TWI611254B - Method of manufacturing a photomask, pattern drawing device, method of inspecting a photomask, device for inspecting a photomask and method of manufacturing a display device - Google Patents

Abstract

The invention provides a manufacturing method of a photomask capable of improving the accuracy of the coordinates of a pattern formed on a transferred body.

The manufacturing method of the photomask of the present invention includes the steps of preparing pattern design data A; preparing the thickness distribution data T indicating the thickness of the substrate; and preparing a transfer surface shape indicating the shape of the main surface when the photomask is held in the exposure device. Step of data C; step of obtaining the difference data F by using the thickness distribution data T and the transfer surface shape data C; estimating the coordinate offset of a plurality of points on the main surface corresponding to the difference data F for drawing Steps of coordinate offset data G; and drawing steps of drawing on a mask substrate using the coordinate offset data G and pattern design data A for drawing.

Description

Photomask manufacturing method, drawing device, photomask inspection method, photomask inspection device, and display device manufacturing method

The present invention relates to a photomask that can be preferably used in the manufacture of a semiconductor device or a display device (LCD (Liquid Crystal Display, Liquid Crystal Display), organic EL (Electroluminescence, etc.)), and relates to a photomask Manufacturing method and device, inspection method and device.

It is desirable to increase the accuracy of the pattern for transfer formed on the photomask, and further, it is desirable to increase the accuracy of inspection of the pattern for transfer formed.

Patent Document 1 (Japanese Patent Laid-Open No. 2010-134433) describes a drawing method and a drawing device that can improve the accuracy of coordinates when a mask pattern is transferred to a transfer target. In particular, Patent Document 1 describes a method for obtaining corrected drawing data in order to eliminate the following problem, which is a film surface (pattern forming surface) when a transfer pattern is drawn in a mask manufacturing step. The shape was different from that at the time of exposure, and no pattern as designed was formed on the transferee.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-134433

In manufacturing a display device, a photomask having a pattern for transfer based on a design of a device to be obtained is often used. As a device, a liquid crystal display device or an organic EL display device represented by a smart phone or a tablet terminal is required to have a bright image that is bright, saves power, has a fast operation speed, and has a high resolution. Therefore, with regard to the photomask used for the above-mentioned applications, new technical problems are revealed by the inventors.

If detailed, it is necessary to increase the pixel density in order to clearly display fine images. At present, it is intended to realize a device with a pixel density exceeding 400 ppi (pixel per inch, pixels per inch). Therefore, the design of the pattern for transfer of the photomask tends to be miniaturized and high-density. In addition, many electronic devices including display devices are formed three-dimensionally by laminating a plurality of layers in which a fine pattern is formed. Therefore, it is important to improve the coordinate accuracy of the multiple layers and the matching of the mutual coordinates. That is, if the accuracy of the pattern coordinates of each layer does not satisfy a certain level, there will be disadvantages such as failure to perform appropriate operations in the completed device. Therefore, the allowable range of the coordinate offset required for each layer tends to be smaller and smaller.

In addition, Patent Document 1 describes a situation in which the shape change amount of the film surface in the drawing step of the mask base and the shape change of the film surface shape during exposure are estimated, and are applied to the shape change amount based on the estimated shape change amount. The drawing design drawing data is amended. In Patent Document 1, a method is described in which the film surface of the substrate (the surface on the transparent substrate refers to the side where the film is formed, and the surface on the photomask base refers to the surface on which the film is formed) at the stage of drawing the transfer pattern. In the photomask refers to the surface on which the pattern is formed), from the deformation factors of the ideal plane, the part that remains at the time of exposure is distinguished from the part that disappears at the time of exposure to obtain corrected drawing data.

When drawing a pattern on a photoresist substrate with a photoresist by a drawing device, the photomask The substrate is placed on the workbench of the drawing device with the film surface facing up. At this time, as deformation factors from the ideal plane of the surface shape of the film surface of the mask base, it is considered that there are four deformation factors described below.

(1) Insufficient flatness of the workbench; (2) Deflection of the substrate due to foreign objects sandwiched on the workbench; (3) Concavity and convexity of the base film surface of the photomask; and (4) Back surface of the photomask substrate The deformation of the film surface caused by the unevenness (that is, the deformation of the film surface caused by the unevenness of (3) and the thickness of the substrate); therefore, the surface shape of the mask base in this state is formed by the accumulation of the above-mentioned 4 deformation factors . Then, the mask base in this state is drawn.

On the other hand, when the photomask is mounted on an exposure device, the film is face down and is fixed by supporting only the outer edge portion of the photomask. A transfer target having a photoresist film formed (also referred to as a target to be processed by etching or the like after the pattern is transferred) is placed under the photomask and irradiated from above the photomask (from the back side). Light of exposure. In this state, among the above-mentioned four deformation factors, (1) insufficient flatness of the table and (2) deflection of the substrate due to foreign objects sandwiched on the table disappear. Also, in this state, (4) the unevenness on the back surface of the substrate remains, but the surface shape of the back surface on which no pattern is formed does not affect the transfer of the front surface (pattern forming surface). On the other hand, the deformation factor that remains when the photomask is used in the exposure apparatus is the above (3).

That is, the deformation factors of (1), (2), and (4) exist during drawing and disappear when exposed. This change causes the coordinates to shift between the time of drawing and the time of exposure. Therefore, as long as the surface shape derived from the deformation factors (1), (2), and (4) above is changed from the ideal plane, the design drawing data is corrected to be the drawing data. On the other hand, 3) The amount of surface shape change of the deformation factor is reflected in the above correction, and a photomask having more accurate transfer performance of coordinate design data can be obtained.

Therefore, according to the method of Patent Document 1, it is possible to improve the coordinate accuracy of the pattern formed on the object to be transferred.

On the other hand, the photomask in the exposure device is held and supported approximately horizontally by a holding area near the outer edge of the substrate by a holding member of the exposure device. At this time, the substrate is deformed due to the compulsory restriction of the holding portion. Furthermore, in the case of a photomask for manufacturing a display device or the like, since a large-area substrate is supported near the outer edge of the substrate, deflection due to its own weight also occurs. In this case, the deformation of the film surface also affects the area where the pattern of the photomask is formed, which may cause the accuracy of its coordinates to deteriorate. The present inventors have found that if the miniaturization or high integration of patterns of high-performance display devices and the like currently developed is considered, such fine effects need to be considered.

For example, a device such as a display device is formed by laminating a patterned thin film, but each layer of the lamination is formed by a patterner for transfer that each of the photomasks has. Of course, each photomask used is manufactured based on strict quality control. However, since the photomasks are different, it is difficult to make the surface flatness equal to the perfect ideal plane, and it is also difficult to make the shape of the film surface exactly the same as that of a plurality of photomasks.

Therefore, the shape of the film surface of each photomask has individual differences. If the shape of the film surface is corrected by taking into account the shape of the film surface exhibited when these photomasks are held in the exposure device, a higher coordinate accuracy can be formed Pattern for transfer.

That is, the present inventor has found that the method of Patent Document 1 is advantageous in that it prevents the deterioration of the coordinate accuracy caused by the difference between the film surface posture during the drawing and the exposure, and it has a plural number in order to further improve the accuracy. The yield of the device of each layer also takes into account the individual differences in the shape of the film surface of the mask substrate used in each layer, and the effect caused by the force equal to the force experienced in the exposure device, thereby substantially eliminating the effect caused by the effect. Degradation of transferability.

In addition, in the above-mentioned Patent Document 1, a procedure is described in which a mask base is placed on a table of a drawing device with the film surface as an upper side, and the height distribution of the surface on the upper side of the mask base is performed in this state. Determination. This step is useful in that the results of the four deformation factors described above can be quantified. However, this step has an increase in There are disadvantages of time. The present inventor has also focused on the following situation: since the occupation time of the drawing device has a large influence on the production efficiency or cost of the photomask, there is a technical problem of improving its potential.

Therefore, an object of the present invention is to provide a method for manufacturing a photomask, a drawing device, a method for inspecting a photomask, an apparatus for inspecting a photomask, and the like, which can improve the accuracy of the coordinates of a pattern formed on a transferred object, in order to solve the above problems. Manufacturing method of display device.

In order to solve the above problems, the present invention has the following configuration.

(Composition 1)

A manufacturing method of a photomask, which includes a photomask base on which a thin film and a photoresist film are formed on a main surface of a substrate, and draws a specific transfer pattern by a drawing device, and has the following characteristics: The step of preparing pattern design data A for the design of the pattern for transfer; the step of preparing the thickness distribution data T indicating the thickness distribution of the substrate; the step of preparing the transition of the shape of the main surface when the mask is held on the exposure device. The step of printing surface shape data C; the step of obtaining the drawing difference data F using the thickness distribution data T and the transfer surface shape data C; estimating the coordinate offset of a plurality of points on the main surface corresponding to the drawing difference data F A step of obtaining coordinate drawing offset data G for drawing; and a drawing step of drawing on the mask base using the drawing offset data G for drawing and the pattern design data A.

(Composition 2)

A manufacturing method of a photomask, which includes a photomask base having a thin film and a photoresist film formed on a main surface of a substrate, and drawing a specific transfer pattern by a drawing device. And has the steps of preparing pattern design data A based on the design of the specific transfer pattern, preparing thickness distribution data T indicating the thickness distribution of the substrate, and substrate surface shape data indicating the surface shape of the main surface. Step B; the displacement of the surface shape when the photomask is held in the exposure device is reflected in the substrate surface shape data B, and a transfer surface shape indicating the shape of the main surface when held in the exposure device is obtained Step of data C; step of obtaining the drawing difference data F using the thickness distribution data T and the transfer surface shape data C; estimating the coordinate offset of a plurality of points on the main surface corresponding to the drawing difference data F and A step of obtaining the drawing coordinate offset data G; and a drawing step of drawing on the mask base using the drawing coordinate offset data G and the pattern design data A.

(Composition 3)

For example, in the manufacturing method of the photomask constituting 1 or 2, the amount of deformation of the main surface caused by the deflection of the weight of the substrate among the deformations of the main surface generated when the substrate is held in the exposure device is obtained. The dead weight deformation amount data R is used in the step of obtaining the drawing difference data F, using the thickness distribution data T, the transfer surface shape data C, and the dead weight deformation amount data R.

(Composition 4)

For example, in the manufacturing method of the photomask of 2, wherein the above-mentioned substrate surface shape data B is in a state of holding the above-mentioned photomask base or the substrate for making the above-mentioned photomask base in such a manner that the main surface becomes substantially vertical. , The positions of the plurality of measurement points on the main surface are measured and obtained.

(Composition 5)

For example, the manufacturing method of the photomask of any one of 1 to 4, wherein the thickness distribution data T is obtained by holding the photomask substrate in such a manner that the main surface becomes substantially vertical or used to make the photomask substrate. In the state of the substrate, the positions of the plurality of measurement points on the main surface are measured and determined.

(Composition 6)

For example, if the manufacturing method of the photomask of any one of 1 to 5 is used, the coordinate offset unique data Q related to the coordinate offset component inherent to the drawing device is obtained in advance, and in the drawing step, the drawing coordinates are used. The offset data G, the pattern design data A, and the coordinate offset specific data Q are drawn on the mask base.

(Composition 7)

If the manufacturing method of the photomask of any one of 1 to 6 is used, in the step of obtaining the transfer surface shape data C described above, a finite element method is used.

(Composition 8)

For example, in the manufacturing method of the photomask constituting any one of 1 to 6, in the drawing step, the correction pattern data obtained by correcting the pattern design data A based on the coordinate offset data G for the drawing is used. H is drawn.

(Composition 9)

For example, in the manufacturing method of the photomask constituting any one of 1 to 6, in the above-mentioned drawing step, based on the above-mentioned drawing coordinate offset data G, the coordinate system possessed by the above-mentioned drawing device is corrected, and the obtained correction is used. The coordinate system and the above-mentioned pattern design data A are drawn.

(Composition 10)

In the manufacturing method of the photomask according to any one of 1 to 9, when the photomask is held in the exposure device, a plurality of holding points held by the holding member are arranged on a plane.

(Composition 11)

A drawing device is used for drawing a pattern for a transfer on a mask base having a thin film and a photoresist film formed on a main surface of a substrate, and has an input mechanism for inputting pattern design information of the above-mentioned pattern for transfer. A, thickness distribution data T indicating the thickness distribution of the substrate, and transfer surface shape data C indicating the main surface shape of the substrate in a state where the substrate is held in an exposure device; a calculation mechanism that uses the thickness distribution data T and The transfer surface shape data C calculates the coordinate offset data G for drawing at a plurality of points on the main surface; and a drawing mechanism that uses the coordinate offset data G for drawing and the pattern design data A for the above Painted on the mask base.

(Composition 12)

A drawing device is used for drawing a pattern for a transfer on a mask base having a thin film and a photoresist film formed on a main surface of a substrate, and has an input mechanism for inputting pattern design information of the above-mentioned pattern for transfer. A, thickness distribution data T indicating the thickness distribution of the substrate, substrate surface shape data B indicating the shape of the main surface of the substrate, information related to the holding state when the substrate is held in an exposure device, and materials including the substrate Substrate information of physical properties; an arithmetic unit that can calculate the main surface shape of the substrate indicated by the state held in the exposure device using the substrate surface shape data B, the information related to the holding state, and the substrate information. Transfer surface shape data C, and use the thickness distribution data T and the transfer surface shape data C to calculate coordinate drawing offset data G for a plurality of points on the main surface; and a drawing mechanism using the drawing coordinates The offset data G and the pattern design data A are drawn on the photomask base.

(Composition 13)

For example, the drawing device of configuration 12 further includes a memory mechanism that stores the main surface of the main surface caused by the self-deflection of the substrate among the deformations of the main surface generated when the substrate is held in the exposure device. The deformation amount data of the dead weight deformation amount R, the above-mentioned arithmetic unit performs the calculation using the dead weight deformation amount data R.

(Composition 14)

If the drawing device of 12 or 13 is configured, it has a memory mechanism that stores coordinate offset unique data Q related to the coordinate offset component inherent to the drawing device, and the arithmetic unit uses the coordinate offset unique data Q. Perform calculations.

(Composition 15)

A photomask inspection method for inspecting a photomask having a pattern for transferring a film patterned on a main surface of a substrate using an inspection device, and the method includes: placing the photomask on the inspection In the state of the device on the table, the step of measuring the coordinates of the transfer pattern formed on the main surface to obtain the pattern coordinate data L; preparing the thickness distribution data T indicating the thickness distribution of the substrate; obtaining the expression The step of transferring the surface shape data C of the shape of the main surface when the mask is held in the exposure device; the step of obtaining the difference data J using the thickness distribution data T and the transfer surface shape data C; the estimation and the inspection The step of obtaining the coordinate offset data K for inspection by the coordinate offsets of a plurality of points on the main surface corresponding to the difference data J; and using the above-mentioned coordinate offset data K for inspection and the above-mentioned pattern coordinate data L The inspection procedure of the above-mentioned inspection of the transfer pattern is performed.

(Composition 16)

A method for inspecting a photomask, which uses an inspection device to A person who inspects a pattern with a transfer pattern formed by patterning a film, and has the above-mentioned transfer formed on the main surface in a state where the photomask is placed on a table of the inspection device. The step of obtaining the pattern coordinate data L by measuring the coordinates of the printed pattern; the step of preparing the thickness distribution data T indicating the thickness distribution of the substrate and the substrate surface shape data B indicating the surface shape of the main surface; maintaining the mask The shift in the surface shape when in the exposure device is reflected in the substrate surface shape data B, and a step of obtaining the transfer surface shape data C indicating the shape of the main surface when held in the exposure device; using the thickness distribution The step of obtaining the inspection difference data J from the data T and the transfer surface shape data C; estimating the coordinate offsets of a plurality of points on the main surface corresponding to the inspection difference data J to obtain the inspection coordinate offset data Step K; and using the above-mentioned inspection coordinate offset data K and the above-mentioned pattern coordinate data L to check the above-mentioned transfer pattern Check the steps.

(Composition 17)

For example, if the inspection method of the photomask of 15 or 16 is formed, the amount of deformation of the main surface caused by the deflection of the weight of the substrate among the deformations of the main surface generated when the substrate is held in the exposure device is obtained. The weight-deformation amount data R, in the step of obtaining the inspection difference data J, the thickness distribution data T, the transfer surface shape data C, and the weight-deformation amount data R are used.

(Composition 18)

For example, if the inspection method of the photomask constituting any of 15 to 17 is obtained, the inspection coordinate offset constant data S related to the coordinate offset component inherent to the inspection device is obtained in advance. The inspection step described above uses the inspection coordinate offset. The transfer pattern K, the pattern coordinate data L, and the check coordinate offset constant data S are used to check the transfer pattern. check.

(Composition 19)

In the inspection method of the photomask constituting any one of 16 to 18, in the step of obtaining the transfer surface shape data C, a finite element method is used.

(Composition 20)

For example, the inspection method of the photomask constituting any one of 15 to 19, wherein the inspection of the transfer pattern is performed by using the revised design data M, obtained by reflecting the inspection coordinate offset data K on the pattern design data A, And the pattern coordinate data L described above.

(Composition 21)

For example, the inspection method of the photomask constituting any of 15 to 19, wherein the inspection of the transfer pattern is performed by using the corrected coordinate data N obtained by reflecting the inspection coordinate offset data K on the pattern coordinate data L. And pattern design information A.

(Composition 22)

A method for manufacturing a photomask, comprising: a step of preparing a photomask substrate having a thin film and a photoresist film formed on a main surface; a step of patterning the thin film; and using any one of the constitutions 15 to 21 Inspection steps of the inspection method of the photomask.

(Composition 23)

A method for manufacturing a display device, comprising: preparing a photomask having a pattern for transfer formed on a main surface and manufacturing the photomask by a manufacturing method such as 1 or 2; and exposing the photomask to the photomask. The device substrate having the processed layer is subjected to a pattern transfer step.

(Composition 24)

A method for manufacturing a display device includes a plurality of photomasks and an exposure device each having a pattern for transfer formed on a main surface thereof, and sequentially Those who perform pattern transfer on a plurality of layers to be processed are characterized in that, as the plurality of photomasks, those manufactured by a method for forming a photomask according to any one of 1 to 10 are used.

(Composition 25)

An inspection device for a photomask, which inspects a photomask having a pattern for transferring a film formed by patterning a film on a main surface of a substrate, and includes a coordinate measuring mechanism that performs the above-mentioned formation on the main surface. The pattern coordinate data L is obtained by measuring the coordinates of the pattern for transfer. The input mechanism inputs the pattern design data A of the transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and indicating that the substrate is held in an exposure device. The state of the main surface shape of the substrate is the transfer surface shape data C; the calculation unit uses the thickness distribution data T and the transfer surface shape data C to calculate the coordinate offsets for inspection of a plurality of points on the main surface Data K; and an inspection mechanism that uses the above-mentioned inspection coordinate offset data K and pattern design data A to inspect the pattern for transfer of the photomask.

(Composition 26)

An inspection device for a photomask, which inspects a photomask having a pattern for transferring a film formed by patterning a film on a main surface of a substrate, and includes a coordinate measuring mechanism that performs the above-mentioned formation on the main surface. The pattern coordinate data L is obtained by measuring the coordinates of the pattern for transfer. The input means inputs the pattern design data A of the transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and the shape of the main surface of the substrate. The substrate surface shape data B, the information related to the holding state when the substrate is held in the exposure device, and the substrate information including the physical property values of the substrate material; A computing unit that can use the substrate surface shape data B, the information related to the holding state, and the substrate information to calculate transfer surface shape data C indicating the main surface shape of the substrate held in the exposure device; and Use the thickness distribution data T and the transfer surface shape data C to calculate the inspection coordinate offset data K of a plurality of points on the main surface; and an inspection mechanism using the inspection coordinate offset data K and a pattern The design data A is used to check the pattern for transfer of the photomask.

According to the present invention, it is possible to provide an efficient photomask manufacturing method, a drawing device, a photomask inspection method, a photomask inspection device, and a display device capable of improving the accuracy of the coordinates of a pattern formed on a transferred object. Production method.

10‧‧‧Workbench

11‧‧‧painting agency

12‧‧‧Measurement agency

13‧‧‧Photomask base (substrate)

14‧‧‧ film

15‧‧‧Portrayal data production agency

20‧‧‧ surface

21‧‧‧ datum surface

d‧‧‧offset

H‧‧‧ height

t‧‧‧thickness

X‧‧‧ direction

Y‧‧‧ direction

Z‧‧‧ direction

Φ‧‧‧angle

△ X‧‧‧X-axis offset

△ Y‧‧‧Y-axis offset

FIG. 1 (a) is a side view of a substrate held in such a manner that the main surface becomes parallel to the vertical direction, and FIG. 1 (b) is a front view of the substrate.

FIG. 2 (a) is a cross-sectional view of a substrate with a plurality of measurement points set, and FIG. 2 (b) is a front view of the substrate.

Figure 3 (a) is a cross-sectional view of a mask model used in the finite element method, and Figure 3 (b) is a front view of the mask model.

Fig. 4 (a) is a sectional view of a mask model arranged with the film surface as the upper side, Fig. 4 (b) is a sectional view of a mask model arranged with the film surface as the lower side, and Fig. 4 (c) is taken with A front view of a mask model arranged with the film surface as the upper side, and FIG. 4 (d) is a front view of the mask model arranged with the film surface as the lower side.

Fig. 5 (a) is a cross-sectional view of a mask model showing a holding position using a holding member and a displacement of the mask in a holding state according to the first embodiment. Fig. 5 (b) is a front view of the mask model of Fig. 5 (a) according to the first embodiment, and a holding position using a holding member is shown by a broken line.

FIG. 6 (a) is a cross-sectional view showing an example of a force applied to a photomask held by an exposure apparatus in Embodiment 1. FIG. FIG. 6 (b) is a diagram showing an example of the area where the vacuum pressure is applied to the photomask and the holding position of the holding member in the first embodiment.

FIG. 7 is a schematic diagram of a hexahedron constituting a mask model of Embodiment 1. FIG.

FIGS. 8 (a) to (e) show that in Embodiment 1, after the transfer surface shape data C is obtained from the substrate surface shape data B, it is obtained by the difference between the substrate thickness distribution data T and the transfer surface shape data C. A pattern diagram of the steps from the drawing of the difference data F to the drawing coordinate offset data G from the drawing of the difference data F.

FIG. 9 is a schematic diagram for calculating the relationship between the shape change of the film surface and the coordinate offset caused by the change.

Figs. 10 (a) to (e) show that after obtaining the inspection difference data J from the difference between the substrate thickness distribution data T and the transfer surface shape data C, the inspection coordinate offset data K is obtained from the inspection difference data J. A schematic diagram of the steps so far.

FIG. 11 is a conceptual diagram of a drawing device used in a method of manufacturing a mask according to an embodiment.

FIG. 12 is a graph showing the coordinate deviation of the measurement point due to the height of the substrate surface as a vector.

FIG. 13 (a) is a cross-sectional view showing an example of a force applied to a mask held by an exposure apparatus in Embodiment 2. FIG. Fig. 13 (b) is a view showing an example of a holding position of a holding member in the second embodiment.

14 (a) to (e) show the difference between the self-transferred surface shape data C and the reference shape data C1 reflecting the self-deflection of an ideal substrate in Embodiment 1 to obtain the transfer surface correction data D from which the self-deflection component is removed. Step pattern diagram.

15 (a) to (d) show drawing difference data F obtained from the difference between the thickness distribution data T of the substrate and the transfer surface correction data D in the second embodiment, and the drawing coordinate offset is obtained from the drawing difference data F. Schematic diagram of steps for measuring data G.

16 (a) to (d) show the difference between the transfer surface correction data D and the thickness distribution data T of the substrate in which the self-deflection component has been removed in Embodiment 2, and the inspection difference data J is obtained, and the inspection difference data J is obtained from the inspection A pattern diagram of the steps of obtaining the coordinate offset data K for inspection.

17 (a) and 17 (c) show the coordinate measurement results of the pattern drawn on the test mask. 17 (b) and 17 (d) show the results of simulating the displacement of the coordinates when the test mask is set in the exposure device.

<Embodiment 1> (drawing)

The manufacturing method of the mask of embodiment of this invention has the following steps.

Prepare mask base

In the embodiment of the present invention, a pattern for transferring based on a device to be obtained is formed on a mask base on which one or a plurality of films are formed on the main surface of the substrate, and a photoresist film is formed to form the pattern. The depiction of the mask. Therefore, a photomask base having the above thin film and photoresist film formed on one main surface of the substrate is prepared.

The prepared mask substrate can be a known one.

As the substrate, a transparent substrate such as quartz glass can be used. There is no limitation on the size or thickness, but as one that can be used in the manufacture of display devices, one with a thickness of 300mm to 1800mm and a thickness of about 5 to 15mm can be used.

In this specification, there are cases where a substrate having one or more films formed on the main surface thereof or a photoresist film formed on the film is referred to as a "substrate" (or, Photomask base substrate, photomask substrate).

Furthermore, in the step of measuring the flatness or thickness distribution (hereinafter, also referred to as TTV (total thickness variation)) of the main surface of the substrate, a thin film formed on the main surface is not substantially generated. Or the thickness of the photoresist film. The reason is that the film thickness of the thin film or photoresist film is sufficiently small to not substantially affect the above measurement.

As a film, in addition to a light-shielding film (optical density OD = 3 or more) that shields the light exposed when a photomask is used, it can be a translucent film that transmits a part of the exposed light (the light transmittance of the exposure is 2 to 80%) ), Or it can be a phase shift film (for example, the phase shift of the exposed light is 150 ~ 210 degrees, the light transmittance of the exposure is about 2 ~ 30%) or the resistance to control the reflectivity of light Optical films such as reflective films. Furthermore, the thin film may include a functional film such as an etching stopper film. It can be a single film or a laminate of multiple films. For example, a light-shielding film or an anti-reflection film containing Cr, a semi-transparent film or a phase shift film containing a Cr compound or a metal silicide can be applied. A photomask substrate having a plurality of films laminated can also be applied. By applying the method of the present invention to the patterning of each of the plurality of films, a photomask having excellent transfer accuracy can be manufactured.

The photoresist formed on the outermost surface may be positive or negative. As a photomask for a display device, a positive type is useful.

I Steps to prepare pattern design information A

The so-called pattern design data is data of a pattern for transfer designed based on a device (display device, etc.) to be obtained.

The use of the device manufactured by the photomask of the present invention is not limited. For example, an excellent effect can be obtained by applying the present invention to each layer of each component constituting a liquid crystal display device or an organic EL display device. For example, the present invention can be preferably applied to a line and gap pattern having a pitch of less than 7 μm (for a line or gap with a critical width (CD: Critical Dimension) of 4 μm or a part of less than 3 μm, etc.) or a diameter A mask for display devices having a fine design of a hole pattern of 1.5 to 5 μm, especially 1.5 to 3.5 μm.

If the pattern design data is directly used for drawing without correction, it will be used for transfer due to the difference in the shape of the film surface when drawing (when placed in the drawing device) and when exposed (when kept in the exposure device). When the pattern is formed on the object to be transferred, the coordinate accuracy becomes insufficient. Therefore, correction is performed by the following steps.

II Obtain the thickness distribution data T, which represents the thickness distribution of the substrate, and the surface shape data of the substrate Step B

In this step, as for the order of obtaining the thickness distribution data T and the substrate surface shape data B, either one may be performed first, and it may be obtained in different steps, or may be obtained in one step. Here, a case where the measurement is performed in one step using the same flatness measuring device is exemplified.

For example, the substrate to be measured is held so that the main surface becomes substantially vertical. That is, it can be measured by a flatness measuring machine in a state where the deflection due to its own weight does not substantially affect the shape of the front and back surfaces (see FIG. 1).

The measurement can be performed by a flatness measuring machine using an optical measurement method such as detecting the reflected light of the irradiated light (laser or the like). Examples of the measurement device include a flatness measuring machine FTT series manufactured by Kuroda Seiko Co., Ltd., or those described in Japanese Patent Laid-Open No. 2007-46946.

At this time, the intersection points (square points) of a plurality of squares drawn in the XY direction are set on the main surface at equal intervals (the separation distance is set as the pitch P), and the intersections can be set as measurement points (see FIG. 2). .

For example, a flatness measuring machine having a function of using a substantially vertical plane as a reference plane and measuring the distance between the reference plane and the Z-direction (see FIG. 2) of each of the measurement points at each measurement point can be used. By this measurement, the flatness of the main surface of the substrate can be grasped, thereby obtaining the substrate surface shape data B. An example in which the pitch P is set to 10 mm is shown in FIG. 2.

As shown in FIG. 2 (a), the heights in the Z direction of all measurement points on the main surface were measured. Thereby, the substrate surface shape data B is obtained in the form of a flatness map (see FIG. 8 (a)).

Furthermore, when the substrate surface shape data B is obtained, the same measurement is performed on the back surface side of the substrate (the surface opposite to the main surface that becomes the film surface) by setting a measurement point at a position corresponding to the film surface side, whereby The shape data of the back surface of the substrate and each measurement point can be obtained in advance The thickness T of the substrate (the distance between the film surface and the back surface) is a distribution data T (see FIG. 2 (a)). The thickness distribution of the substrate is also described as TTV (Total thickness variation). The thickness distribution data T can be used in the later stage.

With regard to the setting of the measurement points, the separation distance P can be determined from the viewpoint of the measurement time of the size of the substrate and the viewpoint of correction accuracy. The separation distance P can be set to, for example, 2 ≦ P ≦ 20 (mm), and more preferably 5 ≦ P ≦ 15 (mm).

After measuring the surface flatness on the film surface side, the least square plane can be obtained from the measured values. Let the center of the face be the origin O.

III Steps to Obtain the Shape Information C of the Transfer Surface

Next, when the substrate becomes a photomask, it is considered that the photomask is held in an exposure device. The photomask provided in the exposure apparatus is maintained so that the film surface faces downward. In this state, the film surface (transfer surface) of the substrate is subjected to a force depending on the state according to the holding state, so that its shape changes. This also becomes a different deformation depending on the shape of the holding member.

III-1 way <1>

Here, the case where the exposure apparatus which hold | maintains the mask substrate by the method shown in FIG.6 (a) (b) is demonstrated.

In the exposure machine, the photomask substrate is supported substantially horizontally with the film surface side (pattern forming surface) facing downward, and is held in contact with a holding member near the outer edge.

The substrate held approximately horizontally is deflected by its own weight, and the position near the center of the main plane is lower than the vicinity of the outer edge. Therefore, for the purpose of counteracting the weight of the mask and reducing the deflection of the transfer surface of the mask, setting a specific area on the back of the mask (the side opposite to the film surface side) allows the force caused by vacuum pressure to be applied to This area (Figure 6 (b)). In this case, the force applied to the mask changes according to the area or the size of the vacuum pressure. Here, the case where the vacuum pressure is applied refers to a state where the photomask is sucked upward by decompressing the space on the back surface of the photomask transfer surface.

The surface shape (transfer surface shape) of the substrate under such a force can be measured. That is, a required number of measurement points are set on the film surface of the photomask provided in the state of the exposure machine, and the shape measurement is performed by an optical mechanism or the like, thereby obtaining a mapping table as shown in FIG. 10 (b), for example. The measurement point is preferably the same position as the measurement point used in the substrate surface shape data B described above.

However, the present invention can be carried out without measurement.

For example, it is possible to estimate the displacement generated in the mask film surface maintained in the state of the exposure device, and reflect the displacement in the substrate surface shape data B to obtain the transfer surface shape data C (see FIG. 8 (b)). That is, information related to the holding state that affects the shape of the main plane when the photomask is held in the exposure device (including holding conditions using a holding member and vacuum pressure conditions to counteract its own weight) can be used for simulation. The transfer surface shape data C.

In this step, it is preferable to apply the finite element method. Therefore, a mask model was prepared as a preparation stage (FIG. 3).

The shape data of the two surfaces were obtained by measuring the flatness of the film surface side and the back surface side. Here, an imaginary measurement point is added to the outermost measurement point at a distance of 1 pitch from the substrate end, and the height in the Z direction of the imaginary measurement point is set to the measurement of the outermost periphery. Point the same height. This process is used to accurately reflect the size and weight of the substrate in the finite element method used below. In addition, a virtual measurement point is also set between the corresponding measurement points on the film surface side and the back surface side, and the center value of the corresponding two measurement values is set. Then, adjacent measurement points (including virtual measurement points) are connected in a straight line (see FIGS. 3 (a) and (b)).

In addition, the above-mentioned imaginary measurement points are not limited to the case where the measurement values are provided at the center of the measurement values on the film surface and the back surface, and two or three points may be provided at regular intervals in the thickness direction.

Figures 4 (a) ~ (d) are schematic diagrams showing the photomask model viewed from the front and back surfaces and sections.

Next, in this photomask model, the photomask is set to be held and held in the exposure device. A plurality of holding points for the component. The plurality of holding points are points that are held and limited by the holding member by contact or adsorption when the photomask is mounted in the exposure device, which differs depending on the manufacturer, generation, or size of the exposure device, and therefore is based on the exposure used. Device.

In this form, as an example, a description will be given of a case where a quadrangular band-shaped holding member is disposed in parallel with the four sides at a specific distance from the outer periphery near the four sides of the outer periphery of the main surface of the substrate. It is in contact with the film surface side of the substrate so as to surround the pattern formation region for transfer (the dotted line in FIG. 5 (b)).

That is, in the model shown in Figs. 6 (a) and (b), the measurement point on the broken line is set as the holding point. In the exposure apparatus, the holding point is restricted by being brought into contact with the holding member to be displaced, whereby the displacement may spread to the entire shape of the film surface due to the physical properties of the substrate.

Furthermore, as described above, since a deflection is generated by applying a self-weight to the substrate, an upward force for reducing the deflection is applied. This is performed by applying a vacuum pressure from above the substrate (back side) (FIG. 6 (a)). As shown in FIG. 6 (b), the area to which the vacuum pressure is applied may be a quadrangular area including the center of the main surface of the substrate.

In the model shown in FIG. 5 (a), the amount of forced shift is set so that the position of the measurement point that becomes the holding point becomes zero on the Z axis. Moreover, the zero position in the Z-axis direction refers to the least square plane that has been set (and the origin above the least square plane). For example, if the value of the flatness of the film surface side at a certain measurement point which is a holding point is 5 μm, the forced shift amount of the measurement point becomes “−5 μm”.

Here, it is preferable to set the amount of the vacuum pressure applied from the back surface side to the minimum flatness of the film surface.

Furthermore, when evaluating the flatness of a specific surface, there is a case where the distance between the surface and the reference surface (in many cases, a surface approximately parallel to the specific surface is used as the reference surface). Expressed as the difference between the maximum and minimum values of the distance. That is, when the value of the flatness is small, it means that the surface is flatter with less unevenness.

Therefore, in order to determine the amount of vacuum pressure applied to the simulation, as long as the vacuum pressure applied to the back surface of the photomask substrate is changed, the vacuum pressure when the flatness of the film surface becomes the minimum can be obtained. In general, the displacement caused by the weight deflection of the substrate becomes the largest near the center of the substrate, so it can be considered that the distance from the center point of the film surface (the main surface of the substrate) to the reference plane becomes closest to the outer edge of the substrate from the reference plane The flatness is the smallest at the distance. When measuring the distance between the outer edge of the substrate and the reference plane, a plurality of measurement points can be set on the outer edge, or a specific position can be set as a representative point. In addition, the vacuum pressure when the flatness of the film surface becomes the minimum can be measured by actually setting the substrate in an exposure device, or it can be obtained as a part of the simulation using the information related to the holding state.

Secondly, the prepared model conditions are inputted into the software of the finite element method (FEM), and the above-mentioned forced shift is used to estimate what kind of shift is performed at each measurement point other than the holding point. Thereby, "transfer surface shape data C" which shows the film surface shape of the mask in an exposure apparatus can be obtained.

When applying the finite element method, various physical property values or conditions are required. In this embodiment, the following is taken as an example.

[Physical property conditions of substrate (quartz glass)]

Young's modulus E: 7341kg / mm ²

Poisson's ratio ν: 0.17

Weight density m: 0.000022 kg / mm ³

[Mask Model conditions]

File of coordinate values (x, y, z) of each measurement point: (about all measurement points on the film surface, back, and intermediate points)

Condition file linking measurement points: hexahedron

In this form, the hexahedral integration model is created by connecting all adjacent neighbors to the corresponding measurement points on the film surface and the back, and the intermediate points (including the virtual measurement points) (see Figure 7).

[Maintaining conditions]

File for setting the forced shift amount: the forced shift amount of the above holding point

[Vacuum pressure conditions]

A file that sets the amount of vacuum pressure and the area where the vacuum pressure is applied

Then, the amount of shift of all measurement points except the holding point was calculated by the finite element method.

The mask held in the exposure device is stationary by the balance of the force acting on it. This holds: the weight vector G-stress vector σ-vacuum pressure vector f = 0.

Here, the stress vector σ = [k] × shift vector u

(Where [k] is a matrix composed of Young's modulus e and Poisson's ratio ν)

Self-weight vector G = element volume × weight density m × gravity direction vector.

Here, as shown in FIG. 7, each element is a respective hexahedron.

If this hexahedron is superimposed for all elements (the entire substrate), G1-σ1-f1 + G2-σ2-f2 + G3-σ3-f3 + ... = 0 (formula <1>)

G1-f1 + G2-f2 + G3-f3 + ... = σ1 + σ2 + σ3 + ... = [k1] u1 + [k2] u2 + [k3] u3 + ... (Eq. <2>)

Here, the shift amount vectors (u1, u2, u3,...) Are shift amounts of the respective measurement points, and are numerical values to be obtained. However, the shift amount vector of the hold point is input as the forced shift amount as described above.

Data on the shape of the film surface of the mask held in the exposure device is obtained based on the displacement amount vectors of the respective measurement points calculated by the above-mentioned finite element method. That is, the data is data of the shape of the film surface of the mask when the pattern transfer is completed by the exposure device, and is "transfer surface shape data C".

III-2 Method <2>

In mode <2>, the model of FIG. 13 is used.

Here, as shown in FIG. 13 (b), the holding members of the exposure device are in contact with the vicinity of the two opposite sides of the main surface of the photomask substrate (the measurement points on the dotted line in FIG. 13 (b) become the holding points). ). Then, hold the photomask with the film surface side facing downward. The main plane of the mask substrate in the exposure machine is forcibly shifted by its holding point being restricted by the holding member, so that the displacement affects the entire shape of the film surface due to the physical properties of the substrate.

The model shown in FIG. 13 (a) sets the amount of forced shift so that the position of the measurement point that becomes the holding point becomes zero on the Z axis. Moreover, the zero position in the Z-axis direction refers to the least square plane that has been set (and the origin above it). For example, if the value of the flatness of the film surface side at a certain measurement point which is a holding point is 5 μm, the forced shift amount of the measurement point becomes “−5 μm”.

Next, input the model conditions prepared above into the software of the finite element method (FEM), and estimate what kind of shift each measurement point other than the holding point is made by the aforementioned forced shift. Thereby, "transfer surface shape data C" which shows the film surface shape of the mask in an exposure apparatus can be obtained. The transfer surface shape data C includes a deflection component due to gravity (see FIG. 14 (b)).

When applying the finite element method, various physical property values or conditions are required. However, this method does not apply vacuum pressure to the photomask substrate provided in the exposure apparatus. Therefore, there is no need to set a file with vacuum pressure conditions in the above method <1>.

Here, as shown in FIG. 7, each element is a hexahedron.

The sum of all six elements (the entire substrate) is: G1-σ1 + G2-σ2 + G3-σ3 + ... = 0 (formula <3>)

G1 + G2 + G3 + ... = σ1 + σ2 + σ3 + ... = [k1] u1 + [k2] u2 + [k3] u3 + ... (Eq. <4>)

Here, the shift amount vectors (u1, u2, u3,...) Are shift amounts of the respective measurement points, and are values to be obtained. However, the vector of the amount of shift of the hold point is enforced as described above. Enter the shift amount.

The data of the shape of the film surface of the photomask held in the exposure device is obtained by using the displacement amount vectors of the respective measurement points calculated by the above-mentioned finite element method. That is, the data is data of the shape of the film surface of the mask when the pattern transfer is completed by the exposure device, and is "transfer surface shape data C".

Steps to obtain transfer surface correction data D

The transfer surface shape data C includes the influence of deflection caused by the gravity acting on the substrate. On the other hand, the deformation of the shape of the film surface caused by the deflection by its own weight, and then the displacement of the coordinate positions caused by the deformation, can be provided by the size of the substrate or the physical properties of the material. It is relatively easy to estimate. Therefore, in the exposure device used in the manufacture of a photomask for a display device, there is a person who has a function of correcting the deviation of the coordinates originating from the self-deflection component. In this case, the self-deflection component is compensated for drawing.

Therefore, in order to obtain the drawing correction pattern data, it is necessary to remove the gravity deflection component from the "transfer surface shape data C" in a manner that does not duplicate the correction using the compensation function of the gravity deflection component provided by the exposure device. . Therefore, the transfer surface correction data D obtained by subtracting the amount of deformation due to the self-deflection of the substrate from the transfer surface shape data C, that is, the self-deflection component, is obtained (FIG. 14 (e)).

Therefore, the deformation component due to self-deflection (self-deflection component) is estimated. That is, for a substrate (also referred to as an ideal substrate) of the same material, shape, size, and ideal shape (the ideal plane whose principal planes are parallel to each other) as the above-mentioned substrate, the deformation caused by the gravity deflection of the principal surface ( Figure 14 (d)). This deformation is also referred to as reference shape data C1. Here, the finite element method can be applied in the same manner as described above.

Alternatively, instead of obtaining a gravity deflection component of a hypothetical ideal substrate, a specific reference substrate may be prepared, and the deformation caused by self-deflection of the substrate may be determined by the sequence of the above-mentioned finite element method. The reference shape data C2 obtained in this case may be used instead of C1. When the specifications of the reference substrate have been determined relative to the specific exposure device This method can be applied. The C1 or C2 is equivalent to the weight-deformation amount data R indicating the amount of deformation of the main surface caused by the deflection of the main surface of the main surface among the deformations of the main surface generated when the substrate is held in the exposure device.

Furthermore, if C1 (or C2) is subtracted from the previously obtained transfer surface shape data C to obtain a difference, transfer surface correction data D can be obtained (FIG. 14 (e)).

IV. Steps to Obtain the Difference Data F

As described above, when a pattern is drawn on the photomask base by the drawing device, the photomask base is placed on the table of the drawing device with the film surface facing upward. At this time, the following four deformation factors can be considered among the deformation factors of the surface shape of the film surface of the mask base from the ideal plane.

(1) Insufficient flatness of the workbench; (2) Deflection of the substrate due to foreign objects sandwiched on the workbench; (3) Concavity and convexity of the base film surface of the photomask; and (4) The deformation of the film surface caused by the unevenness on the back surface; therefore, the surface shape of the mask base in this state is formed by the accumulation of the above-mentioned four deformation factors. Then, the mask base in this state is drawn.

On the other hand, patterning is performed after drawing, and on the main surface of the photomask provided in the exposure device, the above-mentioned deformation factors (1), (2), and (4) disappear. The degree of coordinate shift due to this shape change needs to be quantified.

Here, the deformation factor of the above (1) is inherent to the worktable of the drawing device, and is a coordinate offset element that is reproducible as long as the same worktable is used. Therefore, the shape of the table surface of the drawing device can be accurately measured in advance and retained as a parameter. This parameter is used when obtaining the drawing difference data F described below. This parameter is, for example, the coordinate offset specific data Q.

In addition, the above-mentioned deformation factor (2) is an occasional coordinate shift factor, and the probability of occurrence is not large. Furthermore, in order to further reduce the occurrence of coordinate shifts caused by this factor, The cleaning step of the workbench is carried out to prevent the existence of foreign objects as much as possible.

In other words, the height variation on the drawing table caused by the above-mentioned deformation factors (3) + (4) can be set to (3) + (substrate thickness variation). That is, for the deformation factor (4) among the factors affecting the coordinate shift, the value of the thickness distribution data T can be used for data correction.

Therefore, in the present invention, the step of obtaining the drawing difference data F can be performed using the thickness distribution data T and the transfer surface shape data C obtained in advance.

In the case of mode <1> (Fig. 8): As shown in Fig. 8, the difference between the transfer surface shape data C and the thickness distribution data T is obtained. Preferably, the drawing difference data F is obtained by further subtracting the coordinate offset specific data Q indicating a coordinate offset element unique to the drawing device such as the flatness of the table from the difference obtained here. In addition, the coordinate offset inherent data Q may be converted into the XY coordinate value in the form of a coordinate offset, and then reflected in the drawing coordinate offset data G.

Case of Mode <2> (Figures 14, 15)

As shown in FIG. 15, the difference between the transfer surface correction data D and the thickness distribution data T is obtained, and thereby the drawing difference data F is obtained. Preferably, the coordinate difference inherent data Q is further subtracted from the difference obtained here to obtain the drawing difference data F. In addition, the coordinate offset inherent data Q may be converted into the XY coordinate value in the form of a coordinate offset, and then reflected in the drawing coordinate offset data G.

On the other hand, the deformation factor from the ideal plane of the film surface of the photomask held in the exposure device is the cumulative result of the three deformation factors described below.

(5) unevenness of the film surface of the photomask (substantially the same as (3) above); (6) deformation of the film surface forcibly caused by being held by the photomask holding member; and (7) caused by self-weight Deflection (in the case of applying a vacuum pressure in order to reduce the deflection, the deformation in the opposite direction caused by the vacuum pressure)

Therefore, the difference between the shapes of the two films is a factor that causes the coordinate shift caused by the transfer, so it can be said that it should be applied to the correction of "pattern design data A" By. That is, the difference is the drawing difference data F described above.

V Steps to obtain coordinate offset data G for drawing

The drawing difference data F is converted into a shift (coordinate offset) on the XY coordinates. For example, conversion can be performed by the following method (refer to FIG. 9).

FIG. 9 is an enlarged view depicting a cross section of a substrate (mask base) 13 on a table 10 of the apparatus. The thin film 14 is omitted. As described above, the shape of the surface 20 of the substrate 13 disposed on the table 10 becomes a person deformed from an ideal plane due to a plurality of factors.

Here, when the height of a measurement point adjacent to a measurement point of height 0 (that is, a measurement point whose height coincides with the reference surface 21) is H, the surface 20 of the substrate 13 and the reference are caused by the difference in height. The angle Φ of the angle formed by the surface 21 is expressed by the following formula: sinΦ = H / Pitch ... (Equation 1)

(Pitch: The distance between the measurement points, that is, the distance P from the adjacent measurement points).

Furthermore, in the above, H / Pitch can also be considered as a gradient in the height direction of the substrate surface.

In addition, if the value of Φ is sufficiently small, it can also be approximated as: Φ = H / Pitch ... (Equation 1 ').

In the following description, (Expression 1) is used.

In the above case, the offset d in the X-axis direction of the measurement point due to the difference in height can be obtained by the following formula: d = sinΦ × t / 2 = H × (t / 2Pitch) ... 2).

Moreover, in the above, if Φ is sufficiently small, it can also be approximated as: d = Φ × t / 2 = H × (t / 2Pitch)... (Expression 2 ′).

Alternatively, the coordinate offset of the measurement point due to the difference in height can also be calculated by a method using a vector. FIG. 12 is a graph showing coordinate deviations of measurement points due to height differences as vectors. In the height distribution data E at the time of drawing, consider from any three parts An inclined surface made by measuring points. At this time, the deviation ΔX of the inclined surface from the X-axis direction and the deviation ΔY of the inclined surface from the Y-axis direction are expressed by the following formula.

△ X = t / 2 × cosθx △ Y = t / 2 × cosθy …… (Equation 3)

Two tilt vectors can be created from measurement points at any of three locations. A normal vector with respect to the inclined plane is generated based on the outer product calculation of the two inclined vectors.

Furthermore, cosθx is calculated from the inner product calculation of the normal vector and the X-axis unit vector, and cosθy is calculated from the inner product calculation of the normal vector and the Y-axis unit vector.

The calculated cosθx and cosθy can be substituted into (Expression 3) to finally calculate the offset ΔX in the X-axis direction and the offset ΔY in the Y-axis direction.

Here, t is the thickness of the substrate. The thickness t of each measurement point is included in the TTV already obtained in the above.

Therefore, in this form, all the measurement points on the substrate 13 are calculated to be equivalent to the transfer surface shape data C (in the method <2>, the transfer surface correction data D obtained by subtracting the gravity deflection component from the transfer surface shape data C ) And the height of the thickness distribution data T, and calculate the coordinate offset of the obtained drawing difference data F in the X direction and the Y direction, thereby obtaining the drawing coordinate offset data G. Of course, as long as the effect of the present invention is not impaired, the calculation method is not limited to the above.

VI Drawing step of drawing correction pattern data H

Using the obtained coordinate offset data G for drawing and "pattern design data A", the drawing of the correction pattern data H is performed.

At this time, the drawing design pattern data H (not shown) may be obtained by correcting the pattern design data A based on the drawing coordinate offset data G, and drawing may be performed based on the drawing correction pattern data H.

When the pattern design data A is corrected, the drawing coordinate offset data G obtained for each measurement point may be processed and used. For example, you can use The method interpolates data for each measurement point or standardizes it with a specific rule, and then makes the coordinate offset data G for drawing reflect on the pattern design data A.

Alternatively, the coordinate system included in the drawing device may be modified based on the coordinate offset data G for drawing, and the obtained corrected coordinate system and the "pattern design data A" may be used for drawing. The reason for this is that many drawing devices have a function of making a specific correction to the coordinate system that they have, and drawing based on the corrected coordinate system.

The coordinate offset data G for drawing used at this time may be processed in the same manner as described above.

It should be noted that the drawing method of the present invention is not limited to the aforementioned form.

When performing drawing, a marking pattern or the like may be appropriately provided in addition to the pattern area for transfer. As described below, a marker pattern for coordinate measurement may be additionally drawn here.

For example, as described above, the shape of the holding member of the exposure device may vary depending on the device.

In the method <1>, an exposure apparatus provided with four linear holding members along four sides of the substrate is exemplified.

In mode <2>, the case where the holding member arrange | positioned in parallel in the vicinity of two opposite sides of a board | substrate and the film surface side of a board | substrate is demonstrated.

However, the present invention can also be applied to a device having the shape of another member. In this case, it is only necessary to change the conditions as appropriate when the model conditions, holding conditions, and vacuum pressure conditions are provided when calculating the above-mentioned finite element method.

Moreover, in the said form, the holding | maintenance point which hold | maintains a photomask to a holding | maintenance member is set to the plane (the least square plane of a substrate film surface). In this process, the holding member holds the photomask on a single plane. However, when the holding point cannot be mounted on a single plane due to the shape of the holding member, it is only necessary to reflect the shape of the holding member when setting the forced displacement amount in the step of obtaining the transfer surface shape data C.

In addition, the order of the steps may be changed as long as it does not hinder the effect of the present invention. In addition, even if the order of operations is changed, the case where the result does not change is of course included in the present invention. Bright.

After drawing the corrected pattern data on the photomask base by the drawing method of the above-mentioned form, a photomask is manufactured through a patterning process.

About the patterning process

The mask base (mask semi-finished product) that has been drawn is converted into a mask through the following steps.

For the patterning process, a known method can be applied. That is, the photoresist film on which drawing has been performed is developed by a known developer to form a photoresist pattern. The photoresist pattern can be used as an etching mask to etch a thin film.

As the etching method, a known one can be used. Either dry etching or wet etching can be applied. The present invention is particularly useful as a method for manufacturing a photomask for a display device. Therefore, when wet etching is applied, the effect of the present invention can be remarkably obtained.

In addition, with regard to the drawing steps of the present invention described above, the subject of the drawing is not only the photomask base (those who have not drawn the pattern for transfer), but also a plurality of films with a pattern formed on a part thereof Photomask semi-finished products.

The above-described drawing step of the present invention can be applied to a mask substrate having a plurality of films in the drawing step for patterning each film. In this case, it is extremely advantageous in that a high-precision photomask having excellent overlap accuracy can be manufactured.

Drawing device

Furthermore, this application contains the invention regarding the drawing apparatus which can implement the drawing method as mentioned above.

That is, the drawing device is a drawing device for drawing a transfer pattern on a mask base having a thin film and a photoresist film formed on a main surface of a substrate.

The drawing device includes the following mechanisms.

Input mechanism

The input mechanism is as follows: the pattern design information of the above-mentioned transfer pattern can be input Material A, Thickness distribution data T indicating the thickness distribution of the substrate, and transfer surface shape data C indicating the main surface shape of the substrate in a state where the substrate is held in an exposure device.

Computing mechanism

The arithmetic unit calculates the coordinate offset data G for drawing a plurality of points on the main surface using the thickness distribution data T and the transfer surface shape data C.

The drawing device includes a drawing mechanism for drawing on the mask base using the drawing coordinate offset data G and the pattern design data A.

Furthermore, the drawing device of the present invention may include the following means.

Input mechanism

The input mechanism is a mechanism that can input the pattern design data A of the transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and the substrate surface shape data B indicating the shape of the main surface of the substrate, and Information related to the holding state when the substrate is held in the exposure device, and substrate information including physical property values of the substrate material.

Computing mechanism

The calculation mechanism is a mechanism that can use the substrate surface shape data B, the information related to the holding state, and the substrate information to calculate the transfer surface shape data indicating the main surface shape of the substrate held in the exposure device. C, and the above-mentioned thickness distribution data T and the transfer surface shape data C may be used to calculate the coordinate offset data G for drawing a plurality of points on the main surface. As the computing means, for example, a known computing device such as a personal computer can be used.

Drawing agency

The drawing mechanism is a mechanism for drawing on the mask base using the drawing coordinate offset data G and the pattern design data A.

Moreover, it is preferable that the drawing device includes a control unit that controls the input mechanism, the calculation unit, and the drawing unit.

Here, the information about the holding state preferably includes, for example, the holding conditions (the shape of the holding member, or the coordinates of the substrate holding point where the substrate is in contact with the holding member when the substrate is held in the exposure device) (may be based on the coordinates The information estimates the forced displacement amount of the holding point)), and further includes information about vacuum pressure conditions (amount of vacuum pressure and applied area) when a vacuum pressure is used.

The substrate information may be, for example, information indicating Young's modulus, Poisson's ratio, and weight density of the substrate.

By using such a drawing device, the drawing steps required for the mask manufacturing method described above can be performed.

<Embodiment 2> (Inspection)

As described above, according to the present invention, it is possible to obtain a photomask capable of making the accuracy of the coordinates of a pattern formed on an object to be extremely high.

In addition, when inspecting such a photomask before shipment, it is most desirable to perform an inspection considering the difference between the photomask placed in the inspection device and the photomask held in the exposure device.

Therefore, the necessity of a new inspection method was discovered by the inventors.

VII Steps to obtain pattern coordinate data L

The film surface (pattern-forming surface) is set to the upper side, and the patterned mask is placed on the table of a coordinate inspection device to measure the coordinates of the pattern for transfer. Let the data obtained here be pattern coordinate data L.

Here, the coordinate measurement is preferably performed by measuring the coordinates of a mark pattern formed on the main surface of the photomask simultaneously with the pattern for transfer. The markup It is preferable to provide a plurality of positions on the main surface and outside the area of the pattern for transfer.

VIII Preparation of thickness distribution data T indicating the thickness distribution of the above substrate

In this step, the thickness distribution data T can be obtained in the same manner as the step described in the second embodiment of the first embodiment.

IX Steps to obtain the transfer surface shape data C

The transfer surface shape data C can be obtained in the same manner as described in the above-mentioned embodiment III.

X Steps to Obtain Difference Data J

The inspection difference data J is obtained by finding the difference between the thickness distribution data T and the transfer surface shape data C (see FIGS. 10 (a) to (d)).

Preferably, the difference obtained here is further subtracted from the coordinate offset component S inherent in the inspection device such as the flatness of the table surface, that is, the inspection coordinate offset constant data S.

XI Steps to Obtain Coordinate Offset Data K for Inspection

The coordinate offsets K for inspection are estimated by estimating the coordinate offsets of a plurality of points on the main surface corresponding to the inspection difference data J (see FIGS. 10 (d) to (e)). Here, the step of converting the difference in height to the coordinate offset can be performed in the same manner as the step of V described above.

Further, in the inspection step, the inspection pattern for transfer is inspected using the obtained inspection coordinate offset data K and the pattern coordinate data L.

Specifically, the inspection of the transfer pattern can be performed (comparison) using the corrected design data M and the pattern coordinate data L obtained by reflecting the inspection coordinate offset data K on the pattern design data A.

Alternatively, the inspection of the transfer pattern may be performed (compared) using the corrected coordinate data N obtained by reflecting the inspection coordinate offset data K on the pattern coordinate data L and the pattern design data A.

It is preferable to inspect the photomask manufactured by the manufacturing method of this invention by the inspection method of this invention.

Furthermore, the use of the photomask is not limited, and its composition is also not limited.

It is clear that the action and effect of the present invention can be obtained in a mask having any one of a film structure such as a so-called binary mask, a multi-gray scale mask, and a phase shift mask.

Inspection device

Moreover, this invention includes the invention regarding the inspection apparatus which can implement the inspection method as mentioned above.

In other words, a photomask inspection device for inspecting a photomask having a pattern for transferring a film formed on a main surface of a substrate, and having a coordinate measuring mechanism formed on the main surface. The pattern coordinate data L is obtained by measuring the coordinates of the above-mentioned transfer pattern; the input means inputs the pattern design data A of the above-mentioned transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and indicates that the substrate is held at The transfer surface shape data C of the main surface shape of the substrate in the state of the exposure device; a calculation mechanism that uses the thickness distribution data T and the transfer surface shape data C to calculate the coordinate deviations of the plurality of points on the main surface for inspection A shift amount data K; and an inspection mechanism that uses the above-mentioned inspection coordinate shift amount data K and pattern design data A to inspect the transfer pattern of the photomask.

Furthermore, the present invention includes the following inspection devices.

An inspection device is a mask inspection device for inspecting a mask having a pattern for transferring a pattern formed on a main surface of a substrate, and the inspection device includes a coordinate measuring mechanism formed on the substrate. The pattern coordinate data L is obtained by measuring the coordinates of the above-mentioned transfer pattern on the main surface; the input mechanism inputs the pattern design data A, Thickness distribution data T indicating the thickness distribution of the substrate, substrate surface shape data B indicating the shape of the main surface of the substrate, information related to the holding state when the substrate is held in an exposure device, and physical properties including the substrate material Value substrate information; an arithmetic unit that can use the substrate surface shape data B, the information related to the holding state, and the substrate information to calculate the transfer surface shape of the main surface shape of the substrate that is held in the exposure device Data C, and using the thickness distribution data T and the transfer surface shape data C to calculate the inspection coordinate offset data K of a plurality of points on the main surface; and an inspection mechanism using the inspection coordinate offset Document K and the pattern design document A are used to check the pattern for transfer of the photomask.

The information related to the holding state when the substrate is held in the exposure apparatus and the substrate information including the physical property values of the substrate material are as described above.

The transfer surface shape data C of the main surface shape of the above-mentioned substrate, which indicates the state of being held in the exposure device, is an operation for performing the same steps as those of the above-mentioned steps III-1 to III-2.

When using the above-mentioned inspection coordinate offset data K and the above-mentioned pattern design data A to check the transfer pattern of the photomask, perform the comparison required for the above-mentioned step XI (if necessary, perform the calculation for comparison) ).

Manufacturing method of display device

The present invention relates to a method for manufacturing a display device including pattern-transferring a device substrate having a processed layer by exposing a photomask having a pattern for transfer formed on a main surface thereof, and including using the light of the present invention. Manufacturing method of cover manufacturing method of display device of photomask.

That is, a method for manufacturing a display device uses a photomask manufactured by the manufacturing method of the present invention, and applies the following pattern transfer method when manufacturing the photomask, that is, using The exposure is performed using the exposure device that has determined conditions for the state held in the exposure device. The pattern transferred to the object by pattern transfer is a display device by performing processing such as etching.

Here, as the optical performance possessed by the exposure device, for example, the effect of the present invention is significant when it is as follows.

An exposure device used for equal exposure of LCD (or FPD (Flat Panel Display, flat panel display), liquid crystal) exposure, its composition is as follows: the numerical aperture (NA) of the optical system is 0.08 ~ 0.15 (especially 0.08 ~ 0.10); coherence factor (σ) is 0.5 ~ 0.9; exposure light is any one of i-ray, h-ray, and g-ray as the representative wavelength of exposure light, particularly preferably including all of i-ray, h-ray, and g-ray Wide wavelength light source.

Furthermore, when a vacuum pressure is applied, it is preferably applied to the vacuum pressure applied in the above-mentioned finite element method when the exposure device is provided with a photomask.

The layer to be processed refers to each layer which becomes a structure of a desired electronic device after a process such as etching after the transfer pattern of the photomask is transferred. For example, when forming a TFT (Thin Film Transistor) circuit for driving a liquid crystal display device or an organic EL display device, a pixel layer, a source / drain layer, and the like can be exemplified.

The device substrate refers to a substrate having a circuit that becomes a constituent of an electronic device to be obtained, such as a liquid crystal panel substrate and an organic EL panel substrate.

Furthermore, the present invention relates to a display device including the above-mentioned exposure device and a plurality of photomasks formed with a transfer pattern formed on a main surface of each of the display devices. The manufacturing method includes using a photomask manufactured by the manufacturing method of the present invention.

The display device manufactured by applying the present invention has extremely high overlap (overlay) accuracy of each layer constituting the display device. Therefore, the manufacturing yield of the display device is higher and the manufacturing efficiency is higher.

[Example]

The effect of the invention using the manufacturing method (drawing step) of the photomask of the present invention will be described using the schematic diagram shown in FIG. 17.

Here, the results are shown below. When a transfer pattern is drawn on a substrate (mask base) having a specific substrate surface shape (substrate surface shape data B), the result is obtained by simulation in an exposure device. What is the accuracy of the coordinate accuracy of the pattern for transfer (what accuracy of the coordinate accuracy of the pattern finally formed on the object to be transferred).

First, use a drawing device to draw a specific test pattern on the photomask substrate. The mask base for testing used here is a case where a light-shielding film and a positive-type photoresist film are formed on the main surface of a quartz substrate having a size of 850 mm × 1200 mm.

As the pattern design data used herein, a test pattern including a cross pattern arranged on the substantially entire surface of the main surface at intervals of 75 mm in the X and Y directions was set. Then, the photoresist is developed, and the light-shielding film is subjected to wet etching, thereby obtaining a test mask having a light-shielding film pattern. This test mask was set in a coordinate inspection device and coordinate measurement was performed. The result is shown in FIG. 17 (a).

In addition, the factor of the coordinate shift caused by the flatness of the table of the drawing device and the flatness of the table of the coordinate checking device is determined from the flatness of the table of the two devices in advance from FIG. 17 (a). Removal of data.

Next, the coordinate deviation in a state where the test mask is set in an exposure device (equal-magnitude projection exposure method) is simulated. Here, using the exposure device of the above-mentioned method <1>, using the shape information, vacuum pressure conditions, and substrate physical property information of the mask holding member of the exposure device, using the finite element method to estimate the coordinate offset generated by the test pattern, and obtained Figure 17 (b) (comparative example).

On the other hand, when drawing the same test pattern on the photomask base, the coordinates of the drawing machine are corrected to draw pattern design data. When the coordinate system is corrected, the coordinate offset data for drawing is obtained by the steps of II to V described above. Fig. 17 (c) shows the result of measuring the coordinates obtained by setting the test mask obtained by this result on the coordinate inspection device. fruit.

Next, a coordinate shift in a state where the test mask obtained from the result is set in an exposure device is simulated in the same manner as described above. The simulation results are shown in Fig. 17 (d) (Example).

According to FIG. 17 (d), it can be seen that compared with FIG. 17 (b), a transfer image closer to the pattern design data can be obtained on the object to be transferred. In the photomask manufactured by the method of the present invention, the accuracy of the coordinates is high, and the error value of the coordinates can be suppressed to less than 0.15 μm. That is, it can be set to an accuracy that is substantially excluding an error component other than a coordinate shift caused by the ability of the drawing device.

Claims (25)

A manufacturing method of a photomask, which includes a photomask base on which a thin film and a photoresist film are formed on a main surface of a substrate, and draws a specific transfer pattern by a drawing device, and has the following characteristics: Step of preparing pattern design data to prepare pattern design data A; prepare thickness distribution data T representing the thickness distribution of the substrate; prepare transfer surface shape representing the shape of the main surface when the photomask is held in an exposure device The step of data C is a step of obtaining the drawing difference data F by using the thickness distribution data T and the transfer surface shape data C; estimating the coordinate offsets of a plurality of points on the main surface corresponding to the drawing difference data F and A step of obtaining the coordinate offset data G for drawing; and a drawing step of drawing on the mask base using the coordinate offset data G for drawing and the pattern design data A, and the transfer surface shape data C Including deformation of the substrate due to the force with which the substrate is held by the exposure device. A manufacturing method of a photomask, which includes a photomask base on which a thin film and a photoresist film are formed on a main surface of a substrate, and draws a specific transfer pattern by a drawing device, and has the following characteristics: The step of preparing the pattern design data A for the design of the printed pattern; the step of preparing the thickness distribution data T indicating the thickness distribution of the substrate and the substrate surface shape data B indicating the surface shape of the main surface; The displacement in the exposure device caused by the above surface shape The position is reflected on the substrate surface shape data B to obtain the transfer surface shape data C representing the shape of the main surface when held in the exposure device; using the thickness distribution data T and the transfer surface shape data C to obtain a drawing difference Step of data F; step of estimating coordinate offsets of a plurality of points on the main surface corresponding to the above-mentioned drawing difference data F to obtain drawing offset data G; and using the above-mentioned drawing offsets The drawing step of drawing the data G and the above-mentioned pattern design data A on the mask substrate. For example, the method for manufacturing a photomask according to claim 1 or 2, wherein the deformation amount of the main surface caused by the weight deflection of the substrate among the deformations of the main surface generated when the substrate is held in the exposure device is obtained. For the weight deformation amount data R, in the step of obtaining the drawing difference data F, the thickness distribution data T, the transfer surface shape data C, and the weight deformation amount data R are used. For example, the manufacturing method of the photomask of claim 2, wherein the above-mentioned substrate surface shape data B is to maintain the state of the photomask base or the substrate used to make the photomask base in such a manner that the main surface becomes substantially vertical. Next, the positions of the plurality of measurement points on the main surface are measured and determined. For example, the manufacturing method of the photomask of claim 1 or 2, wherein the thickness distribution data T is obtained by: holding the photomask base or the substrate used to make the photomask base in such a manner that the main surface becomes substantially vertical. In a state, the positions of a plurality of measurement points on the main surface are measured and determined. For example, if the manufacturing method of the photomask of claim 1 or 2 is obtained, the coordinate offset inherent data Q related to the coordinate offset component inherent to the drawing device is obtained in advance, and in the above drawing step, the above-mentioned drawing coordinate offset is used The data G, the pattern design data A, and the coordinate offset specific data Q are drawn on the mask base. For example, the method for manufacturing a photomask according to claim 1 or 2, wherein a finite element method is used in the step of obtaining the above-mentioned transfer surface shape data C. The method for manufacturing a photomask according to claim 1 or 2, wherein in the above-mentioned drawing step, drawing is performed using the correction pattern data H obtained by correcting the above-mentioned pattern design data A based on the above-mentioned drawing coordinate offset data G. For example, the manufacturing method of the photomask of claim 1 or 2, wherein in the drawing step, the coordinate system of the drawing device is modified based on the drawing coordinate offset data G, and the obtained corrected coordinate system and the pattern are used Design data A and draw. For example, the method for manufacturing a photomask according to claim 1 or 2, wherein when the photomask is held in the exposure device, a plurality of holding points held by the holding member are arranged on a plane. A drawing device is used for drawing a pattern for a transfer on a mask base having a thin film and a photoresist film formed on a main surface of a substrate, and has an input mechanism for inputting pattern design information of the above-mentioned pattern for transfer. A, thickness distribution data T indicating the thickness distribution of the substrate, substrate surface shape data B indicating the shape of the main surface of the substrate, information related to the holding state when the substrate is held in an exposure device, and materials including the substrate Substrate information of physical properties; an arithmetic unit that can calculate the main surface shape of the substrate indicated by the state held in the exposure device using the substrate surface shape data B, the information related to the holding state, and the substrate information. Transfer surface shape data C, and use the thickness distribution data T and the transfer surface shape data C to calculate coordinate drawing offset data G for a plurality of points on the main surface; and a drawing mechanism using the drawing coordinates The offset data G and the pattern design data A are drawn on the photomask base. If the drawing device of claim 11 is further provided with a memory mechanism, the memory mechanism is guaranteed The weight deformation amount data R indicating the deformation amount of the main surface caused by the weight deflection of the substrate among the deformations of the main surface generated when the substrate is held in the exposure device is stored, and the calculation mechanism uses the weight deformation The quantity data R is calculated. For example, if the drawing device of claim 11 or 12 has a memory mechanism that stores coordinate offset unique data Q related to the coordinate offset component inherent to the drawing device, and the arithmetic unit uses the coordinate offset unique data Q to perform calculations . A photomask inspection method for inspecting a photomask having a pattern for transferring a film patterned on a main surface of a substrate using an inspection device, and the method includes: placing the photomask on the inspection In the state of the device on the table, the step of measuring the coordinates of the transfer pattern formed on the main surface to obtain the pattern coordinate data L; preparing the thickness distribution data T indicating the thickness distribution of the substrate; obtaining the expression The step of transferring the surface shape data C of the shape of the main surface when the mask is held in the exposure device; the step of obtaining the difference data J using the thickness distribution data T and the transfer surface shape data C; the estimation and the inspection The step of obtaining the coordinate offset data K for inspection by the coordinate offsets of a plurality of points on the main surface corresponding to the difference data J; and using the above-mentioned coordinate offset data K for inspection and the above-mentioned pattern coordinate data L The inspection procedure of the above-mentioned inspection of the transfer pattern is performed. A photomask inspection method for inspecting a photomask having a pattern for transferring a film patterned on a main surface of a substrate using an inspection device, and the method includes: placing the photomask on the inspection With the device on the workbench, Measuring the coordinates of the transfer pattern formed on the main surface to obtain pattern coordinate data L; preparing thickness distribution data T indicating the thickness distribution of the substrate; and substrate surface shape data indicating the surface shape of the main surface Step B; the displacement of the surface shape when the photomask is held in the exposure device is reflected in the substrate surface shape data B, and a transfer surface shape indicating the shape of the main surface when held in the exposure device is obtained Step of data C; step of obtaining inspection difference data J using the thickness distribution data T and the transfer surface shape data C; estimating the coordinate offsets of a plurality of points on the main surface corresponding to the inspection difference data J and A step of obtaining the inspection coordinate offset data K; and an inspection step of performing the inspection of the transfer pattern using the inspection coordinate offset data K and the pattern coordinate data L. If the inspection method of the photomask of claim 14 or 15 is requested, the deformation of the main surface caused by the deflection of the weight of the substrate among the deformations of the main surface that are generated when the substrate is held in the exposure device is obtained. In the step of obtaining the inspection difference data J, the thickness distribution data T, the transfer surface shape data C, and the dead weight deformation amount data R are used. For example, if the inspection method of the photomask of item 14 or 15 is requested, the inspection coordinate offset constant data S related to the coordinate offset component inherent to the inspection device is obtained in advance, and in the inspection step described above, the inspection coordinate offset is used. The transfer pattern K, the pattern coordinate data L, and the inspection coordinate offset constant data S are used to inspect the transfer pattern. For example, the inspection method for a photomask according to claim 15, wherein the finite element method is used in the step of obtaining the transfer surface shape data C described above. If the inspection method of the photomask of item 14 or 15 is requested, the inspection of the above-mentioned transfer pattern The search is performed using the revised design data M obtained by reflecting the above-mentioned inspection coordinate offset data K on the pattern design data A and the above-mentioned pattern coordinate data L. For example, the inspection method of the photomask of claim 14 or 15, wherein the inspection of the transfer pattern is performed by using the corrected coordinate data N and the pattern obtained by reflecting the inspection coordinate offset data K on the pattern coordinate data L. Design data A. A method for manufacturing a photomask, comprising: a step of preparing a photomask substrate having a thin film and a photoresist film formed on a main surface; a step of patterning the thin film; and using a photomask according to claim 14 or 15 Inspection method inspection steps. A manufacturing method of a display device, comprising: preparing a photomask having a pattern for transfer formed on a main surface and manufacturing the photomask by a manufacturing method such as claim 1 or 2; and exposing the photomask The pattern transfer step is performed on the device substrate having the processed layer. A method for manufacturing a display device includes a plurality of photomasks and an exposure device each having a pattern for transferring formed on a main surface thereof, and a pattern transferer sequentially transferring a plurality of processed layers formed on a device substrate , Characterized in that, as the plurality of photomasks described above, a maker manufactured by a photomask manufacturing method such as the item 1 or 2 is used. An inspection device for a photomask, which inspects a photomask having a pattern for transferring a film formed by patterning a film on a main surface of a substrate, and includes a coordinate measuring mechanism that performs the above-mentioned formation on the main surface. The pattern coordinate data L is obtained by measuring the coordinates of the pattern for transfer. The input mechanism inputs the pattern design data A of the transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and indicating that the substrate is held in an exposure device. Main surface of the above substrate Shape transfer surface shape data C; a calculation mechanism that uses the thickness distribution data T and the transfer surface shape data C to calculate coordinate offset data K for inspection of a plurality of points on the main surface; and an inspection mechanism that The pattern for transfer of the photomask is inspected using the inspection coordinate offset data K and the pattern design data A. An inspection device for a photomask, which inspects a photomask having a pattern for transferring a film formed by patterning a film on a main surface of a substrate, and includes a coordinate measuring mechanism that performs the above-mentioned formation on the main surface. The pattern coordinate data L is obtained by measuring the coordinates of the pattern for transfer. The input means inputs the pattern design data A of the transfer pattern, the thickness distribution data T indicating the thickness distribution of the substrate, and the shape of the main surface of the substrate. Substrate surface shape data B, information related to the holding state when the substrate is held in an exposure device, and substrate information including physical property values of the substrate material; a computing mechanism that can use the substrate surface shape data B and the above The transfer surface shape data C indicating the main surface shape of the substrate held in the exposure device is calculated by holding the state-related information and the substrate information, and the above is calculated using the thickness distribution data T and the transfer surface shape data C. Coordinate offset data K of a plurality of points on the main surface for inspection; Transferred to the inspection and inspection of the photomask pattern with offset coordinate information and the pattern design data K A.