuses. Therefore, in this case as well, the above-mentioned figure becomes a factor for delaying the mask construction period.

  Furthermore, when a figure smaller than the pattern size that can be stably inspected by the mask inspection apparatus or a figure lower than the resolution of the inspection apparatus exists on the photomask, these figures are highly likely to be detected as pseudo defects. . When the number of such small small figures is large, the time required for pattern confirmation becomes long. Therefore, the increase in the figure is not preferable because it delays the mask construction period and also causes the operator to perform useless work.

  In order to reduce such adverse effects such as minute figures, a pattern correction method is known in which a slight bias process is applied to the entire layout data after OPC to erase minute irregularities. Further, there has been proposed a pattern correction method for efficiently correcting a minute side existing in a design pattern without causing unnecessary unevenness (Patent Document 1).

However, when the mask data corrected by these pattern correction methods is used to actually manufacture a photomask for a device with advanced fineness, and when the manufactured photomask is inspected, a minute figure that becomes a pseudo defect There are many. Therefore, the above conventional pattern correction method is insufficiently corrected from the viewpoint of mask manufacturing.
JP 2003-195473 A

  An object of the present invention is to provide a mask data generation method, a mask manufacturing method, and a semiconductor device manufacturing method capable of suppressing a delay in a mask construction period when mask data is generated by performing optical proximity effect correction on design data. .

  A mask data creation method according to the present invention includes a step of performing correction including optical proximity effect correction on design data of a pattern of a device formed on a wafer, and the design data subjected to the correction includes: Although there is no effect on the characteristics, in the case of determining whether to include an obstacle graphic having a minute dimension that becomes an obstacle in mask manufacturing, and when the design data subjected to the correction is determined to include an obstacle graphic, And a step of correcting the obstruction graphic so that it does not become an obstruction figure having a minute dimension which becomes an obstacle in manufacturing the mask.

  Another mask data generation method according to the present invention includes a step of performing correction including optical proximity effect correction on design data of a device pattern formed on a wafer, and the design data subjected to the correction includes Although there is no effect on the device characteristics, the step of determining whether or not a failure figure having a minute dimension that hinders mask manufacturing is included, and the case where it is determined that the corrected design data includes an obstacle figure Includes a step of determining a mask inspection sensitivity in which a region on the mask corresponding to the obstacle figure is not detected as a pseudo defect.

  The mask manufacturing method according to the present invention includes a step of creating mask data using the mask data creation method according to the present invention, and exposing a resist film applied on a substrate including a transparent substrate based on the mask data. And a step of developing the exposed resist film, and a step of etching the substrate using the resist film remaining after the development as a mask.

  A method of manufacturing a semiconductor device according to the present invention includes a step of exposing a resist film applied on a substrate including a wafer, a step of developing the exposed resist film, and the development using the mask according to the present invention. And etching the substrate using the remaining resist film as a mask.

  According to the present invention, it is possible to realize a mask data creation method, a mask manufacturing method, and a semiconductor device manufacturing method capable of suppressing a delay in a mask construction period when mask data is generated by performing optical proximity effect correction on design data. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a flowchart showing a mask rule table creation method of the present embodiment. FIG. 2 is a flowchart showing a mask data creation method using this mask rule table.

  First, mask data in which test figures and evaluation figures are arranged is created, and a test mask is produced using the mask data (step S1).

  On the test mask, a test pattern corresponding to the test graphic and an evaluation pattern corresponding to the evaluation graphic are arranged. The evaluation pattern is a pattern for evaluating the basic pattern formation limit and the formation accuracy on the mask.

  The test figure is a figure having a minute dimension. Further, the test figure includes a plurality of figures shown in FIG. 3 to FIG. 7 in which the figure size is assigned to each figure shape (category). The evaluation figure includes a plurality of figures shown in FIGS. 8 and 9 in which the figure size is categorized according to the figure shape (category).

  The test figure in FIG. 3 shows a plurality of minute projections and minute depressions (minute irregularities) having different figure sizes. The figure size of the minute protrusion is defined by the height H and width W of the protrusion. The figure size of the minute recess is defined by the depth H and width W of the recess. The cross-sectional shape of the convex portion in FIG. 3 is a rectangle, but it may be a triangle (acute convex shape). Similarly, the shape of the concave portion may be a triangle (acute concave shape).

  The test figure in FIG. 4 shows a plurality of adjacent diagonal parts (adjacent adjacent diagonal parts) having different graphic sizes and whose diagonals are extremely close to each other. The figure size is defined by the diagonal distance L1.

  The test figure in FIG. 5 shows a plurality of figures of different sizes, the opposite sides of which are very close (adjacent adjacent opposite sides). The figure size is defined by the distance L2 between opposite sides.

  The test figures in FIGS. 6 and 7 show inversion patterns of the test figures in FIGS. 4 and 5, respectively. In the case of FIGS. 6 and 7, the figure size is defined by distances L1 and L2, respectively.

  The evaluation figure in FIG. 8 shows a plurality of line patterns, L & S patterns, and line pattern inversion patterns having different figure sizes. The figure size is defined by the width D of Space / Line.

  The evaluation graphic in FIG. 9 shows a plurality of isolated CHs (Contact Holes) having different graphic sizes and two-dimensional CHs arranged in a matrix. The figure size of the isolated CH is defined by its diameter R. The figure size of the two-dimensional CH is defined by the opposite side distance Gx between the CHs adjacent in the horizontal direction, the opposite side distance Gy between the CHs adjacent in the vertical direction, and the inter-corner distance Gz between the CHs adjacent in the diagonal direction.

  Next, the dimension of each evaluation pattern on the actually produced test mask is measured (step S2). The measurement of the test mask is performed using a known measuring device.

  Next, based on the measured dimension (finished value) of each evaluation pattern, the size of each evaluation graphic (formation limit graphic size) corresponding to each evaluation pattern that can no longer be formed on the mask is determined (step S3). An evaluation figure having a size equal to or smaller than the formation limit figure size becomes an obstacle figure having a minute dimension that becomes an obstacle in mask manufacturing.

  The formation limit graphic size is defined by, for example, the graphic size (first graphic size) of the evaluation graphic corresponding to the evaluation pattern that cannot be formed on the mask first. Furthermore, the formation limit graphic size can be defined to be smaller than the graphic size (second graphic size) of the evaluation graphic corresponding to the test pattern having the minimum finished dimension that can be formed on the mask. Furthermore, an average value of the first graphic size and the second graphic size may be adopted.

  Next, each test pattern on the actually created test mask is inspected by the mask inspection apparatus (step S4). This test mask inspection is performed, for example, by the mask defect inspection apparatus shown in FIG.

  In FIG. 10, reference numeral 11 denotes an XY table for placing a mask 12 used in manufacturing a semiconductor device. This XY table 11 is generated by a stage control circuit 14 that receives a command from a computer 13, It is driven in the direction and the Y direction perpendicular thereto.

  The movement position of the XY stage 11 is monitored by a laser interferometer (not shown). The position information of the XY stage 11 is input to the stage control circuit 14. The stage control circuit 14 controls the XY stage 11 on which the mask 12 is placed with high accuracy.

  On the other hand, a light source 15 is disposed above the XY stage 11. The light (irradiation light) emitted from the light source 15 is irradiated on the mask 12 placed on the XY stage 11. Irradiated light (transmitted light) that has passed through the mask 12 forms an image on the light receiving surface of an imaging device 16 typified by a CCD sensor. For example, the imaging device 16 includes a plurality of light receiving sensors arranged in a line.

  When the XY stage 11 is continuously moved in the direction (Y direction) orthogonal to the reading direction (X direction) of the light receiving sensor together with the light irradiation, a detection analog signal corresponding to the formation pattern of the mask 12 is generated by the imaging device 16. To be acquired.

  The detected analog signal is converted into a digital signal (detected digital signal) by the AD converter 17 in accordance with an instruction from the computer 13. The detection digital signal is sent from the AD converter 17 to the comparison circuit 20.

  On the other hand, mask pattern data (pattern design data) 10 serving as a basis for forming a mask pattern to be inspected is input to the computer 13. The mask pattern data 10 is sent from the computer 13 to the pattern development circuit 18. The pattern development circuit 18 develops the mask pattern data 10 into development data. The development data is sent from the pattern development circuit 18 to the reference data generation circuit 19. The reference data generation circuit 19 creates a reference digital signal obtained by converting the mask pattern data 10 in the region corresponding to the detected analog signal detected by the imaging device 16 into a signal format that can be compared with the detected digital signal. The reference digital signal is sent from the reference data generation circuit 19 to the comparison circuit 20.

  The comparison circuit 20 compares the reference digital signal and the detected digital signal according to an appropriate algorithm, and if they do not match, determines that there is a pattern defect and outputs defect data.

  By repeating the above-described series of defect inspections, that is, the reading scan of the imaging device 16 and the continuous movement operation of the XY stage 11 on which the mask 12 is placed are repeatedly performed, and the detection digital signal of each inspection area on the mask 12 is detected. The mask 12 is inspected by comparing the reference digital signal with the reference digital signal.

  Next, based on the result of the defect inspection, the shape and size of the test figure corresponding to the test pattern detected as a pseudo defect is checked, and the figure size range that becomes a pseudo defect for each test figure shape (category) ( A pseudo defect figure size range) is determined (step S5). The test figure within the pseudo defect figure size range becomes an obstacle figure having a minute dimension that becomes an obstacle in manufacturing the mask.

  When the mask defect inspection apparatus shown in FIG. 10 is used, a pattern portion that is not actually a defect but has a large difference between the reference digital signal and the detected digital signal and a signal difference of a predetermined level or more is detected as a pseudo defect. . Therefore, it is desirable that the test mask inspection (step S4) is repeated several times, and the pseudo defect figure size range is determined (step S5) in consideration of the detection reproducibility of the pseudo defects.

  The formation limit figure size and the pseudo defect figure size range are not limited to those described above.

  In other words, it corresponds to the figure on the mask data corresponding to the isolated pattern having a dimension that cannot be formed on the mask, and to the isolated pattern having a dimension that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy on the mask. The figure on the mask data, the figure on the mask data corresponding to the isolated pattern on the mask detected as a pseudo defect by the mask inspection apparatus, and the pattern including two adjacent patterns having a distance that cannot be formed on the mask Corresponding figure on mask data, figure on mask data corresponding to a pattern including two adjacent patterns that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy on the mask, mask inspection Mask data corresponding to a pattern including two adjacent patterns on a mask having a distance detected as a pseudo defect by the apparatus The figure on the mask corresponding to the pattern on the mask and the pattern that cannot be formed on the mask, and the pattern on the mask that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy. As long as it includes at least one of the figure on the mask data corresponding to the above and the figure on the mask data corresponding to the concavo-convex pattern on the mask detected as a pseudo defect by the mask inspection apparatus. Which of these is adopted is case by case.

  The steps S2-S5 do not need to be performed in the order of step S2, step S3, step S4, and step 5, and can be changed as appropriate. For example, step S4, step 5, step S2, and step S3 may be performed in this order. Furthermore, after performing in order of step S2 and step S4, step S3 and step S5 may be performed simultaneously. Furthermore, after performing in order of step S4 and step S2, step S3 and step S5 may be performed simultaneously.

  Then, the combination of the shape of the obstacle graphic (evaluation graphic) determined in step S2 and the formation limit graphic size, and the combination of the shape of the obstacle graphic (test graphic) determined in step S5 and the pseudo defect graphic size range are registered. The mask rule table thus created is created (step S6).

  Next, a mask data creation method using the mask rule table will be described. The mask rule table is prepared in advance for each required specification accuracy of the mask to be created, prepared in advance for each mask manufacturing apparatus used at the time of mask creation, or newly formed for each required specification accuracy of the mask to be created. Alternatively, it is newly formed for each mask manufacturing apparatus used when creating a mask.

  First, correction including OPC is performed on the design data of the pattern of the device formed on the wafer (step S11).

  Next, the obstacle graphic is detected for the design data subjected to the above correction (step S12), and the presence / absence of the obstacle graphic is determined (step S13). These are performed by comparing and collating the design data subjected to the correction with the mask rule table.

  In the case of the mask rule table obtained by the creation method of FIG. 1, the figure corresponding to the obstacle figure is a figure on the design data subjected to the above correction corresponding to an isolated pattern having a dimension that cannot be formed on the mask. In the pattern including the figure on the design data subjected to the above correction corresponding to the isolated pattern on the mask detected as a pseudo defect by the mask inspection apparatus, and two adjacent patterns having a distance that cannot be formed on the mask On the design data subjected to the above correction corresponding to the pattern including the two adjacent patterns on the mask having a distance detected as a pseudo defect by the mask inspection apparatus However, it is not limited to this.

  That is, the obstacle graphic is a figure on the mask data corresponding to an isolated pattern having a dimension that cannot be formed on the mask, and a dimension that can be formed on the mask but cannot be formed on the mask with a predetermined dimensional accuracy. The figure on the mask data corresponding to the isolated pattern having, the figure on the mask data corresponding to the isolated pattern on the mask detected as a pseudo defect by the mask inspection apparatus, and two adjacent ones having a distance that cannot be formed on the mask Figure on mask data corresponding to the pattern including the pattern, on mask data corresponding to the pattern including two adjacent patterns that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy on the mask For a pattern including two adjacent patterns on a mask having a distance detected as a pseudo defect by a mask inspection apparatus The figure on the mask data, the figure on the mask data corresponding to the concavo-convex pattern having a dimension that cannot be formed on the mask, and the dimension that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy. It is only necessary to include at least one of a figure on the mask data corresponding to the concavo-convex pattern and a figure on the mask data corresponding to the concavo-convex pattern on the mask detected as a pseudo defect by the mask inspection apparatus.

  In step S13, when it is determined that the design data subjected to the correction includes an obstacle graphic registered in the mask rule table, so as not to be an obstacle graphic having a minute dimension that becomes an obstacle in mask manufacturing, The obstacle graphic is corrected (step S14). Examples of the correction include deleting, deforming (reducing), and moving the obstacle graphic.

  At this time, it is preferable that the obstacle graphic included in the corrected design data is erased or corrected and deformed in consideration of the transfer characteristics onto the wafer. The transfer characteristic onto the wafer is, for example, whether or not desired device characteristics can be obtained with a pattern transferred onto the wafer. As a result of considering the transfer characteristics onto the wafer, there is a case where the erasure pattern correction processing or correction deformation processing is not performed.

  FIG. 11 shows an example of a minute convex portion (obstacle figure) 31 in the design data (hereinafter referred to as post-OPC design data) 30 that has been detected using the mask rule table and has been subjected to the above correction. FIG. 12 shows an example in which correction for deleting the minute convex portion 31 is performed. The correction for deleting the minute convex portion 31 is performed on the post-OPC design data 30. That is, data (for example, drawing data) corresponding to the minute convex portion 31 can be corrected without returning to the design data.

  FIG. 13 shows an example of the adjacent adjacent diagonal portion 32 in the post-OPC design data 30 detected using the mask rule table. FIG. 14 shows how to correct the adjacent adjacent diagonal portion 32. In this case, one or both of the two adjacent figures 33 and 34 are reduced (deformed) in the horizontal direction (X direction), the vertical direction (Y direction) or the horizontal and vertical directions, or the horizontal direction and the vertical direction. Alternatively, they are translated in the horizontal and vertical directions. Further, reduction and translation are performed. The direction of deformation / movement is determined in consideration of another figure (not shown) around two adjacent figures 33 and 34. The correction of the adjacent adjacent diagonal portion 32 is generally performed on the design data.

  After correcting the obstacle graphic, the presence or absence of the obstacle graphic is determined again using the mask rule table check. Until it is determined that there is no obstacle graphic, the correction of the obstacle graphic (step S14) and the determination of the presence or absence of the obstacle graphic (step S13) are repeated.

  If it is determined in step S13 that there is no obstacle graphic, mask data is created based on the post-OPC design data that is determined to have no obstacle graphic (step S15).

  By manufacturing a mask using the mask data created in this way, the number of figures on the mask data corresponding to a useless pattern that cannot be resolved in advance on the mask, or a pattern that is likely to become a pseudo defect in the mask inspection apparatus. The number of figures on the corresponding mask data is sufficiently reduced. As a result, the mask fabrication troubles such as the mask drawing time and the mask inspection process are reduced, and the mask construction period can be shortened.

  By the way, when an obstacle figure cannot be corrected appropriately in step S14, the loop processing of steps S12, S13, and S14 is performed infinitely. In other words, the detected obstacle graphic may not be corrected in order to maintain the transfer characteristic on the wafer or the device characteristic, or a correction error may occur. In preparation for such a case, the maximum number of loop processes in steps S12, S13, and S14 is determined in advance. When the loop processing reaches the maximum number of times, information (for example, coordinates) of the obstacle graphic that could not be corrected is acquired. Together with the mask data, this information is provided to the mask manufacturing process.

  In the mask manufacturing process, the information on the obstacle figure and the mask data that could not be corrected are input to the mask inspection apparatus, and the coordinates of the pattern detected as a pseudo defect as a result of manufacturing and inspecting the mask are input in advance. When the coordinates of the obstacle graphic are compared, and the two coordinates match, the pattern is automatically set to be ignored instead of being a defect. As a result, it is possible to reduce the work load for the operator to confirm the pseudo defect, and as a result, the mask construction period can be shortened.

  The mask manufacturing method of this embodiment is as follows.

  First, mask data is created by the method described above.

  Next, using the mask data, a pattern is drawn on the resist in the mask blank substrate by an EB drawing apparatus. The mask blank substrate includes a quartz substrate, a light shielding film (here, a Cr film) formed on the quartz substrate, and a resist formed on the light shielding film. The pattern is a pattern corresponding to the light shielding film pattern.

  Next, the resist is developed to form a resist pattern, and the light shielding film is etched using the resist pattern as a mask to form a light shielding film pattern. Thereafter, the resist pattern is removed. In this way, a mask including a light shielding film pattern is obtained.

  In the case of a mask including a light shielding film pattern and a translucent film pattern, the following steps are further continued.

  A semi-transparent film is formed on the entire surface of the quartz substrate and the light-shielding film pattern, a resist is applied on the semi-transparent film, and a pattern is drawn on the resist by an EB drawing apparatus using the mask data. The pattern is a pattern corresponding to the semitransparent film pattern.

  Next, the resist is developed to form a resist pattern, and the semitransparent film is etched using the resist pattern as a mask to form a semitransparent film pattern. Thereafter, the resist pattern is removed. Through the above steps, a photomask including a light shielding film pattern and a semitransparent film pattern is obtained.

  The manufacturing method of the semiconductor device of this embodiment is as follows.

  First, a resist film applied on a substrate including a wafer is exposed. The substrate including the wafer is, for example, the wafer itself, a substrate including the wafer and the insulating film, a substrate including the wafer and the conductive film, or a substrate including the wafer, the insulating film, and the conductive film.

  Next, the exposed resist film is developed.

  Next, the substrate is etched using the resist film (resist pattern) remaining after development as a mask.

  When the base of the resist pattern is a wafer, for example, an element isolation groove is formed by the etching. When the base is an insulating film, for example, a connection hole is formed by the etching. When the base is a conductive film, for example, an electrode or a wiring is formed by the etching.

(Second Embodiment)
As device patterns become finer, there are cases where the obstacle graphic cannot be solved even if the above-described correction of the obstacle graphic is performed. Even in this case, as will be described below, the mask construction period can be shortened by devising the mask inspection in the mask manufacturing process.

  FIG. 15 is a flowchart showing a mask data generation method for carrying out the mask inspection method.

  First, a mask inspection sensitivity table as shown in FIG. 16 is prepared (step S21). The mask inspection sensitivity table is a table created in advance based on the test mask inspection results described in the first embodiment, or a table newly created when mask data is created.

  The column (horizontal axis) of this mask inspection sensitivity table shows dimension parameters that define the figure size of each evaluation pattern. Here, the dimension parameters are LS pitch, LS pattern width, space width, opposite side distance (Gx, Gy) between CH patterns, and inter-corner distance Gz between CH patterns. Furthermore, each dimensional parameter is classified by specific numerical values.

  On the other hand, the row (vertical axis) of the mask inspection sensitivity table indicates the film condition of the region where the pattern is formed (pattern formation region). Specifically, film conditions that include a light-shielding film on the glass substrate in the pattern formation region, film conditions that include a semi-transparent film on the glass substrate in the pattern formation region, and light shielding on the glass substrate in the pattern formation region The film condition includes a film and a translucent film on the light shielding film. Furthermore, it is classified into micro unevenness conditions 1, 2,. The micro unevenness condition is defined by the horizontal dimension x and the vertical dimension y of the micro unevenness as shown in FIG.

  In the pattern portion determined by the combination of the pattern category and the film condition, the mask inspection sensitivity that does not cause the above-described pseudo defect is defined. FIG. 18 shows a specific example of the mask inspection sensitivity table for the combination of the pattern category being LS pitch and the film condition being glass substrate / Cr light-shielding film (glass / Cr).

  Next, correction including OPC is performed on the design data of the pattern of the device formed on the wafer (step S22).

  Next, mask data is created as usual based on the post-OPC design data (step S23). The mask data created in this way is hereinafter referred to as normal mask data.

  Then, data including normal mask data and the mask inspection sensitivity table is created, and this data is used as mask data (step S24).

  Next, a mask manufacturing method using the mask data created in this way will be described.

  First, based on the normal mask data in the mask data, a mask is manufactured as described in the first embodiment.

  Next, the mask is inspected for defects using a mask inspection sensitivity table in the mask data. At this time, a pattern that matches the combination of the dimension parameter defined in the mask inspection sensitivity table and the film condition (micro unevenness condition) is detected, and the matching pattern is detected with the sensitivity defined in the mask inspection sensitivity table. Perform defect inspection. For non-matching patterns, defect inspection is performed with normal sensitivity (inspection sensitivity required for the mask or maximum sensitivity that can be inspected by a defect inspection apparatus).

  Specifically, first, the entire inspection area of the mask is inspected for defects with normal sensitivity. However, the area (specific definition area) that includes the pattern that matches the combination of the dimension parameter and film condition defined in the mask inspection sensitivity table is excluded from the inspection target, or the inspection result of the specific definition area is discarded. To do. Next, defect inspection is performed with a predetermined sensitivity defined in the mask inspection sensitivity table in the specific definition region.

  The masks that pass the inspection are shipped.

  FIG. 19 shows an example of a mask including a plurality of regions inspected with an inspection sensitivity different from the normal inspection sensitivity. FIG. 19 shows a first region 41 to be inspected with a first inspection sensitivity different from the normal inspection sensitivity, second regions 42a to 42d to be inspected with a second inspection sensitivity different from the normal inspection sensitivity, The third regions 43a-43d to be inspected with a third inspection sensitivity different from the inspection sensitivity are shown.

  The first region 41 is, for example, a DRAM region, and the film condition is, for example, a glass / translucent film. The second regions 42a to 42d are, for example, SRAM regions, and the film condition is, for example, a glass / translucent film. The film condition of the third regions 43a-43d is, for example, glass / semi-transparent film / Cr. Regions other than the first to third regions (regions without hatching) are regions that are inspected with normal inspection sensitivity.

  Thus, by manufacturing and inspecting the mask using the mask data including the normal mask data and the mask inspection sensitivity table, it is possible to cope with a useless pattern that cannot be resolved on the mask and cannot be corrected (or corrected). Even if there are figures on the mask data that are difficult to correct (or difficult to correct) and that correspond to patterns that are prone to false defects in the mask inspection system The pattern on the wafer corresponding to the figure is inspected with an appropriate inspection sensitivity. As a result, obstacles in mask production are reduced, and the mask construction period can be shortened.

  The manufacturing method of the semiconductor device of this embodiment is the same as the manufacturing method of the semiconductor device of the first embodiment, except that the mask obtained by the above method is used.

  The pattern data creation method of the embodiment described above can also be implemented as a program.

  That is, the program according to the pattern data creation method of the embodiment is for causing a computer to execute steps S11 to S15 (procedure). Alternatively, it is for causing the computer to execute steps S1-S6 and S11-S15.

  A program according to another pattern data creation method of the embodiment is for causing a computer to execute steps S21 to S24.

  The above program is executed using hard wafer resources such as a CPU and a memory in a computer (an external memory may be used in combination). The CPU reads necessary data from the memory and performs the above steps (procedures) on the data. The result of each step (procedure) is temporarily stored in the memory as necessary, and is read when needed in another step (procedure). Furthermore, the present invention can also be implemented as a recording medium on which the program is recorded.

  The above is summarized as follows.

(1) A mask data creation method includes a step of performing correction including optical proximity effect correction on design data of a pattern of a device formed on a wafer, and the design data subjected to the correction includes characteristics of the device. Although there is no influence on the mask, the step of determining whether or not the obstacle figure having a minute dimension that becomes an obstacle in manufacturing the mask is included, and if the corrected design data contains the obstacle figure, A step of correcting the obstruction graphic so as not to be an obstruction graphic having a minute dimension that hinders manufacture.

(2) A mask data creation method includes a step of performing correction including optical proximity effect correction on design data of a device pattern formed on a wafer, and the design data subjected to the correction includes the characteristics of the device. Although there is no influence, the step of determining whether or not including a failure graphic having a minute dimension that becomes an obstacle in mask manufacturing, and when the corrected mask data includes the failure graphic, Determining a mask inspection sensitivity at which a region on the mask corresponding to the obstacle graphic is not detected as a pseudo defect.

(3) In the above (2), the step of determining the mask inspection sensitivity is performed when the obstacle graphic cannot be corrected so as to be an obstacle graphic having a minute dimension which becomes an obstacle in manufacturing the mask.

(4) In any one of the above (1) to (3), the obstacle figure is a figure on the design data on the mask that has been subjected to the correction corresponding to an isolated pattern having a dimension that cannot be formed on the mask. The figure on the design data subjected to the correction corresponding to the isolated pattern having a dimension that cannot be formed with a predetermined dimensional accuracy on the mask, on the mask detected as a pseudo defect by the mask inspection apparatus The figure on the design data subjected to the correction corresponding to the isolated pattern, and the figure on the design data subjected to the correction corresponding to a pattern including two adjacent patterns having a distance that cannot be formed on the mask The design data subjected to the correction corresponding to the pattern including two adjacent patterns that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy on the mask. The figure on the design data corresponding to the pattern including two adjacent patterns on the mask having a distance detected as a pseudo defect by the mask inspection apparatus, and cannot be formed on the mask The figure on the design data subjected to the correction corresponding to the concave / convex pattern having a proper dimension, the convex / concave pattern corresponding to the concave / convex pattern having a dimension that can be formed on the mask but cannot be formed with a predetermined dimensional accuracy. It includes at least one of the figure on the design data subjected to the correction and the figure on the design data subjected to the correction corresponding to the concavo-convex pattern on the mask detected as a pseudo defect by the mask inspection apparatus.

(5) In any one of the above (1) to (4), in the step of determining whether or not the corrected design data includes the obstacle graphic, a plurality of shapes and dimensions of the obstacle graphic are registered. Based on the table.

(6) In any one of the above (1) to (5), is the table prepared in advance for each required specification accuracy of a mask to be created, or is prepared in advance for each mask manufacturing apparatus used at the time of mask creation? The mask is newly formed for each required specification accuracy of the mask to be created, or is newly formed for each mask manufacturing apparatus used at the time of mask creation.

(7) In any one of the above (1) to (6), the step of correcting the obstacle graphic includes the correction of deleting the obstacle graphic, or the shape of the obstacle graphic registered in the table. It includes correction to deform into a shape different from the shape.

(8) A mask manufacturing method is a method of creating mask data using the mask data creation method of any one of (1) to (7) above, and coating on a substrate including a transparent substrate based on the mask data. A step of exposing the exposed resist film, a step of developing the exposed resist film, and a step of etching the substrate using the resist film remaining after the development as a mask.

(9) A method for manufacturing a semiconductor device includes a step of exposing a resist film applied on a substrate including a wafer, a step of developing the exposed resist film, using the mask described in (1) above, Etching the substrate using the resist film remaining after the development as a mask.

(10) The program includes a procedure for performing correction including optical proximity effect correction on design data of a device pattern formed on a wafer, and the design data subjected to the correction includes characteristics of the device. Although there is no influence, the procedure for determining whether or not an obstacle figure having a minute dimension that becomes an obstacle in mask manufacturing is included, and if the corrected design data contains an obstacle figure, This is for causing the computer to execute a procedure for correcting the obstacle graphic so that the obstacle graphic has a small dimension that becomes an obstacle.

(11) The program includes a procedure for performing correction including optical proximity effect correction on design data of a device pattern formed on a wafer, and the design data subjected to the correction includes characteristics of the device. Although there is no influence, the procedure for determining whether or not an obstacle figure having a minute dimension that becomes an obstacle in mask manufacturing is included, and when the corrected design data includes an obstacle figure, the obstacle figure is determined. And a procedure for determining a mask inspection sensitivity in which a region on the mask corresponding to the above is not detected as a pseudo defect.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  In addition, various modifications can be made without departing from the scope of the present invention.

The flowchart which shows the mask rule table creation method of embodiment. The flowchart which shows the mask data creation method of embodiment. Sectional drawing which shows the micro unevenness | corrugation part of a test figure. The top view which shows the adjacent adjacent diagonal part of a test figure. The top view which shows the adjacent adjacent opposite side part of a test figure. The reverse pattern of FIG. The reverse pattern of FIG. The top view which shows the line pattern of an evaluation figure, the L & S pattern, and the inversion pattern of a line pattern. The top view which shows the isolated CH pattern and two-dimensional CH pattern of an evaluation figure. The block diagram which shows schematic structure of a mask defect inspection apparatus. Sectional drawing which shows the micro convex part (obstacle figure) detected based on the mask rule table. Sectional drawing which shows the result of having corrected the minute convex figure of FIG. The top view which shows the adjacent adjoining diagonal part (obstacle figure) detected based on the mask rule table. The figure for demonstrating the correction | amendment method of the adjacent adjacent diagonal part of FIG. The flowchart which shows the mask data creation method of embodiment. The figure for demonstrating a mask inspection sensitivity table. The figure for demonstrating micro unevenness | corrugation conditions. A specific example of a mask inspection sensitivity table is shown. The top view which shows the mask containing the several area | region test | inspected by the test | inspection sensitivity different from normal test | inspection sensitivity.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... XY table, 12 ... Mask, 13 ... Computer, 14 ... Stage control circuit, 15 ... Light source, 16 ... Imaging device, 17 ... AD converter, 18 ... Pattern development circuit, 19 ... Reference data generation circuit, 20 ... Comparison Circuit, 30 ... Design data after OPC, 31 ... Minute convex part, 32 ... Proximity adjacent diagonal part, 33, 34 ... Two adjacent figures.

Claims (5)

A step of performing correction including optical proximity correction on design data of a device pattern formed on a wafer;
Determining whether the design data subjected to the correction includes an obstruction figure having a minute dimension that does not affect the characteristics of the device but becomes an obstacle in manufacturing the mask;
A step of correcting the obstruction graphic so that the design data subjected to the correction includes an obstruction figure so as not to be an obstruction figure having a minute dimension that obstructs the mask manufacturing. To create mask data. A step of performing correction including optical proximity correction on design data of a device pattern formed on a wafer;
Determining whether the design data subjected to the correction includes an obstruction figure having a minute dimension that does not affect the characteristics of the device but becomes an obstacle in manufacturing the mask;
A step of determining a mask inspection sensitivity in which a region on the mask corresponding to the obstacle graphic is not detected as a pseudo defect when it is determined that the corrected mask data includes the obstacle graphic. Mask data creation method. The obstacle figure is
A figure on the design data subjected to the correction corresponding to an isolated pattern having a dimension that cannot be formed on the mask;
A figure on the design data subjected to the correction corresponding to an isolated pattern having a dimension that can be formed on the mask but cannot be formed on the mask with a predetermined dimensional accuracy;
The figure on the design data subjected to the correction corresponding to the isolated pattern on the mask detected as a pseudo defect by the mask inspection apparatus,
A figure on the design data subjected to the correction corresponding to a pattern including two adjacent patterns having a distance that cannot be formed on the mask;
A figure on the design data subjected to the correction corresponding to a pattern including two adjacent patterns that can be formed on the mask but cannot be formed on the mask with a predetermined dimensional accuracy;
A figure on the design data subjected to the correction corresponding to a pattern including two adjacent patterns on the mask having a distance detected as a pseudo defect by the mask inspection apparatus,
A figure on the design data subjected to the correction corresponding to the uneven pattern having a dimension that cannot be formed on the mask;
A figure on the design data subjected to the correction corresponding to the concavo-convex pattern having a dimension that can be formed on the mask but cannot be formed on the mask with a predetermined dimensional accuracy,
and,
3. The mask data according to claim 1, comprising at least one figure on the design data subjected to the correction corresponding to the uneven pattern on the mask detected as a pseudo defect by the mask inspection apparatus. How to make. Creating mask data using the mask data creating method according to any one of claims 1 to 3,
A step of exposing a resist film applied on a substrate including a transparent substrate based on the mask data;
Developing the exposed resist film;
And a step of etching the substrate using the resist film remaining after the development as a mask. Using the mask according to claim 4, exposing a resist film applied on a substrate including a wafer;
Developing the exposed resist film;
And a step of etching the substrate using the resist film remaining after the development as a mask.

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