WO2014206014A1

WO2014206014A1 - Exposure apparatus, exposure system, and exposure method

Info

Publication number: WO2014206014A1
Application number: PCT/CN2013/088655
Authority: WO
Inventors: 万冀豫; 吴洪江; 黄常刚; 王耸; 张继凯
Original assignee: 京东方科技集团股份有限公司; 北京京东方显示技术有限公司
Priority date: 2013-06-26
Filing date: 2013-12-05
Publication date: 2014-12-31
Also published as: CN103353710A; CN103353710B

Abstract

Disclosed are an exposure apparatus, an exposure system, and an exposure method. The exposure apparatus comprises a light source system, used for providing exposure light for a to-be-exposed substrate (8). The provided exposure light is scattered light, and is emitted to the to-be-exposed substrate (8) through a mask plate (6), so as to photoetch a pattern on the mask plate (6) to the to-be-exposed substrate (8). Therefore, the problem that an offset exists in a size of an exposed graphic on the substrate caused by the fact that the mask plate is deformed in a process of producing a substrate of a large-size liquid crystal display apparatus is solved, thereby ensuring accuracy of key sizes of the graphic on the substrate, and further improving display performance of the liquid crystal display apparatus.

Description

Exposure device, exposure system and exposure method

The present invention relates to an exposure apparatus, an exposure system, and an exposure method. Background technique

With the development of liquid crystal display technology, liquid crystal display devices are moving toward large size, high resolution, and low cost. In the production process of a liquid crystal display device, it is a very important step to form a pattern of each film layer on the surface of the substrate by photolithography, and the photolithography technique includes exposing the substrate to be exposed by using a mask. 1 is a schematic structural view of a prior art exposure apparatus, and FIG. 2 is a schematic diagram of a prior art exposure light. As shown in FIG. 1 and FIG. 2, light generated by the light source 1 is incident on the first plane mirror 2, and is reflected by the first plane mirror 1. The horizontal light is incident on the fly-eye lens 3, and the light transmitted through the fly-eye lens 3 is incident on the concave mirror 4. The distance between the fly-eye lens 3 and the concave mirror 4 is D, and the light reflected by the concave mirror 4 is incident on the second mirror 5, The light reflected by the two plane mirrors 5 is incident perpendicularly to the mask plate 6, and is incident on the substrate 8 to be exposed through the light-transmitting region of the mask plate 6, and a pattern is formed on the substrate 8 through a developing process.

Since the liquid crystal display device is moving toward a large size, the size of the mask used in the exposure process is also becoming larger and larger, and the problem that the mask is deformed by gravity to affect the size of the exposed pattern becomes more and more obvious. Fig. 3 is a schematic view showing the bending of the mask in the prior art exposure process, and Fig. 4 is a schematic view showing the curved edge region of the mask in the prior art exposure process. As shown in FIG. 3 and FIG. 4, in a small range, the arc of the mask 6 can be approximated as a straight line, and the edge of the mask 6 is enlarged and analyzed, wherein the mask 6 has a second for forming a first pattern 11 of the pattern 7, wherein the first pattern 11 is an opening, BP: the first pattern 11 is a light transmissive area, and the width of the first pattern 11 on the mask sheet 6 is on the glass substrate

The width of the second pattern 7 formed on the 8 is L ₂ , which is the angle between the tangent line of the mask 6 and the horizontal plane in a partial range, and the light 12 emitted from the light source system of the exposure device is perpendicularly incident on the upper surface 9 of the mask 6. When the light 12 is incident on the upper surface 9 of the mask 6, the light 12 is refracted in the mask 6 and incident on the lower surface 10 of the mask 6 having a first pattern 11 for forming the second pattern 7 on the lower surface 10. . Wherein the width of the first graphic 11 The degree is that the width of the second figure 7 is L ₂ . The light is exposed through the first pattern 11 to the glass substrate 8, and then developed and etched to form a second pattern 7 on the glass substrate 8, which is obtained by geometric optics, 1^=*cos.

The inventors have found the following problems in the practice of the present invention: In the fabrication of a large-sized liquid crystal display device, a large-sized mask is required to form a desired pattern. However, during the exposure process, the mask may be bent and deformed due to the influence of gravity. In order to ensure that the width of the second pattern is consistent with the width of the first pattern, the angle between the tangent of the mask and the horizontal plane may be reduced; By extrusion, negative pressure, etc., but these methods can not completely make the mask parallel to the horizontal plane, resulting in a deviation of the second pattern formed on the substrate, resulting in CD (critical Dimension) in liquid crystal display technology. The parameters are not accurate. Summary of the invention

The invention provides an exposure device, an exposure system and an exposure method, which can effectively solve the problem of the dimensional deviation of the exposure pattern on the substrate caused by the bending deformation of the mask during the manufacturing process of the large-size liquid crystal display device substrate, and the key of the substrate graphic is ensured. The dimensional accuracy further improves the display quality of the liquid crystal display device.

In order to achieve the above object, the present invention provides an exposure apparatus, the exposure apparatus comprising: a light source system for providing exposure light to a substrate to be exposed;

The exposure device is characterized in that the exposure light is diffused light, and the diffused light is irradiated onto the substrate to be exposed via the mask to lithographically pattern the mask onto the substrate to be exposed. .

According to some embodiments of the present invention, the diffusion angle of the light irradiated to the edge of the mask by the exposure light depends on the degree of curvature of the mask in a curved state.

Further, if the angle between the tangent at the edge of the mask and the horizontal plane is ", the diffusion angle of the light irradiated to the edge of the mask by the exposure light is satisfied: θ =

2 Further, if the angle between the tangent at any point of the mask and the horizontal plane is, the diffusion angle of the light irradiated to the mask at any point of the mask is satisfied: Optionally, the light source system includes a light source, a first plane mirror, a fly-eye lens, a concave mirror and a second plane mirror, and the light emitted by the light source sequentially passes through the first plane mirror, the fly-eye lens, the concave mirror and the After the second plane mirror is described, the light that is irradiated to the mask is diffused light.

Optionally, the radius of the concave mirror is: the radius of curvature of the concave mirror is _P1 , and the distance between the concave mirror and the fly-eye lens is: the relationship between the three parameters satisfies: d, = D, wherein, A is ^ ¹

2

Optionally, the radius of the concave mirror is equal to the radius of curvature A of the concave mirror. Optionally, the exposure apparatus includes a stage for carrying a substrate to be exposed and a mask holder for carrying a mask.

In order to achieve the above object, the present invention provides an exposure system comprising a mask and an exposure device, wherein the exposure device employs the above exposure device.

In order to achieve the above object, the present invention provides an exposure method, the method comprising: determining a curvature of the mask;

Adjusting a diffusion angle of the exposure light according to the measured curvature of the mask; and exposing the exposure light after the diffusion angle is adjusted to the substrate to be exposed via the mask to lithographically pattern the mask to the to be exposed On the substrate. Optionally, the step of determining the curvature of the mask comprises determining an angle between a tangent at the edge of the mask and a horizontal plane; and the step of adjusting a diffusion angle of the exposure light comprises adjusting exposure light to the mask The angle of diffusion of the light at the edge ^ to meet

Θ

2

Optionally, the step of determining the curvature of the mask comprises determining an angle between a tangent and a horizontal plane at a plurality of points on the mask, calculating an angle between a tangent at a point on the mask and a horizontal plane, or directly measuring the mask. The angle between the tangent and the horizontal plane The step of adjusting the diffusion angle of the exposure light includes adjusting a diffusion angle of the light irradiated to the mask at any point of the exposure light, which satisfies =.

2

Optionally, the radii of the concave mirror, the radius of curvature A of the concave mirror, and the distance between the concave mirror and the fly-eye lens are adjusted according to the following equations: Adjust the diffusion angle d, where D is A

Optionally, the radius of the concave mirror is equal to the radius of curvature A of the concave mirror. In the exposure apparatus, the exposure system, and the exposure method provided by the present invention, the exposure apparatus includes a light source system for providing exposure light to the substrate to be exposed, the exposure light is diffused light; and the exposure light is irradiated to the On the substrate, a pattern of the mask is lithographically patterned onto the substrate. The diffused exposure light provided by the light source system is matched with the mask in a curved state, which can effectively solve the problem of dimensional deviation of the exposed pattern on the substrate caused by the bending deformation of the mask during the manufacturing process of the large-sized liquid crystal display device substrate. The critical dimension accuracy of the substrate pattern is ensured, thereby improving the display quality of the liquid crystal display device. DRAWINGS

1 is a schematic structural view of a prior art exposure apparatus;

2 is a schematic diagram of exposure light of the prior art;

3 is a schematic view showing a bending of a mask in a prior art exposure process;

4 is a schematic view of a curved edge region of a mask in a prior art exposure process; FIG. 5 is a schematic structural view of an exposure device according to a first embodiment of the present invention; FIG.

FIG. 7 is a schematic diagram of a partial area in an exposure process according to Embodiment 1 of the present invention; FIG. 8 is a flowchart of an exposure method according to Embodiment 2 of the present invention; FIG. 9 is an exposure system according to Embodiment 3 of the present invention; Schematic diagram of the structure. detailed description

The technical solutions of the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings. It is apparent that the described embodiments are part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the described embodiments of the present invention without the need for inventive work are within the scope of the present invention. In addition, the drawings are merely schematic views, and the dimensions, thicknesses, heights, and the like of the respective components are not drawn to scale, and the relative positional relationship between the components is not completely consistent with the actual relative positional relationship, The drawings are only used to facilitate the description and explanation of the invention, and are not intended to limit the scope of the invention.

FIG. 5 is a schematic structural diagram of an exposure apparatus according to Embodiment 1 of the present invention. As shown in Figure 5, the exposure apparatus includes a light source system that provides diffused exposure light. The exposure light is irradiated onto the substrate via the mask 6 to lithographically pattern the mask 6 onto the substrate 8. The exposure apparatus further includes a stage (not shown) for carrying the substrate to be exposed and a mask holder (not shown) for carrying the mask.

In the embodiment shown in Fig. 5, the light source system comprises a light source 1, a first plane mirror 2, a fly-eye lens 3, a concave mirror 4 and a second plane mirror 5. The light emitted from the light source 1 passes through the first plane mirror 2, the fly-eye lens 3, the concave mirror 4, and the second plane mirror 5 in order to become a diffused light, and then the substrate 8 is irradiated through the mask 6 to expose the substrate 8. Specifically, the light generated by the light source 1 is incident on the first plane mirror 2, and the light reflected by the first plane mirror 1 is incident on the fly-eye lens 3. The light transmitted through the fly-eye lens 3 is incident on the concave mirror 4, and is reflected by the concave mirror 4. The rear light is incident on the second plane mirror 5, so that the light reflected by the second plane mirror 5 is incident on the mask 6, and the exposure light incident on the mask 6 is diffused light.

The working process of the exposure apparatus according to the first embodiment of the present invention will be described in detail below with reference to FIGS. 6 and 7. FIG. 6 is a schematic diagram of exposure light according to Embodiment 1 of the present invention, and FIG. 7 is an enlarged schematic view showing a partial region during exposure according to Embodiment 1 of the present invention.

Specifically, in practical applications, in the process of fabricating a large-sized liquid crystal panel, a large-sized mask is required to form a desired pattern. The mask will be bent and deformed due to gravity. The center portion of the mask is drooped and the edge portion is lifted. As shown in Fig. 7, the arc of the curved mask 6 shown in a side view can be approximated as a straight line in a small range. The edge of the mask 6 is subjected to magnification analysis, in which a first pattern 11 of size L1 is formed on the lower surface 10 of the mask 6. The first pattern 11 is an opening, that is, a light transmitting region. The light emitted from the light source 1 passes through the first plane mirror 2, the fly-eye lens 3, and the concave mirror 4 to reach the second plane mirror 5, is reflected by the second plane mirror 5, and is incident on the mask sheet 6. The outermost edge ray 12' of the light irradiated to the mask 6 by the exposure light is incident on the upper surface 9 of the reticle 6 at a diffusion angle, and is refracted in the reticle 6 and incident on the lower surface 10 of the reticle 6, wherein The diffusion angle ^ is an angle between the exposure light and a direction perpendicular to the substrate 8. The light ray 12' passing through the first pattern 11 is irradiated onto the substrate 8, and the exposure process to the substrate 8 is completed. Thereafter, a second pattern 7' (exposure pattern) having a size of L ₃ is formed on the substrate 8 by a developing and etching process.

According to an embodiment of the present invention, in order to eliminate the influence of the bending deformation of the mask, the pattern size on the exposed substrate is made to coincide with the pattern size on the mask, and the exposure light incident on the mask can be adjusted to be diffused. The light corresponds to the degree of bending of the reticle.

As shown in Fig. 7, the exposure light projected to the edge of the mask 6 by the exposure system according to the present embodiment is light which is appropriately diffused. The tangent at the edge of the curved mask 6 forms an angle with the horizontal plane. According to the geometry, it can be easily obtained that when the exposure angle of the light irradiated to the edge of the mask 6 is 0 = ^, it can be realized.

2

u = , where the diffusion angle ø is the angle between the exposure light and the direction perpendicular to the substrate.

In the present embodiment, the diffusion angle of the light projected to the edge of the mask 6 can be adjusted to an appropriate size by changing the distance between the fly-eye lens 3 and the concave mirror 4. The distance between the fly-eye lens 3 and the concave mirror 4 can be set according to the following equation (1):

Wherein, the radius of the concave mirror 4, /^ is the radius of curvature of the concave mirror 4, which is ^. Therefore, when the value of the angle between the tangent to the horizontal plane at the edge of the mask 6 is measured and / / fixed, the exposure light at the edge of the mask 6 can be obtained according to the above formula. The diffusion angle ^ is a distance that is adapted to the curvature of the reticle. By setting the position of the fly-eye lens 3 at the appropriate distance, the diffusion angle 0 = ^ of the outermost edge ray 12' of the light of the exposure light to the mask 6 can be made. Result, the second graphic 7 '

2

The width L ₃ is equal to the width L of the first pattern 11, B 卩 LfL. Therefore, by the exposure apparatus of the embodiment, the adverse effect of the bending deformation of the large reticle caused by gravity during the production process on the size of the exposure pattern is eliminated. The display quality of the liquid crystal display device product is improved. In some embodiments, the divergence angle of the light rays incident at any point on the reticle 6 may preferably be appropriately adjusted. That is, according to the following equation, the diffusion angle of the light illuminating at any point on the mask 6 is adjusted to be equal to half the angle between the tangent at the corresponding point on the mask 6 in the curved state and the horizontal plane:

(2)

' 2

Therefore, instead of using the diffusion angle of the exposure light at the edge of the mask, the diffusion angle of the light at any point on the mask can be used to calculate ^ based on the above equations (1) and (2), thereby obtaining a mask. The curved condition is adapted to the divergent rays. In a preferred embodiment of the invention, the radius of the concave mirror 4 can be set equal to the radius of curvature _{A of the} concave mirror 4, ie

R, = p _x ( 3), and appropriately adjust the distance between the concave mirror 4 and the fly-eye lens 3 such that the above equation (1) holds: d, (1)

Substituting equation (3) into the above equation (1), the following equation (4) is obtained. Where 0 is the diffusion angle of the exposure light at the edge of the mask 6.

2

In some embodiments of the present invention, instead of merely changing the distance between the fly-eye lens 3 and the concave mirror 4, the radius of the concave mirror 4, the radius of curvature _{A of the} concave mirror 4, the fly-eye lens 3 and the concave surface may be simultaneously changed. The distance between the mirrors 4 is any one or more of the three parameters, as long as the relationship between the three satisfies the equation d,

In addition, in some other embodiments, the exposure light emitted by the light source system in the exposure device may be diffused by changing parameters such as size, position, shape, or other components of the light source system or by adding some components. And by appropriate adjustment to achieve the best match between the diffusion angle of the diffused light and the curvature of the mask.

In the prior art light source system, the distance between the fly-eye lens 3 and the concave mirror 4 is exactly half of the radius of curvature of the concave mirror 4. In order to distinguish from the embodiment of the present invention, the distance between the fly-eye lens 3 and the concave mirror 4 in the prior art light source system is D, and the radius of curvature of the concave mirror 4 is p, then the compound eye in the prior art light source system The distance D between the lens 3 and the concave mirror 4 is D = 2, that is, the fly-eye lens 3 is at the position of the focus of the concave mirror 4. The light emitted by the light source is converted into parallel light and incident on the mask 6 through the components in the light source system.

The present invention solves the problem of pattern size deviation formed on the substrate 8 caused by the bending deformation of the mask sheet 6, and converts the parallel light incident perpendicularly to the mask sheet 6 into diffused light so that the pattern formed on the substrate 8 and the pattern on the mask sheet 6 The dimensions are the same. The embodiment of the present invention can change the distance between the fly-eye lens 3 and the concave mirror 4 in the prior art light source system, so that the light emitted by the light source system has a certain diffusion angle. Specifically, the fly-eye lens 3 can be moved to the side of the concave mirror 4 by the following distance:

Making the distance between the concave mirror 4 and the fly-eye lens 3 satisfied

(—— + p ² +R^jR ² -p ² ) an0

d, =D

R

R- sa0 In addition, the embodiment of the present invention can also change the radius of the concave mirror 4 or the radius of curvature of the concave mirror 4 to make the light emitted by the light source system have a certain diffusion angle, or simultaneously change the radius of the concave mirror 4, the concave mirror 4 The radius of curvature _P1 , and any one or more of the distance between the concave mirror and the fly-eye lens, as long as the three satisfy d, =D, - (wherein, in the embodiment of the present invention)

The radius of the concave mirror 4, ^ is the radius of curvature of the concave mirror 4, A = †). Of course, the light emitted by the light source system in the exposure apparatus can be made to diffuse light by changing the size, position, or addition of other components in the light source system. In the exposure apparatus provided in this embodiment, since the light source system can provide the diffused light to the substrate to be exposed as the exposure light, the substrate exposure can be effectively solved due to the bending deformation of the mask during the manufacturing process of the large-sized liquid crystal display device substrate. The problem of pattern size deviation ensures the critical dimension accuracy of the substrate pattern, thereby improving the display quality of the liquid crystal display device.

FIG. 8 is a schematic flow chart of an exposure method according to Embodiment 2 of the present invention, and the exposure method is based on the above exposure apparatus.

Referring to Fig. 8, in step S101, the degree of curvature of the mask is measured.

In a specific embodiment, the curvature of the mask is measured to determine the angle between the tangent at the edge of the mask and the horizontal plane or to determine the angle between the tangent and the horizontal plane at several points on the mask, and calculate the tangent at any point on the mask. The angle between the horizontal plane or the angle between the tangent at any point and the horizontal plane.

In step S102, the diffusion of the exposure light is adjusted according to the measured curvature of the mask. Corner.

Specifically, the diffusion angle of the exposure light is adjusted according to the measured curvature of the mask to adjust the diffusion angle of the light irradiated to the edge of the mask by the exposure light to satisfy 0 = ^; or

2 Adjust the diffusion angle of the light at any point of the exposure light to the reticle, which satisfies θ. = .

' 2

The specific process for implementing the exposure method will be described with reference to FIG. To realize the exposure method, it is necessary to first measure the curvature of the mask 6. The method of measuring the curvature of the mask 6 is as follows. For example, by measuring the pattern size on the mask 6, when the exposure light is parallel to normal incident light, the mask 6 is passed through the mask 6. The degree of curvature of the mask 6 can be calculated by the size L ₂ of the exposure pattern formed on the substrate 8 by exposure.

In one embodiment, only the angle α between the edge of the mask 6 and the horizontal plane can be measured or calculated, and then the diffusion angle of the exposure light incident on the edge region of the mask can be adjusted so that it satisfies θ=α/2, thereby An exposure pattern conforming to the size of the pattern on the mask 6 can be formed on the substrate 8.

In another embodiment, the degree of curvature can be characterized by the angle between the tangent at any point on the mask 6 and the horizontal plane, derived from the geometric relationship, o^arcos O^/L a adjusting the angle of the exposure light incident on the mask The diffusion angle of the light incident to the entire periphery of the mask 6 is made to satisfy φ.

2

Subsequently, the mask can be exposed by techniques known in the art, such as by first coating a photoresist on the substrate 8, and then exposing the substrate 8 using the diffused light adjusted in accordance with an embodiment of the present invention.

As shown in Figure 7, the size of the pattern of the mask is! ^, the size of the exposed pattern on the substrate is L ₃ , and the exposure method of the embodiment of the present invention can make the size of the pattern of the mask equal to the size L _{3 of the} exposed pattern on the substrate, that is, LfL

The exposure method provided in this embodiment is based on the above exposure apparatus, the exposure method includes: measuring a curvature of the mask; and bending according to the measured mask Adjusting the diffusion angle of the exposure light, which can effectively solve the problem of the dimensional deviation of the exposure pattern on the substrate caused by the bending deformation of the mask during the manufacturing process of the large-size liquid crystal display device substrate, thereby ensuring the accuracy of the critical dimension of the substrate pattern, thereby improving The display quality of the liquid crystal display device.

FIG. 9 is a schematic structural diagram of an exposure system according to Embodiment 3 of the present invention. As shown in FIG. 9, the exposure system includes: a mask 6 and an exposure device, and the exposure device adopts an exposure device according to any embodiment of the present invention. .

In the exposure system, the exposure device adjusts light emitted from a light source to become diffused light before being irradiated onto the mask 6. The diffused exposure light is irradiated onto the substrate via the mask, and the pattern of the mask is photolithographically patterned onto the substrate. The diffusion angle of the diffused light is appropriately adjusted to match the degree of bending of the mask 6. The exposure method according to the present invention as described above can be employed to adjust the diffusion angle of the diffused light.

The exposure system according to the present invention can effectively solve the problem of the dimensional deviation of the exposure pattern on the substrate caused by the bending deformation of the mask during the fabrication process of the large-size liquid crystal display device substrate, thereby ensuring the critical dimension accuracy of the substrate pattern, thereby improving the accuracy. The display quality of the liquid crystal display device. It is to be understood that the above embodiments are merely exemplary embodiments employed to explain the principles of the invention, but the invention is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of the invention, and such modifications and improvements are also considered to be within the scope of the invention.

Claims

Rights request

An exposure apparatus comprising:

a light source system for providing exposure light to a substrate to be exposed,

The exposure device is characterized in that the exposure light is diffused light, and the diffused light is irradiated onto the substrate to be exposed via a mask to etch the pattern of the mask onto the substrate to be exposed.

2. The exposure apparatus according to claim 1, wherein

The diffusion angle of the light irradiated to the edge of the mask by the exposure light depends on the degree of curvature of the mask in a bent state.

3. The exposure apparatus according to claim 2, wherein

If the angle between the tangent at the edge of the mask and the horizontal plane is ", the diffusion angle of the light irradiated to the edge of the mask by the exposure light is satisfied: Θ

2

4. The exposure apparatus according to claim 2, wherein

If the angle between the tangent of the mask at any point and the horizontal plane is, the diffusion angle of the light irradiated by the exposure light to any point of the mask satisfies:

The exposure apparatus according to any one of claims 1 to 4, wherein the light source system comprises a light source, a first plane mirror, a fly-eye lens, a concave mirror and a second plane mirror, and the light emitted by the light source is sequentially After passing through the first plane mirror, the fly-eye lens, the concave mirror, and the second plane mirror, the light illuminating the mask plate is diffused light.

The exposure apparatus according to claim 5, wherein the radius of the concave mirror is such that the radius of curvature of the concave mirror is A, and the distance between the concave mirror and the fly-eye lens is The relationship between the three parameters, ^ and satisfies: d, , where A is.

7. The exposure apparatus according to claim 6, wherein a radius of the concave mirror is equal to a radius of curvature A of the concave mirror.

8. The exposure apparatus according to claim 1, wherein the exposure apparatus comprises:

a machine for carrying the substrate to be exposed;

A mask holder for carrying the mask.

An exposure system comprising a mask and an exposure apparatus, characterized in that the exposure apparatus employs the exposure apparatus according to any one of claims 1-8.

10. An exposure method characterized by comprising the steps of:

Determining the curvature of the mask;

Adjusting a diffusion angle of the exposure light according to the measured curvature of the mask; and exposing the exposure light after the diffusion angle is adjusted to the substrate to be exposed via the mask to lithographically pattern the mask to the to be exposed On the substrate.

11. The exposure method according to claim 10, wherein the step of determining the curvature of the mask comprises determining an angle between a tangent at a edge of the mask and a horizontal plane;

The step of adjusting the diffusion angle of the exposure light according to the measured curvature of the mask includes adjusting the diffusion angle 0 of the light irradiated by the exposure light to the edge of the mask to satisfy.

2

12. The exposure method according to claim 10, wherein the step of determining the curvature of the mask comprises determining a number of points of the mask And the horizontal angle between the tangent line to calculate the reticle office at a point tangent angle with the horizontal a _t, or direct measurement of the reticle to any angle with the horizontal tangent line at a point;

The step of adjusting a diffusion angle of the exposure light according to the measured curvature of the mask includes adjusting a diffusion angle of the light irradiated to the mask at any point of the mask to satisfy

The exposure method according to claim 11, wherein the radius of the concave mirror is such that the radius of curvature of the concave mirror is ^, and the distance between the concave mirror and the fly-eye lens is adjusted by the following equation One or more of the parameters, A and any of them are used to adjust the diffusion angle d, where A is .

14. The exposure method according to claim 13, wherein the radius is equal to a radius of curvature ^ of the concave mirror.