JP6797627B2 - Imprinting equipment, imprinting methods, and manufacturing methods for articles - Google Patents

Description

The present invention relates to an imprinting apparatus, an imprinting method, and a method of manufacturing an article.

An imprint device is known as a device for forming a fine pattern on a substrate for manufacturing a semiconductor device or the like. The imprint device is a device that forms a pattern of a cured product to which the uneven pattern of the mold is transferred by bringing the imprint material supplied on the substrate into contact with the mold and giving energy for curing to the imprint material. is there.

Patent Document 1 discloses an imprint device that locally thermally deforms the area to be processed by irradiating the area to be processed, which is the area where the base pattern of the substrate is formed. By reducing the shape difference between the region where the uneven pattern of the mold is formed and the region to be treated, the accuracy of superimposing the base pattern and the pattern of the cured imprint material formed on the region to be treated is improved. The purpose is.

Japanese Patent Application Laid-Open No. 2013-102132

The imprinting apparatus described in Patent Document 1 is processed based on the irradiation dose distribution data generated based on the preset light absorption coefficient of the area to be processed, the coefficient of thermal expansion of the material, and the shape of the area to be processed. The area is illuminated with light. However, if the light absorption rate is different from the predicted value depending on the combination of the materials of each layer laminated on the substrate and the density of the pattern to be formed, it may be difficult to deform the area to be processed as expected.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an imprinting apparatus, an imprinting method, and an article manufacturing method capable of accurately correcting the shape of an irradiated area.

The present invention is an imprinting apparatus that forms a pattern of an imprint material on a substrate using a mold, and comprises a heating means for irradiating a processed region on the substrate with light to heat the processed region. A means for creating irradiation amount distribution data showing an irradiation amount distribution of light to be irradiated to the area to be treated by the heating means, a measuring means for measuring information on absorption of the light in the area to be treated, and a measuring means. The preparation means corrects the provisional irradiation amount distribution data tentatively created based on the shape of the area to be processed before being heated by the heating means by using the measurement result of the measurement means. It is characterized in that the irradiation dose distribution data is created.

According to the present invention, the shape of the irradiated area can be corrected with high accuracy.

It is a figure which shows the structure of the imprint apparatus which concerns on 1st Embodiment. It is a figure which shows the structure of the measuring part which concerns on 1st Embodiment. It is a figure which shows the relationship between the reflectance information and a correction coefficient. It is a flowchart which shows the imprint method which concerns on 1st Embodiment. It is a figure explaining the calorific value distribution used in the 2nd Embodiment. It is a figure which shows the structure of the imprint apparatus which concerns on 4th Embodiment. It is a flowchart which shows the measurement method concerning 4th Embodiment. It is a figure which shows the structure of the imprint apparatus which concerns on 5th Embodiment. It is a flowchart which shows the imprint method which concerns on 5th Embodiment.

[First Embodiment]
(Device configuration)
FIG. 1 is a diagram showing a configuration of an imprint device 100 according to the first to third embodiments. In FIG. 1, the vertical direction is the Z axis, and the two axes orthogonal to each other in the plane perpendicular to the Z axis are the X axis and the Y axis. The imprint device 100 cures the imprint material 20 in a state where the photocurable imprint material 20 supplied to the processed region (processed region 11) 11 on the substrate 10 is in contact with the mold 30. The pattern of the imprint material 20 is formed on the area 11 to be processed. Glass, ceramics, metal, semiconductors, resins and the like are used for the substrate 10, and if necessary, a member made of a material different from the substrate 10 may be formed on the surface thereof. The substrate 10 is, for example, a silicon wafer, a compound semiconductor wafer, quartz glass, or the like.

The imprinting apparatus 100 includes an irradiation unit 40, a mold stage 31, a substrate stage 12, and a supply unit 50 as a forming means for forming a pattern of the imprint material 20 on the region 11 to be processed.

The irradiation unit 40 irradiates the substrate 10 with ultraviolet rays 41 for curing the uncured imprint material 20.

The mold 30 has a rectangular outer circumference, and has a rectangular mold-side pattern (mold pattern region) 30a in which an uneven pattern is formed at the center thereof. The mold side pattern 30a has substantially the same size as the area to be processed 11. One transfer pattern of the mold side pattern 30a is formed on one processed area 11 by one operation of bringing the imprint material 20 into contact with the mold 30 (molding operation) and a pulling operation (release operation). ..

In the present embodiment, the area to be processed 11 has the same size as the shot area. The shot region is a unit region of the base pattern already formed on the substrate 10, and the size of one shot region is, for example, about 26 × 33 mm. One or more chip regions having a chip size desired by the user are formed in one shot region.

When the imprint material 20 is photocurable, the mold 30 is a material that transmits ultraviolet rays 41 and heating light (heating light) 62 emitted from a heating mechanism 60 described later. For example, in addition to glasses such as quartz glass, silicic acid glass, calcium fluoride, magnesium fluoride, and acrylic glass, imprint materials such as sapphire, gallium nitride, polycarbonate, polystyrene, acrylic, and polypropylene are used. Alternatively, any of these laminated materials may be used.

The mold stage 31 moves the mold 30 along the Z-axis direction while holding the mold 30 by a vacuum suction force or an electrostatic force. The mold stage 31 has an opening region 32 in the center so that the ultraviolet rays 41 reach the substrate 10. The mold 30 is moved during the stamping operation and the operation of pulling the imprint material 20 and the mold 30 apart (release operation).

The deformation mechanism 23 deforms the mold 30 into a desired shape by applying an external force to the mold 30 in the horizontal direction. As a result, the difference between the shape of the area to be processed 11 and the shape of the mold side pattern 30a is reduced.

The substrate stage 12 moves in the XY plane while holding the substrate 10 by a vacuum suction force or an electrostatic force. For example, when forming the pattern in the area to be processed 11, the substrate 10 is moved between the position below the supply unit 50 and the position below the mold stage 31, which will be described later.

The drive mechanism (not shown) for moving the mold stage 31 and the substrate stage 12 may be composed of a plurality of drive systems such as a coarse movement drive system and a fine movement drive system. Further, the mold stage 31 may include a drive mechanism not only in the Z-axis direction but also in the X-axis direction, the Y-axis direction, and the rotation direction around each axis. The substrate stage 12 may include a drive mechanism not only in the X-axis direction and the Y-axis direction, but also in other axial directions and in the rotation direction around each axis.

The stamping operation and the mold release operation may be performed by moving at least one of the mold stage 31 and the substrate stage 12 in the Z-axis direction. As the drive mechanism described above, for example, a linear motor or a piezo actuator may be used.

The supply unit 50 supplies the imprint material 20 in an uncured state onto the area 11 to be treated. The supply unit 50 can adjust the arrangement and amount of the imprint material 20. The arrangement and amount of the imprint material 20 are adjusted according to the density of the uneven pattern formed on the mold side pattern 30a and the like.

The heating mechanism (heating means) 60 irradiates the light 62 to heat the region 11 to be treated. As a result, the area to be processed 11 is deformed into the target shape. The heating mechanism 60 corrects the shape of the region 11 to be treated, thereby reducing the shape difference between the region 11 to be treated and the mold side pattern 30a.

The heating mechanism 60 includes a light source 61, a regulator 63 that adjusts the illuminance distribution and irradiation time zone of the light 62 emitted from the light source, and a mirror 64 that deflects the light from the regulator 63 toward the substrate 10. Have. Further, a condensing optical system (not shown) that condenses the light emitted from the light source 61, and a uniform illumination optical system (not shown) for equalizing the intensity of the light from the condensing optical system to illuminate the regulator 63. (Shown). The uniform illumination optical system has an optical element such as a microlens array (not shown).

The light 62 has a wavelength at which the imprint material 20 does not cure. For example, it is preferable that the light has a wavelength different from the wavelength of ultraviolet 41 and exists in the wavelength band of 400 to 1200 nm. In particular, it is preferable that the light has a wavelength band that is hardly absorbed by the mold 30 and is easily absorbed on the substrate 10. When there is light used in the imprinting apparatus 100 in addition to the ultraviolet 41, it is preferable that the light has a wavelength other than the wavelength band of the light. Alternatively, light in a wavelength band of 200 to 400 nm may be used as long as the imprint material 20 is light in a wavelength band that is difficult to be exposed to.

As the regulator 63, for example, a DMD (Digital Micro-millor Device) is used. The DMD has a plurality of micromirrors (not shown) that reflect light, and each micromirror is tilted at an angle of -12 degrees (ON state) or +12 degrees (OFF state) with respect to the array surface of the micromirrors. Therefore, the presence or absence of irradiation of the light 62 is selected. The size of the irradiation area of the light 62 in the ON state from all the micromirrors is the same size as the ideal size of the area to be processed 11.

The irradiation control unit 65 has a CPU and selectively controls switching between the ON state and the OFF state of each micromirror based on the irradiation amount distribution data instructed from the control unit 90 described later.

The irradiation amount distribution data includes information on the length (timing) of irradiating the processed region 11 with light from each micromirror in the ON state and information on the illuminance distribution in the processed region 11 formed at the same time. And include.

The more the number of micromirrors in the ON state and the longer the irradiation time of the light 62, the larger the irradiation amount to the area to be processed 11. That is, the amount of heat applied to the area to be processed 11 increases. The heating mechanism 60 may change the irradiation amount by changing the intensity of the light 62 instead of adjusting the irradiation amount by changing the irradiation time.

By imparting the irradiation amount distribution by the heating mechanism 60, the heat amount distribution is formed in one area to be treated 11. In this way, the area to be processed 11 is locally deformed into a desired shape.

The irradiation control unit 65 further controls the timing of emitting the light 62. As the regulator 63, a liquid crystal device capable of changing the irradiation amount distribution by individually controlling the voltages for the plurality of liquid crystal elements may be used.

The mirror 64 is also arranged on the optical path of the ultraviolet ray 41. The mirror 64 is, for example, a dichroic mirror that transmits ultraviolet rays 41 and reflects light 62.

In the present embodiment, the measuring unit 70 is a means for acquiring information regarding the absorption of the light 62 (heating light) of the region 11 to be processed. Further, the information regarding the absorption of the light 62 is the reflectance of the light 62 in the region 11 to be processed. The measuring unit 70 measures the reflectance of the region 11 to be processed by receiving the light 62 reflected by the region 11 to be processed.

FIG. 2 is a diagram showing the configuration of the measuring unit 70. The measuring unit 70 has an optical system 75 including a light emitting unit 72 that projects the measurement light 71 onto the area to be processed 11 and a light receiving unit 74 that receives the reflected light 73 reflected by the area 11 to be processed. Further, the light receiving unit 74 has a calculation unit 76 that calculates the reflectance in the area to be processed 11 based on the result of receiving light.

The wavelength band of the measurement light 71 used by the measurement unit 70 for measurement preferably includes at least the wavelength band of the light 62 used by the heating mechanism 60 for heating. When the wavelength band of the measurement light 71 is sufficiently wider than the wavelength band of the light 62 (for example, when white light is used), the reflectance corresponding to each wavelength included in the wavelength band of the light 62 is calculated. do it. If the reflectance value varies depending on the wavelength, an averaging process may be performed.

The calculation unit 76 calculates the reflectance of the area to be processed 11 from the intensity ratio of the reflected light 73 to the measurement light 71. The reflectance of the processed region 11 measured by the measuring unit 70 is the reflectance of the material layer constituting the surface side of the processed region 11. The reflectance calculated by the calculation unit 76 is stored in the storage unit 92 by the control unit 90.

The observation unit 80 observes the mark 81 formed on the mold side pattern 30a and the mark 82 formed on the area to be processed 11. The marks 81 are arranged at at least four corners of the mold side pattern 30a, and the marks 82 are arranged at at least four corners of the area to be processed 11. Based on the observation result by the observation unit 80, the control unit 90, which will be described later, obtains the shape of the mold-side pattern 30a and the processed region 11, and obtains the relative positional deviation of the processed region 11 with respect to the mold-side pattern 30a.

The control unit 90 has a CPU, RAM, and ROM, and is connected to the control unit 90. The substrate stage 12, the mold stage 31, the irradiation unit 40, the supply unit 50, the irradiation control unit 65, the measurement unit 70, and the observation unit. The 80 and the storage unit 92 are collectively controlled. It has a function of executing the imprint process according to the program shown in the flowchart of FIG. 4 described later.

The control unit 90 obtains the shape of the mold side pattern 30a and the area to be processed 11 based on the observation results of the marks 81 and 82 by the observation unit 80. Further, the shape correction amount of the mold side pattern 30a and the shape correction amount of the processed region 11 are calculated from the shape difference between the mold side pattern 30a and the processed region 11.

Further, the control unit 90 has a function as a creating means, and creates irradiation amount distribution data showing the irradiation amount distribution of the light 62 that the heating mechanism 60 irradiates the processed region 11. At this time, the irradiation amount distribution data is created by correcting the provisional irradiation amount distribution data temporarily created based on the shape of the area to be processed 11 before being heated by the heating mechanism 60 by using the measurement result by the measurement unit 70. ..

The temporary irradiation amount distribution data is data theoretically calculated based on the absorption rate of light 62, the coefficient of thermal expansion, etc., which is calculated from the shape of the region 11 to be processed, the structure of the substrate 10, and the physical property values of the constituent materials. is there. The method of creating the irradiation dose distribution data will be described in detail later. The control unit 90 determines a correction coefficient (correction value) required for correction based on the measurement result by the measurement unit 70.

The irradiation amount distribution data created by the control unit 90 is irradiation amount distribution data that reduces the shape difference between the mold side pattern 30a and the area to be processed 11.

The storage unit 92 is composed of a hard disk (storage medium) or the like that can be read by the control unit 90. The storage unit 92 stores the reflectance (A1, A2, ... An) and the correction coefficient (α1, α2, ... αn) in association with each other as shown in FIG.

Since the light that is not absorbed in the area 11 to be processed is reflected, the reflectance has a correlation with the absorption rate. For example, it is obtained by absorption rate = 1- (reflectance). Therefore, the correction coefficient is determined based on the absorption rate I of the light 62 in the processed region 11 used for creating the provisional irradiation amount distribution data and the reflectance measured by the measuring unit 70, and the light in the processed region 11 is determined. The ratio I / I'of the reflectance I'of (heating light) 62. Alternatively, it may be the difference between the absorption rate of the light 62 stored in advance in the storage unit 92 as a design value and the absorption rate calculated by the control unit 90 from the reflectance measured by the measuring unit 70. Instead of the correspondence table (table) as shown in FIG. 3, a function showing the relationship between the reflectance and the correction coefficient may be stored.

Further, the storage unit 92 stores the program shown in the flowchart of FIG.

(Imprint method)
FIG. 4 is a flowchart showing an imprint method according to the present embodiment. Based on the instruction from the control unit 90, each component connected to the control unit 90 performs the following operations. In the present embodiment, the reflectance measured at one location is also applied to the region to be processed 11 including the measurement location and the other region to be processed 11 on the same substrate as the substrate 10 having the measured region 11 to be processed. Same reflectance and same.

The measuring unit 70 measures the reflectance of the area 11 to be processed in a state where the area 11 to be processed is positioned below the measuring unit 70 (S101). The reflectance obtained by the measurement is stored in the storage unit 92 by the control unit 90.

The supply unit 50 supplies the imprint material 20 onto the area to be processed 11 (S102). The substrate stage 12 positions the area to be processed 11 below the mold 30. Then, based on the observation result of the mark 81 and the mark 82 by the observation unit 80, the control unit 90 obtains the shape difference between the shape of the mold side pattern 30a and the shape of the area to be processed 11 (S103). The shape difference between the shape of the mold-side pattern 30a and the area to be processed 11 may be obtained in advance outside the imprinting apparatus 100. For example, it may be the difference between the shape of the area to be processed 11 measured externally and the shape of the mold side pattern 30a obtained based on the design value of the mold side pattern 30a.

The control unit 90 calculates the shape correction amount of the mold side pattern 30a by the deformation mechanism 23 and the shape correction amount of the processed region 11 by the heating mechanism 60 from the shape difference between the mold side pattern 30a and the processed region 11. S104). At this time, the shape of the mold-side pattern 30a after correction and the shape of the area to be processed 11 after correction match, or the shape difference between the shape of the mold-side pattern 30a after correction and the area to be processed 11 after correction is reduced. As described above, each shape correction amount is calculated.

When the deformation mechanism 23 applies an external force to the mold side pattern 30a, the mold 30 is deformed in the direction in which the force is applied, and stress is generated in the direction perpendicular to the direction in which the external force is applied according to the Poisson's ratio. The shape correction amount of the region 11 to be processed is preferably determined in consideration of the deformation of the mold side pattern 30a generated according to the Poisson's ratio. In this case, it is possible to reduce the higher-order component of the shape difference between the mold side pattern 30a and the area to be processed 11 as compared with the case where the shape is corrected only by the deformation mechanism 23.

The control unit 90 uses information such as the shape correction amount of the area to be processed 11 calculated in S104, the absorption rate of the material of the area 11 to be processed, the coefficient of thermal expansion, and the like, and temporarily irradiates the heat amount to be applied by the heating mechanism 60. Quantitative distribution data F (x, y, t) is created (S105).

The control unit 90 reads out the reflectance stored in the storage unit 92, and determines the correction coefficient used for correcting the provisional irradiation amount distribution data while referring to the relationship between the reflectance and the correction coefficient (S106). The correction coefficient may be determined at any timing from S101 to before S106.

The control unit 90 performs arithmetic processing including an operation of multiplying the provisional irradiation amount distribution data F (x, y, t) by the correction coefficient α determined in S105, and performs the irradiation amount distribution data F'(x, y, y). , T) is created (S107). For example, it is created by calculating F'= α × F. Before and after performing the calculation of multiplying the provisional irradiation dose distribution data F (x, y, t) by the correction coefficient, other calculation processing such as subtracting a predetermined number as an offset or multiplying by a predetermined number is performed. May be good.

The heating mechanism 60 heats the area to be treated 11 based on the corrected irradiation amount distribution obtained in S107. As a result, the area to be processed 11 is stretched in a predetermined direction, and the shape is corrected (S108). Even when the light is absorbed only on the surface side of the region 11 to be treated, the heat generated there is also transferred to the substrate 10, and as a result, the light is stretched together with the substrate 10.

The deformation mechanism 23 applies an external force to the mold 30 based on the shape correction amount of the mold 30 obtained in S104. As a result, the shape of the mold side pattern 30a is corrected to a desired shape (S109). By the steps of S108 and S109, the difference between the shape of the mold side pattern 30a and the shape of the area to be processed 11 is reduced as compared with the step of S103. Either of the steps S108 and S109 may be performed first.

As a stamping operation, the mold stage 31 lowers the mold 30 to bring the mold 30 into contact with the imprint material 20 (S110). The imprinting operation of S110 may be performed before at least one of the steps of S108 and S109. The recess of the mold side pattern 30a is filled with the imprint material 20.

The irradiation unit 40 is in a state in which the heating mechanism 60 irradiates the area to be processed 11 with light 62 based on the irradiation amount distribution data to thermally deform the area 11 to be processed, and the imprint material 20 and the mold 30 are in contact with each other. Then, the ultraviolet rays 41 are irradiated. As a result, the imprint material 20 is cured (S111). After curing, as a mold release operation, the mold stage 31 raises the mold 30 and separates the mold 30 from the imprint material 20 (S112). As a result, a pattern of the three-dimensional imprint material 20 that follows the uneven portion of the mold side pattern 30a is formed on the area to be processed 11.

The control unit 90 determines whether or not there is a processed region 11 to be molded next (S112), and if it is determined that there is no (No), the control unit 90 terminates this program and carries out the unloading process of the substrate 10. If it is determined in S112 that there is (Yes), S102 to S112 are repeated. The control unit 90 uses the reflectance measured in S101 as the reflectance of the new area to be processed 11.

The above-mentioned imprint processing may be performed only on the first substrate to be processed in the same lot. In this case, the subsequent substrate 10 in the same lot is imprinted by omitting the reflectance measurement step in S101. The measuring unit 70 may measure the reflectance each time a new material layer is laminated.

In this way, the control unit 90 corrects the provisional irradiation amount distribution data based on the measurement result by the measurement unit 70, thereby creating the irradiation amount distribution data used by the heating mechanism 60 for heating the area 11 to be processed. Even if the absorption rate of the light 62 in the area to be processed 11 assumed at the time of calculating the temporary irradiation amount distribution data and the actual absorption rate of the light 62 are different, the combination of materials and the pattern density of the base pattern of the substrate 10 can be used. Regardless, the effect of the absorption rate error can be corrected. As a result, the shape of the area to be processed 11 can be corrected with high accuracy, and a pattern by imprint processing can be formed with high overlay accuracy.

[Second Embodiment]
In the present embodiment, the measuring unit 70 is the means for acquiring the information regarding the absorption of the light 62 in the area 11 to be processed. Further, the information regarding the absorption of the light 62 is the reflectance of the light 62 in the region 11 to be processed.

The reflectance depends on the density of the circuit pattern formed in the region 11 to be processed. For example, the reflectance may be high in a place where the pattern density is high, and the reflectance may be low in a place where the pattern density is low. In the present embodiment, the creating means measures the reflectance at each of the plurality of locations by receiving the reflected light 73 reflected by the measuring unit 70 at the plurality of locations within one chip region 95. The control unit 90 corrects the provisional irradiation distribution data based on the measurement results in each of the processed regions 11 of the measurement unit 70, and creates the irradiation amount distribution data.

FIG. 5 is a diagram showing one processed region 11 and four chip regions (plurality of chip regions) 95 included in the processed region 11.

The imprint method of this embodiment is almost the same as that of the first embodiment. In S101 of the flowchart of FIG. 4, the measuring unit 70 measures the reflectance at a plurality of locations within at least one chip region 95. For example, the reflectance is measured in each of the regions 95a, 95b, 95c, and 95d, which are the division regions in which the chip region 95 is virtually divided.

The control unit 90 obtains a total of four correction coefficients α1, α2, α3, and α4 corresponding to the respective regions of the regions 95a, 95b, 95c, and 95d based on the measurement results of the measurement unit 70. The provisional irradiation dose distribution data in each of the regions 95a, 95b, 95c, and 95d is corrected using the correction coefficients α1, α2, α3, and α4.

In this way, the control unit 90 corrects the provisional irradiation amount distribution data based on the measurement result by the measurement unit 70, so that the heating mechanism 60 uses the irradiation amount distribution data for heating the area to be processed 11. create. As a result, the shape of the area to be processed 11 can be corrected with high accuracy as in the first embodiment. Further, since the irradiation amount distribution data is created by using the information of the reflectance different depending on the difference in the pattern density in the chip region 95, the superposition accuracy can be improved as compared with the first embodiment.

The reflectance may be measured at more points in the chip region 95, the reflectance distribution function may be obtained, and the irradiation dose distribution may be determined based on the reflectance distribution function.

[Third Embodiment]
In the present embodiment, the measuring unit 70 is the means for acquiring the information regarding the absorption of the light 62 in the area 11 to be processed. Further, the information regarding the absorption of the light 62 is the reflectance of the light 62 in the region 11 to be processed.

Even within the plane of the same substrate 10, the surface state of the area to be processed 11 differs for each area 11 to be processed, and the light absorption rate also varies. In this embodiment, in view of the variation in the in-plane reflectance of the same substrate 10, the measuring unit 70 receives the light reflected by each of the plurality of processed regions 11 to receive the light reflected by each of the plurality of processed regions 11, respectively. Measure the reflectance at. The control unit 90 creates irradiation dose distribution data based on the measurement results of the measurement unit 70 in each area to be processed 11.

That is, the control unit 90 determines a correction coefficient corresponding to each processed region 11 whose reflectance has been measured, and corrects the provisional irradiation distribution data using the correction coefficient for each processed region 11. Create irradiation dose distribution data.

In the step of S101, the reflectance may be measured only in a plurality of typical areas to be processed 11 which are typical of the substrate 10. The control unit 90 performs an operation to supplement the reflectance at other points in the plane of the substrate 10 from the measurement result of the reflectance in the typical processed region 11, and distributes the reflectance in the plane of the substrate 10. By calculating, the reflectance at points other than the measurement point can also be calculated. As a result, the measurement time and the reciprocating drive time of the substrate stage 12 between the imprint position below the mold 30 and the measurement position by the measurement unit 70 are longer than when measuring the reflectance of all the areas to be processed 11. It can be shortened.

In this way, the control unit 90 corrects the provisional irradiation amount distribution data based on the measurement result by the measurement unit 70, thereby creating the irradiation amount distribution data used by the heating mechanism 60 for heating the area 11 to be processed. As a result, the shape of the area to be processed 11 can be corrected with high accuracy as in the first embodiment. Further, even when the light absorption rates are different in each of the plurality of processed regions 11, the shape of each processed region 11 can be corrected with high accuracy.

[Fourth Embodiment]
FIG. 6 is a diagram showing the configuration of the imprinting apparatus 200 according to the fourth embodiment, and the means for acquiring the information regarding the absorption of the light 62 in the area 11 to be processed is the spread camera 210. Further, the information regarding the absorption of the light 62 is the reflectance of the light 62 in the region 11 to be processed.

The spread camera 210 is a camera that observes the contact state between the imprint material 20 and the mold 30 supplied to the area to be processed 11 on the substrate 10. By observing the contact state between the mold 30 and the substrate 10 via the imprint material 20, the defective portion due to particles or unfilled is identified. The spread camera 210 includes a light source, an image sensor, an optical system, and a processing unit (all not shown). As the light source of the spread camera 210, an LED or the like that emits light 220 having a wavelength that the imprint material 20 does not sensitize is used, and a two-dimensional sensor such as a CCD sensor is used as the image sensor. The optical system includes an illumination optical system that uniformly illuminates the area including the area to be processed 11 of the substrate 10 with the light 220 from the light source, and an imaging optical system that optically couples the substrate 10 and the image sensor. including. The light 220 emitted from the light source passes through the mirror 230 and the mirror 64 arranged on the optical path of the ultraviolet ray 41, passes through the mold 30, and illuminates the area to be processed 11. The wavelength band of light 220 includes the wavelength of light 62.

The processing unit of the spread camera 210 processes the image obtained by the image sensor to calculate the reflectance of the area to be processed 11 with respect to the light 220. Further, the image obtained by the image sensor is processed to detect the sandwiching of particles between the imprint material 20 and the mold side pattern 30a and the unfilled defect of the imprint material in the mold side pattern 30a.

The mirror 230 reflects ultraviolet rays 41 toward the area to be processed 11 and transmits light 220. As the mirror 230, for example, a dichroic mirror is used.

In the imprint device 200, the same members as those of the imprint device 100 are designated by the same reference numerals. A detailed description of the components common to the imprint device 100 will be omitted.

The imprint method according to the present embodiment is different from the first embodiment in the method of measuring the reflectance and the method of determining the correction coefficient. A step performed instead of S101 in FIG. 4 will be described with reference to a flowchart showing a method for measuring the reflectance in FIG. 7. According to the program shown in the flowchart, the control unit 90 causes each component member to perform the following operations.

The storage unit 92 stores the reflected light intensity distribution of a bare wafer (a substrate on which a material layer is not formed, a calibration substrate) having a known reflectance, which is measured in advance by a spread camera, for calibration. The reflected light intensity distribution for calibration is an intensity distribution obtained from the reflected light when the image sensor of the spread camera 210 irradiates the area 11 to be processed with light 62 with a uniform illuminance distribution.

First, the supply unit 50 supplies the imprint material 20 onto the area to be processed 11 (S201). As a die stamping operation, the die stage 31 lowers the die 30 to bring the die 30 into contact with the imprint material 20 (S202).

The heating mechanism 60 is controlled to irradiate the area 11 to be treated with light 62 with a uniform illuminance distribution. The reflected light intensity distribution from the area to be processed 11 is measured by the spread camera 210 (S203). The control unit 90 converts the reflected light intensity distribution obtained in S203 from the reflected light intensity distribution for calibration stored in the storage unit 92 into a reflectance, and calculates the reflectance based on the measured value. It is stored in the storage unit 92 (S204). In addition to the reflected light intensity distribution for calibration in S204, the known reflectance of the calibration substrate may be used.

The irradiation unit 40 irradiates the area 11 to be treated with ultraviolet rays 41 to cure the imprint material 20 (S205). After curing, the mold stage 31 raises the mold 30 to perform a mold release operation (S206). This completes the program of the flowchart of FIG. 7.

Using the reflectance obtained by this program, the above-mentioned S102 to S113 are executed for the processed regions other than the processed region 11 used in S201 to S206. That is, the provisional irradiation amount distribution data is corrected by the correction coefficient obtained from the reflectance, which is information on the absorption of light in the processed region 11 measured by the spread camera 210, so that the processed region 11 is thermally deformed. Determine the dose distribution data.

As a result, in the imprint processing of S102 to S113, the shape of the area to be processed 11 can be accurately corrected regardless of the material layer laminated on the substrate 10 and the pattern already formed on the material layer. It is possible to improve the overlay accuracy in the processed region 11 where the pattern is formed in S102 to S113. Further, by measuring the reflectance using the same conditions as S108, that is, the light transmitted through the mold 30 and the imprint material 20, the reflectance information including the influence of the transmittance of the light 62 of the imprint material 20 is included. Can be measured. As a result, the overlay accuracy can be improved as compared with the first embodiment.

The control unit 90 may perform the process of S204 in parallel with the process of S205 and 206. Alternatively, it may be performed in parallel with the steps S102 to 105 that are continuously performed in the measurement method.

In the steps S102 to S113, the processing unit of the spread camera 210 confirms the presence or absence of defects such as particle pinching and non-filling of the imprint material in the mold side pattern 30a based on the light receiving result by the image sensor of the spread camera 210. You may. Further, if there is a defect, the information may be stored in the storage unit 92 via the control unit 90.

The measurement of the reflected light intensity distribution for calibration may be obtained with respect to the light emitted from the light source of the spread camera 210. Further, the reflected light intensity distribution obtained by irradiating with the provisional irradiation distribution data instead of the light having uniform illuminance at the time of the reflected light intensity distribution for calibration and the step of s103 may be used.

As a modification of the present embodiment, the information regarding the absorption of the light 62 may be the reflected light intensity obtained by using the spread camera 210, and in this case, the light intensity 41 is measured with the calibration substrate without obtaining the reflectance. The provisional irradiation amount distribution data may be corrected by using the ratio of the reflected light intensity to the target substrate. Alternatively, the information regarding the absorption of the light 62 may be the absorption rate of the ultraviolet ray 41 obtained from the reflected light intensity obtained by using the spread camera 210.

[Fifth Embodiment]
FIG. 8 is a diagram showing the configuration of the imprinting apparatus 300 according to the fifth embodiment, and the means for acquiring the information regarding the absorption of the light 62 in the area 11 to be processed is the infrared camera 210. Further, the information regarding the absorption of the light 62 is infrared rays (synchrotron radiation) from the area to be processed 11.

The infrared camera 310 includes a detector for detecting infrared light, an optical system, and a processing unit (all not shown) for processing the detection result. The detector of the infrared camera 310 is an infrared sensor in which a plurality of elements sensitive to infrared rays are arranged two-dimensionally. The optical system of the infrared camera 310 is an imaging optical system that optically conjugates the substrate 10 and the detector. The infrared camera 310 detects infrared light (synchrotron radiation) emitted from the area to be processed 11 heated by the heating mechanism 60. The processing unit of the infrared camera 310 obtains the temperature distribution based on the detection result of the detector and calculates the correction coefficient of the provisional irradiation amount distribution data.

The mirror 330 reflects ultraviolet rays 41 and transmits light 220. As the mirror 330, for example, a dichroic mirror is used.

In the imprint device 300, the same members as those of the imprint device 100 are designated by the same reference numerals. A detailed description of the components common to the imprint device 100 will be omitted.

FIG. 9 is a flowchart showing an imprint method according to the present embodiment. Based on the instruction from the control unit 90 made according to the program shown in the flowchart, each member performs the following operations.

The supply unit 50 supplies the imprint material 20 onto the area to be processed 11 (S301). As a die stamping operation, the die stage 31 lowers the die 30 to bring the die 30 into contact with the imprint material 20 (S302).

Subsequently, the observation unit 80 measures the shape of the area to be processed 11 by observing the mark 81 and the mark 82 (S303). From the shape difference between the mold side pattern 30a and the processed region 11, the control unit 90 calculates the shape correction amount of the mold side pattern 23 by the deformation mechanism 23 and the shape correction amount of the processed region 11 by the heating mechanism 60, respectively (S304). ..

Temporary irradiation amount distribution to be applied by the heating mechanism 60 using information such as the shape correction amount of the area to be processed 11 calculated in S304, the absorption rate of the material of the area 11 to be processed in design, and the coefficient of thermal expansion. Create data (S305). Further, the temperature distribution when the light 62 is irradiated to the area to be processed 11 is calculated based on the temporary irradiation amount distribution data, and is stored in the storage unit 92 in association with the temporary irradiation amount distribution.

The deformation mechanism 23 applies an external force to the mold 30 based on the shape correction amount of the mold 30 obtained in S304 to correct the shape to a desired shape (S306).

Based on the provisional irradiation amount distribution data obtained in S305, the heating mechanism 60 irradiates the processed region 11 with light 62 to correct the shape of the processed region 11 (S307).

The infrared light emitted from the area 11 to be processed due to the temperature rise of the area 11 to be processed by S307 is measured by the infrared camera 310 (S308).

The control unit 90 measures the temperature distribution of the area to be processed 11 in S308 based on the relationship between the temporary irradiation amount distribution data stored in the storage unit 92 in S305 and the temperature distribution (emissivity distribution), and obtains a desired temperature distribution. Is determined (S309). If it is determined that the desired temperature distribution is not achieved (NO), the process returns to S305, and the provisional irradiation dose distribution data is corrected using the emissivity as a correction coefficient so as to obtain the desired temperature distribution, and the irradiation dose distribution data is created. (S309a) The deformation mechanism 23, the heating mechanism 60, and the infrared camera 310 repeat S305 to S309 until it is determined in S309 that the temperature distribution is desired (YES). If it is determined in S309 that the temperature distribution is desired (YES), the process proceeds to S310.

The irradiation unit 40 irradiates the substrate 10 with ultraviolet rays 41 to cure the imprint material 20 (S310). After curing, as a mold release operation, the mold stage 31 raises the mold 30 and separates the mold 30 from the imprint material 20 (S311). As a result, a pattern of the three-dimensional imprint material 20 that follows the uneven portion of the mold side pattern 30a is molded on the surface of the area to be processed 11.

The control unit 90 determines whether or not there is a region to be processed 11 to be molded next (S312), and if it is determined that there is no region 11 to be processed (No), the control unit 90 ends this program and carries out the removal process of the substrate 10. If it is determined in S312 that there is (Yes), S301 to S312 are repeated.

By correcting the provisional irradiation amount distribution data using the result of receiving the infrared rays emitted from the area 11 to be processed by the infrared camera 230, the material layer laminated on the substrate 10 and the pattern already formed on the material layer are relied on. The shape of the area to be processed 11 can be corrected with high accuracy. Further, the overlay accuracy in the area to be processed 11 where the pattern is formed can be improved.

In the above, the ratio of the desired temperature distribution in S309a and the measurement difference s multi-temperature distribution in S308 may be calculated, and the ratio may be multiplied by the irradiation dose distribution as a coefficient. Further, a database in which the temperature distribution and the irradiation dose distribution are stored in association with each other by an experiment or a simulation may be prepared in advance, and the irradiation dose distribution may be selected so as to obtain a desired temperature distribution.

Further, in the present embodiment, the temperature distribution is measured by the infrared camera 310 inside the imprint device 300, but the temperature distribution may be measured outside the imprint device 300. For example, the temperature distribution when the substrate 10 is irradiated with light having a known irradiation light amount distribution using a light source having the same wavelength as the heating mechanism 60 may be measured by an infrared camera by detecting infrared light. Further, in S309 of the present embodiment, the control of feeding back to the irradiation amount distribution using the desired temperature distribution of the area to be processed 11 as a determination standard is performed, but open control may be used. Further, the shape difference and the relative positional deviation between the mold side pattern 30a and the area to be processed 11 based on the observation result by the observation unit 80 may be used as a determination criterion. For example, the mold side pattern and the shape of the area to be processed 11 in S303 are measured, and the correction amount of the mold and the area 11 to be processed in S304 is calculated constantly between S305 and S309, and the provisional irradiation amount distribution data 305 is updated as needed. You may. Then, the observation unit 80 measures the correction results of the mold side patterns of S306 and S307 and the area to be processed 11, and calculates the correction coefficient so as to minimize the correction residual by the least squares method or the like. Then, the irradiation dose distribution is calculated based on the obtained correction coefficient.

In the imprint apparatus 300, the correction coefficient is not determined based on the temperature distribution, but the temperature distribution is converted into the light absorption distribution in the region 11 to be processed, and then the provisional irradiation amount distribution data is obtained from the absorption rate distribution. The correction coefficient to be corrected may be determined.

[Sixth Embodiment]
The control unit 90 creates temporary irradiation amount distribution data by converting the typical reflectance obtained by measuring with the measuring unit 70 or the spread camera 70 into the absorption rate of the light 62. By measuring the information regarding the absorption of the light 62 in the area 11 to be processed, it is possible to create temporary irradiation amount distribution data capable of correcting the shape of the area 11 to be processed more accurately than when the absorption rate predicted by design is used. it can. If the shape of the area to be processed 11 can be corrected with high accuracy using the temporary irradiation amount distribution data, the temporary irradiation amount distribution data may be used as it is as the irradiation amount distribution data for imprint processing. Alternatively, as in the first to fifth embodiments, the control unit 90 has variations in the absorption rate of the light 62 for each lot of the substrate 10, variations in the absorption rate of the light 62 in the plane of the substrate 10, and for each chip region. The irradiation amount distribution may be created by correcting the provisional irradiation amount distribution data so as to reduce the variation in the absorption rate of the light 62.

[Other Embodiments]
In the first to fifth embodiments, the measurement of the shape of the mold side pattern and the processed region and the calculation of the correction amount of the mold side pattern and the shape of the processed region may be performed after the stamping operation.

A film having a high absorption rate for the purpose of flattening may be formed on the substrate 10 in a layer directly below the layer of the imprint material 20. The substrate 10 is easily deformed. The film is, for example, an SOC (Spin on carbon) film or an SOG (Spin on glass) film.

In the first to third embodiments and the fifth embodiment, the spread camera may be arranged for the purpose of detecting particles and detecting unfilled defects in the imprint material 20.

The correction value for correcting the temporary irradiation amount distribution determined based on the shape of the region 11 to be processed does not have to be a value multiplied by the temporary irradiation amount distribution. Any value may be used as long as it is used when performing arithmetic processing on the provisional irradiation amount distribution. Further, as the correction value, the average value of the correction values at a plurality of points may be used.

In the imprint method according to the first to third embodiments, the measurement unit 70 may be arranged outside the imprint device 100. For example, a reflectance measuring device (not shown) arranged outside the imprinting apparatus 100 may be used to measure the reflectance of the area to be processed 11 before the substrate 10 is carried in. When the reflectance is measured outside the imprint device 100, the measurement result is stored in the storage unit 92 via a wired or wireless line or by input by the user. The control unit 90 acquires the reflectance from the storage unit 92. The control unit 90 may acquire the reflectance directly from the measurement unit 70.

In the imprint method according to the embodiment, among the functions of the control unit 90, an apparatus having a function as a creating means for creating irradiation dose distribution data may be outside the imprint apparatus 100. The irradiation amount distribution created by the control unit 90 may be sent to the storage unit 92 by a storage information medium or wired or wireless communication. The functions included in the control unit 90 may be provided on one control board or may be provided on separate control boards as long as they have the respective functions.

The shape of the mold side pattern 30a and the shape of the area to be processed 11 may be the results measured in advance before the imprint processing shown in the flowchart of FIG. In this case, the step of S103 is a step of reading the result measured in advance from the storage unit 92.

The shape of the mold 30 may not be corrected, and only the shape of the area 11 to be processed may be corrected by thermal deformation.

The control board that executes the function as the calculation unit 76 of the measurement unit 70 may be arranged on the same control board as the control board that constitutes the control unit 90.

As the imprint material 20, a curable composition that cures when energy for curing is applied is used. Electromagnetic waves, radiation, heat and the like are used as energy for curing. The electromagnetic wave is, for example, light such as infrared rays, visible rays, and ultraviolet rays whose wavelength is selected from the range of 10 nm or more and 1 mm or less.

The curable composition is a composition that is cured by irradiation with light or radiation, or by heating. Of these, the photocurable composition that is cured by light may contain at least a polymerizable compound and a photopolymerization initiator, and may contain a non-polymerizable compound or a solvent, if necessary. The non-polymerizable compound is at least one selected from the group of sensitizers, hydrogen donors, internal release mold release agents, surfactants, antioxidants, polymer components and the like.

The imprint material is applied in the form of a film on the substrate by a spin coater or a slit coater. Alternatively, the liquid injection head may be applied on the substrate in the form of droplets or in the form of islands or films formed by connecting a plurality of droplets. The viscosity of the imprint material (viscosity at 25 ° C.) is, for example, 1 mPa · s or more and 100 mPa · s or less.
Good.

[Application to article manufacturing]
The pattern of the cured product formed by using the imprint device 100 is used permanently for at least a part of various articles or temporarily when producing various articles.

The article is an electric circuit element, an optical element, a MEMS, a recording element, a sensor, a mold, or the like. Examples of the electric circuit element include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensor, and FPGA.

Examples of the mold include a mold for imprinting. The pattern of the cured product is used as it is as a constituent member of at least a part of the above-mentioned article, or is temporarily used as a resist mask.

When the cured product pattern is used temporarily, the resist mask is removed after etching, ion implantation, or the like is performed as a step of processing the substrate 10.

Further, other well-known processing steps (development, oxidation, film formation, vapor deposition, flattening, imprint material peeling, dicing, bonding, packaging, etc.) may be performed.

Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments, and various modifications and modifications can be made within the scope of the gist thereof.

10 Substrate 11 Processed area 12 Substrate stage 20 Imprint material 30 type 40 Irradiation part 41 Ultraviolet rays (light)
50 Supply unit 60 Heating mechanism (heating means)
70 Measuring unit (measuring means)
90 Control unit (creating means)
92 Storage unit 100 Imprint device 210 Spread camera (measurement means)
310 infrared camera (measuring means)

Claims (12)

An imprinting device that forms a pattern of imprinting material on a substrate using a mold.
A heating means for irradiating the area to be processed on the substrate with light to heat the area to be processed,
A means for creating irradiation amount distribution data indicating an irradiation amount distribution of light to be irradiated to the area to be treated by the heating means, and a means for creating the irradiation amount distribution data.
It has a measuring means for measuring information on the absorption of light in the area to be processed.
The creating means corrects the provisional irradiation amount distribution data tentatively created based on the shape of the area to be processed before being heated by the heating means by using the measurement result of the measuring means, and the irradiation amount distribution. An imprinting device characterized by creating data. The imprint device according to claim 1, wherein the measuring means measures the information by receiving the reflected light of the light reflected in the area to be processed. The imprint device according to claim 2, wherein the measuring means receives the reflected light transmitted through the mold. The imprint device according to claim 2 or 3, wherein the wavelength band of light used by the measuring means for measurement includes the wavelength of light used for heating by the heating means. The imprint according to claim 1, wherein the measuring means measures the information by receiving synchrotron radiation generated by irradiating the area to be processed with the light. Printing device. The creating means is characterized in that the irradiation dose distribution data is created by performing arithmetic processing including an operation of multiplying the provisional irradiation dose distribution data by a correction value determined based on the measurement result of the measuring means. The imprint device according to any one of claims 1 to 5. The creating means creates the irradiation dose distribution data by performing arithmetic processing including an operation of multiplying the provisional irradiation dose distribution data by a correction value determined based on the measurement result of the measuring means.
The light used for heating by the heating means is heating light.
The correction value is determined based on the absorption rate of the heating light in the area to be processed and the reflectance measured by the measuring means, which are used to create the provisional irradiation amount distribution data. The imprinting apparatus according to any one of claims 2 to 4 , wherein the ratio is the absorption rate of the heating light in the above. There are a plurality of the processed regions on the substrate, and the measuring means receives the light reflected by each of the plurality of processed regions to obtain the reflectance in each of the plurality of processed regions. Measure and
The imprint according to any one of claims 1 to 7, wherein the creating means creates the irradiation dose distribution data based on the measurement result in each of the processed regions of the measuring means. Printing device. The processed region includes a plurality of chip regions, and the measuring means measures the reflectance at each of the plurality of locations by receiving light reflected at the plurality of locations within the chip region, and prepares the above. The imprint device according to any one of claims 1 to 5, wherein the means creates the irradiation dose distribution data based on the measurement result in the chip region of the measuring means. The imprint according to any one of claims 1 to 9, wherein the irradiation dose distribution data is irradiation dose distribution data that reduces the shape difference between the pattern region of the type and the region to be processed. Printing device. An imprinting method in which a pattern of an imprinting material is formed on a substrate using a mold.
The process of supplying the imprint material to the area to be processed on the substrate, and
A step of measuring information on absorption of light that heats the area to be processed in the area to be processed, and
A step of creating temporary irradiation amount distribution data showing an irradiation amount distribution of light irradiating the area to be processed based on the shape of the area to be processed before heating, and
The step of creating the irradiation dose distribution data by correcting the provisional irradiation dose distribution data created in the above step using the measurement result obtained in the measurement step, and
Based on the created irradiation amount distribution data, the imprint material is irradiated with the light to deform the area to be processed, and the imprint material is cured in a state where the imprint material and the mold are in contact with each other to perform the treatment. An imprinting method comprising a step of forming a pattern of the imprinting material on an area. A step of forming a pattern of the imprint material on a substrate by using the imprint method according to claim 11.
A method for producing an article, which comprises a step of processing a substrate on which the pattern is formed in the step.