CN106502044B

CN106502044B - Mask plate and manufacturing method thereof

Info

Publication number: CN106502044B
Application number: CN201710017420.4A
Authority: CN
Inventors: 吴康成
Original assignee: Kunshan Guoxian Photoelectric Co Ltd
Current assignee: Kunshan Guoxian Photoelectric Co Ltd
Priority date: 2017-01-10
Filing date: 2017-01-10
Publication date: 2020-01-24
Anticipated expiration: 2037-01-10
Also published as: CN106502044A

Abstract

The invention relates to a mask plate and a manufacturing method thereof, wherein the manufacturing method of the mask plate comprises the following steps: providing a substrate; processing one surface of the substrate into a concave surface; and manufacturing a mask pattern on the concave surface. According to the mask plate and the manufacturing method thereof, the mask surface of the mask plate is processed into the concave surface, so that the mask surface of the mask plate is close to a plane when the mask plate is bent due to self weight, the consistency of exposure intervals is ensured, and the uniformity of the size of an exposed graph is further ensured.

Description

Mask plate and manufacturing method thereof

Technical Field

The invention relates to the field of flat panel display manufacturing, in particular to a mask plate and a manufacturing method thereof.

Background

In the manufacturing of flat panel display devices, a photolithography process is one of the most important process steps. The photolithography process is a process of transferring a pattern on a mask plate onto a glass substrate or a flexible substrate. A mask (also referred to as a reticle) is a transparent substrate having transparency to exposure light, and has at least one pattern (i.e., mask pattern) thereon having light-shielding property against exposure light.

In the actual production process, the mask plate is bent due to the self weight, so that the uniformity of the size of the exposed pattern is poor. Please refer to fig. 1, which is a schematic structural diagram of an exposure process using a mask in the prior art. As shown in fig. 1, a conventional mask 100 includes a mask face 10a and a non-mask face 10b opposite to the mask face 10a, the mask face 10a and the non-mask face 10b are both flat faces, a mask pattern 12 is provided on the mask face 10a, the mask face 10a of the mask 100 is mounted on an exposure apparatus, and an exposure distance between the mask 100 and a substrate 101 is inconsistent due to bending caused by its own weight, for example, an exposure distance G2 between a central region of the mask 100 and the substrate 101 is smaller than an exposure distance G1 between an edge region of the mask 100 and the substrate 101.

In general, the exposed pattern size (CD) increases with increasing exposure pitch. Under the same exposure amount, if the exposure pitch of the central region is small and the exposure pitch of the edge region is large, the size of the pattern exposed in the central region is small, and the size of the pattern exposed in the edge region is large, i.e. the sizes of the exposed patterns are not uniform (e.g. CD2 < CD 1). That is, the uniformity of the pattern size exposed by using the conventional mask 100 is poor.

Therefore, how to solve the problem that the uniformity of the dimension of the exposed pattern is poor due to the inconsistent exposure space caused by the bending of the existing mask plate becomes a technical problem to be solved by the technicians in the field.

Disclosure of Invention

The invention aims to provide a mask plate and a manufacturing method thereof, and aims to solve the problem that the uniformity of the size of an exposed graph is poor due to inconsistent exposure space caused by bending of the traditional mask plate.

In order to solve the above problems, the present invention provides a method for manufacturing a mask, including:

providing a substrate;

processing one surface of the substrate into a concave surface; and

and manufacturing a mask pattern on the concave surface.

Optionally, in the method for manufacturing a mask, the step of processing one surface of the substrate into a concave surface includes:

measuring the physical dimension and weight of the substrate;

carrying out deformation simulation on the mask plate according to the overall dimension and the weight of the substrate; and

and processing one surface of the substrate according to the deformation simulation result to form a concave surface.

Optionally, in the manufacturing method of the mask plate, the substrate is a transparent substrate.

Optionally, in the manufacturing method of the mask plate, the transparent substrate is made of quartz.

Optionally, in the manufacturing method of the mask plate, the mask pattern is made of a light-shielding material.

Correspondingly, the invention also provides a mask plate manufactured by the manufacturing method of the mask plate, and the mask plate comprises the following components: the mask comprises a substrate and a mask pattern formed on the substrate, wherein one surface of the substrate with the mask pattern is a mask face, and the mask face is a concave face.

Optionally, in the mask plate, the concave surface is processed according to a deformation simulation result of the mask plate.

Optionally, in the mask, the substrate is a transparent substrate.

Optionally, in the mask, the transparent substrate is made of quartz.

Optionally, in the mask, the method further includes: the non-mask surface is a plane and is opposite to the mask surface.

According to the mask plate and the manufacturing method thereof, the mask surface of the mask plate is processed into the concave surface, so that the mask surface of the mask plate is close to a plane when the mask plate is bent due to self weight, the consistency of exposure intervals is ensured, and the uniformity of the size of an exposed graph is further ensured.

Drawings

FIG. 1 is a schematic diagram of a structure for exposure using a mask according to the prior art;

fig. 2 is a flowchart of a mask manufacturing method according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram corresponding to step one in the mask manufacturing method according to the embodiment of the present invention;

fig. 4 is a schematic structural diagram corresponding to step two in the mask manufacturing method according to the embodiment of the present invention;

FIG. 5 is a diagram illustrating a deformation curve simulation of a mask according to an embodiment of the present invention;

fig. 6 is a diagram of deformation amount distribution simulation of a mask according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram corresponding to step three in the mask manufacturing method according to the embodiment of the present invention;

fig. 8 is a schematic structural diagram of exposure by using the mask according to the embodiment of the present invention.

Detailed Description

The mask and the method for manufacturing the mask according to the present invention will be described in detail with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

Please refer to fig. 2, which is a flowchart illustrating a mask fabricating method according to an embodiment of the invention. As shown in fig. 2, the mask manufacturing method includes the steps of:

the method comprises the following steps: providing a substrate;

step two: processing one side of the substrate into a concave surface;

step three: and manufacturing a mask pattern on the concave surface.

The mask manufacturing method according to the embodiment of the present invention is described in more detail below with reference to fig. 3 to 7.

First, as shown in fig. 3, a substrate 20 is provided. The substrate 20 is, for example, a transparent substrate made of, for example, quartz. In practical applications, other materials may be used to form the substrate 20 as required. The substrate 20 has a rectangular parallelepiped structure, and a cross section thereof is rectangular or square.

Next, as shown in fig. 4, one side of the substrate 20 is processed to be a concave surface (i.e., a curved surface gradually depressed from the periphery to the center). The specific process of processing one side of the substrate into a concave surface comprises the following steps: first, the physical dimensions and weight of the substrate 20 are measured; then, according to the overall dimension and weight of the substrate 20, deformation simulation is carried out on the mask plate; then, one surface of the substrate 20 is processed according to the deformation simulation result to form a concave surface.

In this embodiment, the deformation simulation result is obtained by using finite element analysis software (ANSYS), which can calculate the deformation amount and simulate the deformation curve (fig. 5) and the deformation amount distribution (fig. 6) when the mask is bent by its own weight, according to the external dimensions (including length, width, and thickness), weight, and elastic modulus of the substrate 20. As shown in fig. 5 and 6, the deformation amount of the mask is related to the position thereof, the deformation amount at the edge position is the smallest, and the deformation amount h at the center point position is the largest.

In this embodiment, the thickness of the substrate 20 is on the order of millimeters, and the depth of the concave recess is on the order of micrometers.

In this embodiment, the shape of the concave surface is processed according to the deformation simulation result. After the processing is finished, the shape of the concave surface is consistent with the deformation simulation curve. For example, if the amount of deformation h at the center point position is 5 μm, the depression depth h' of the concave surface is also 5 μm. When the concave surface is placed downward, the substrate 20 is deformed by its own weight so that the concave surface tends to be a flat surface. In other embodiments, the shape of the concave surface may be processed in a certain proportion with reference to the deformation simulation curve, as long as the concave surface can also approach a plane when placed downward.

Then, as shown in fig. 7, a mask pattern 22 is formed on the concave surface using a light-shielding material, and the mask pattern 22 has light-shielding properties against exposure light.

And finishing the manufacturing of the mask plate 200, wherein one side of the mask plate 200 with the mask patterns 22 is a mask surface 20a, the side opposite to the mask surface 20a is a non-mask surface 20b, the mask surface 20a is a concave surface, and the specific shape of the concave surface depends on the deformation of the mask plate.

In the mask manufacturing method provided in this embodiment, the amount of deformation of the mask is compensated in advance by making one side of the substrate concave. When the mask plate 200 is deformed due to the gravity, the mask surface 20a of the mask plate 200 tends to a plane, and thus the exposure distance of the mask plate 200 is kept consistent.

Correspondingly, this embodiment still provides a mask plate. Referring to fig. 7, the mask 200 includes: the mask structure comprises a substrate 20 and a mask pattern 22 formed on the substrate 20, wherein one side of the substrate 20 with the mask pattern 22 is a mask surface 20a, the mask surface 20a is a concave surface, and the specific shape of the concave surface depends on the deformation amount of a mask plate.

Specifically, the mask plate 200 includes a mask surface and a non-mask surface opposite to the mask surface, a mask pattern is formed on the mask surface, and the mask surface is a curved surface (i.e., a concave surface) which is recessed inwards from the periphery to the center, and the more towards the center, the thinner the mask plate 200 is, the more towards the periphery, the thicker the mask plate 200 is.

Referring to fig. 8, which is a schematic structural view of exposure by using a mask plate according to an embodiment of the present invention, as shown in fig. 8, the mask plate 200 is installed in a lithographic apparatus, a mask surface 20a of the mask plate faces downward toward a substrate 201, and when the mask plate deforms downward due to gravity, a non-mask surface 20b of the mask plate 200 changes from a plane to a curved surface, and the mask surface 20a of the mask plate 200 tends to be a plane.

When the mask plate 200 is used for exposure, because the mask plate 200 compensates the deformation in advance, the whole mask face 20a tends to a plane, and the exposure distance between the mask plate 200 and the substrate 201 is kept consistent, the uniformity of the size of the exposed pattern can be ensured.

In summary, in the mask plate and the manufacturing method thereof provided by the invention, the mask surface of the mask plate is processed into the concave surface, so that the mask surface of the mask plate is close to a plane when the mask plate is bent due to self weight, thereby ensuring the consistency of the exposure space and further ensuring the uniformity of the size of the exposed pattern.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims

1. A manufacturing method of a mask plate is characterized by comprising the following steps:

providing a substrate;

processing one surface of the substrate into a concave surface, wherein the shape of the concave surface is processed according to a deformation simulation result; and

making a mask pattern on the concave surface, wherein the process of processing one surface of the substrate into the concave surface comprises the following steps:

measuring the physical dimension and weight of the substrate;

2. A method for manufacturing a mask according to claim 1, wherein the substrate is a transparent substrate.

3. A method for manufacturing a mask according to claim 2, wherein the transparent substrate is made of quartz.

4. A method for manufacturing a mask according to claim 1, wherein the mask pattern is made of a light-shielding material.

5. A mask manufactured by the manufacturing method of the mask as claimed in any one of claims 1 to 4, comprising: the mask comprises a substrate and a mask pattern formed on the substrate, wherein one surface of the substrate with the mask pattern is a mask face, and the mask face is a concave face.

6. A mask plate according to claim 5, wherein the concave surface is processed according to a deformation simulation result of the mask plate.

7. A mask according to claim 5, wherein the substrate is a transparent substrate.

8. A mask according to claim 7, wherein the transparent substrate is made of quartz.

9. A mask according to claim 5, further comprising: the non-mask surface is a plane and is opposite to the mask surface.