阅读说明：本技术 薄膜晶体管基板和薄膜晶体管基板的制造方法 (Thin film transistor substrate and method for manufacturing thin film transistor substrate ) 是由 梶山康一 水村通伸 于 2018-07-03 设计创作，主要内容包括：能够提高TFT对折弯、卷绕等外力的耐久性并防止基板的破裂、缺损。在挠性基板(20),在与设置有薄膜晶体管的第一表面相反的一侧的第二表面形成有凹部(23),从与第一表面大致正交的第一方向观察,凹部(23)配置于不与薄膜晶体管重叠的位置。(The durability of the TFT against external forces such as bending and winding can be improved, and cracking and chipping of the substrate can be prevented. A recess (23) is formed in a second surface of the flexible substrate (20) on the side opposite to the first surface on which the thin film transistor is provided, and the recess (23) is disposed at a position not overlapping the thin film transistor when viewed from a first direction substantially orthogonal to the first surface.)

1. A thin film transistor substrate is characterized in that,

the disclosed device is provided with:

a flexible substrate; and

a thin film transistor disposed on the first surface of the flexible substrate,

a recess is formed in a second surface of the flexible substrate on a side opposite to the first surface,

the recess is disposed at a position not overlapping the thin film transistor when viewed from a first direction substantially orthogonal to the first surface.

2. The thin film transistor substrate according to claim 1,

the thin film transistors are arranged in plurality substantially along a second direction along the first surface,

the recess is formed in a band shape substantially along the second direction.

3. The thin film transistor substrate according to claim 2,

the concave portion has a substantially rectangular shape in which the first surface side is shorter than the second surface side when cut along a surface that is substantially orthogonal to the first direction and the second direction.

4. The thin film transistor substrate according to any one of claims 1 to 3,

the thickness of the portion of the flexible substrate that overlaps with the thin film transistor is twice or more the thickness of the portion of the flexible substrate where the recess is formed, when viewed from the first direction.

5. The thin film transistor substrate according to any one of claims 1 to 4,

the flexible substrate is formed with a circular arc shape at a boundary portion between the second surface and the concave portion and at an end portion of a bottom surface of the concave portion.

6. A method for manufacturing a thin film transistor substrate,

the method comprises the following steps:

a first step of forming a concave portion and a convex portion on a first surface of a support substrate;

a second step of forming a flexible substrate by applying a resin to the first surface so as to cover the concave portion and the convex portion;

a third step of forming a thin film transistor on a second surface of the flexible substrate, which is a surface opposite to the surface on which the support substrate is provided, in a region where the convex portion is not formed in the first step; and

a fourth step of peeling the flexible substrate from the support substrate.

7. The method of manufacturing a thin film transistor substrate according to claim 6,

in the first step, the convex portion is formed in a band shape,

in the third step, a plurality of the thin film transistors are formed substantially along the longitudinal direction of the projection.

8. The method of manufacturing a thin film transistor substrate according to claim 6 or 7,

in the first step, a corner portion of the concave portion and the convex portion is formed in a circular arc shape.

9. The method for manufacturing a thin film transistor substrate according to any one of claims 6 to 8,

in the first step, an alignment mark is formed on the first surface,

in the third step, the thin film transistor is formed based on the alignment mark.

10. The method for manufacturing a thin film transistor substrate according to any one of claims 6 to 8,

in the second step, an alignment mark is formed on the second surface,

in the third step, the thin film transistor is formed based on the alignment mark.

Technical Field

The present invention relates to a thin film transistor substrate and a method of manufacturing the thin film transistor substrate.

Background

Patent document 1 discloses a thin film transistor array substrate for driving a flexible display, in which an island-shaped buffer layer for relaxing stress is formed on a plastic substrate, and a TFT is formed on the buffer layer, thereby securing high bending resistance regardless of the semiconductor material.

Disclosure of Invention

Problems to be solved by the invention

In the invention described in patent document 1, since the plastic substrate and the buffer layer are made of different materials, internal stress may occur in the thin film transistor array substrate due to a temperature change or the like. In addition, since the buffer layer is provided on the plastic substrate, it is easy to apply a force to the boundary portion between the plastic substrate and the buffer layer when the thin film transistor array substrate is bent. As a result, the buffer layer may be peeled off from the plastic substrate, and cracks or defects may occur in the thin film transistor array substrate.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a thin film transistor substrate and a method for manufacturing the thin film transistor substrate, which can improve durability of a Thin Film Transistor (TFT) against external forces such as bending and winding, and can prevent cracking and chipping of the substrate.

Means for solving the problems

In order to solve the above problem, a thin film transistor substrate according to the present invention includes, for example: a flexible substrate; and a thin film transistor provided on a first surface of the flexible substrate, wherein a recess is formed in a second surface of the flexible substrate opposite to the first surface, and the recess is disposed at a position not overlapping the thin film transistor when viewed from a first direction substantially orthogonal to the first surface.

In the thin film transistor substrate of the present invention, the concave portion is formed at a position of the flexible substrate not overlapping with the thin film transistor. Therefore, the thickness of the flexible substrate at a position not overlapping with the TFT is thinner than the thickness of the flexible substrate at a position overlapping with the TFT. Therefore, the thin portion of the flexible substrate is bent first, and deformation of the flexible substrate at a position overlapping with the TFT is suppressed. This can improve the durability of the TFT against external forces such as bending and winding. Further, since a part of the flexible substrate is easily deformed by forming the concave portion, it is possible to prevent the substrate from being broken or chipped due to a difference in internal stress or thermal expansion coefficient.

Here, the plurality of thin film transistors may be provided substantially along a second direction along the first surface, and the recess may be formed substantially along the second direction in a stripe shape. This facilitates the winding of the thin film transistor substrate in a direction substantially orthogonal to the extending direction of the recess. In addition, the thin film transistor substrate 1 is less likely to bend in the extending direction of the concave portion, and can suppress the application of force to the TFT.

Here, the concave portion may have a substantially rectangular shape in which the first surface side is shorter than the second surface side when cut along a plane that is substantially orthogonal to the second direction and the first direction. Thus, when the thin film transistor substrate is deformed, the opposing wall surfaces of the recess portions are less likely to come into contact with each other, and generation of dust can be suppressed.

Here, when viewed from the first direction, a thickness of a portion of the flexible substrate which overlaps with the thin film transistor may be two times or more a thickness of a portion of the flexible substrate where the recess is formed. This makes it easy to deform the portion where the recess is formed, and suppresses the TFT from being biased.

Here, the flexible substrate may be formed with a circular arc shape at a boundary portion between the second surface and the concave portion and a bottom surface end portion of the concave portion. Therefore, when the thin film transistor substrate is wound, the edge of the thin film transistor substrate is not scraped, and the generation of dust can be prevented.

In order to solve the above problem, a method for manufacturing a thin film transistor substrate according to the present invention includes, for example: a first step of forming a concave portion and a convex portion on a first surface of a support substrate; a second step of forming a flexible substrate by applying a resin to the first surface so as to cover the concave portion and the convex portion; a third step of forming a thin film transistor on a second surface of the flexible substrate, which is a surface opposite to the surface on which the support substrate is provided, in a region where the convex portion is not formed in the first step; and a fourth step of peeling the flexible substrate from the support substrate.

In the method for manufacturing a thin film transistor substrate according to the present invention, the concave portion and the convex portion are formed on the first surface of the support substrate, and the resin is applied to the first surface so as to cover the concave portion and the convex portion, thereby forming the flexible substrate. Thus, the recess can be formed in the flexible substrate without additional processing. Further, it is easy to make the shape of the recess of the flexible substrate a substantially rectangular shape having a first surface side shorter than a second surface side.

In the first step, the protruding portion may be formed in a band shape, and in the third step, the plurality of thin film transistors may be formed substantially along a longitudinal direction of the protruding portion. This makes it possible to form the recessed portion of the flexible substrate in a band shape and form the TFT at a position of the flexible substrate not overlapping the recessed portion.

In the first step, a corner portion of the concave portion and the convex portion may be formed in a circular arc shape. Thus, the concave portion of the flexible substrate can be formed into an arc shape without additional processing.

Here, in the first step, an alignment mark may be formed on the first surface, and in the third step, the thin film transistor may be formed based on the alignment mark. Thus, when forming the TFT, the positions of the convex portions and the concave portions, that is, the positions where the TFT is to be formed can be grasped.

Here, in the second step, an alignment mark may be formed on the second surface, and in the third step, the thin film transistor may be formed based on the alignment mark. Thus, when forming the TFT, the positions of the convex portions and the concave portions, that is, the positions where the TFT is to be formed can be grasped.

Effects of the invention

According to the present invention, the durability of the TFT against external forces such as bending and winding can be improved, and cracking and chipping of the substrate can be prevented.

Drawings

Fig. 1 is a schematic perspective view showing a thin film transistor substrate 1 according to a first embodiment.

Fig. 2 (a) is a diagram illustrating the arrangement of the sub-pixels 10 in the thin film transistor substrate 1, and fig. 2 (B) is a partially enlarged view of fig. 2 (a).

Fig. 3 is a cross-sectional view schematically showing the thin film transistor substrate 1.

Fig. 4 is a diagram schematically showing how the thin film transistor substrate 1 is bent.

Fig. 5 is a diagram illustrating the arrangement of the thin-film portion 24 in the thin-film transistor substrate 1, fig. 5 (a) is a schematic side view showing the flexible substrate 20, and fig. 5 (B) is a schematic front view showing the flexible substrate 20.

Fig. 6 is a flowchart illustrating a flow of the method for manufacturing the thin film transistor substrate 1.

Fig. 7 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Fig. 8 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Fig. 9 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Fig. 10 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Fig. 11 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Fig. 12 is a view schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The thin film transistor substrate of the present invention is a substrate for a flexible display that can be wound and bent, and is a substrate for driving the flexible display. Liquid crystal and organic EL can be used for a flexible display, and a flexible display using organic EL will be described below as an example.

Fig. 1 is a schematic perspective view showing a thin film transistor substrate 1 according to a first embodiment. The thin film transistor substrate 1 is sheet-shaped, and a plurality of sub-pixels 10 are formed on the thin film transistor substrate 1. The sub-pixels 10 are provided in plurality substantially along the surface direction (x direction and y direction) of the thin film transistor substrate 1. The position and arrangement of the sub-pixels 10 shown in fig. 1 are not limited to the above example.

A pixel of a flexible display (not shown) is composed of 3 sub-pixels 10. The 3 sub-pixels have organic EL element layers (not shown) emitting red, blue, and green light, respectively.

Fig. 2 (a) is a diagram illustrating the arrangement of the sub-pixels 10 in the thin film transistor substrate 1, and fig. 2 (B) is a partially enlarged view of fig. 2 (a).

The sub-pixels 10 are arranged in a substantially grid-like manner in the x-direction and the y-direction. The sub-pixel 10 mainly has a pixel electrode 11, Thin Film Transistors (TFTs) 12 and 13, and a holding capacitor 14. Further, wirings 15, 16, and 17 are formed inside the sub-pixel 10 and between adjacent sub-pixels 10. The structure and arrangement of the sub-pixel 10 shown in fig. 2 are not limited to the above example.

Fig. 3 is a cross-sectional view schematically showing the thin film transistor substrate 1. The thin film transistor substrate 1 includes a flexible substrate (flexible substrate) 20. The flexible substrate 20 is formed of, for example, a resin that is cured by energy supply, for example, a photocurable resin, a thermosetting resin, or the like. In the present embodiment, a polyimide resin is used for the flexible substrate 20.

TFTs 12 and 13 electrically connected to unillustrated wirings are provided on the front surface 21 of the flexible substrate 20. In fig. 3, only the TFT12 among the TFTs 12 and 13 included in the sub-pixel 10 is shown, and the TFT13 is not shown.

A plurality of recesses 23 are formed in the rear surface 22 of the flexible substrate 20. The concave portion 23 has a substantially rectangular shape in which the front surface 21 side is shorter than the rear surface 22 side when cut along the surfaces in the x direction and the z direction (the directions substantially orthogonal to the x direction and the y direction). Arc shapes 23a and 23b are formed at the boundary between the rear surface 22 and the recess 23 and at the bottom end of the recess 23.

By forming the concave portion 23 in the flexible substrate 20, the thin portion 24 thinner than the thick portion 25 is formed. The thickness t2 of the thick portion 25 is twice or more the thickness t1 of the thin portion 24. The recess 23 is disposed at a position not overlapping the TFT12 when viewed in the z direction.

Fig. 4 is a diagram schematically showing how the thin film transistor substrate 1 is bent. When the thin film transistor substrate 1 is bent, the thin portion 24 is bent first, and the bending of the thick portion 25 is suppressed. When the thin film transistor substrate 1 is bent, the thin portion 24 is largely deformed, and the deformation of the thick portion 25 is suppressed. As a result, it is possible to suppress the TFT12 provided above the thick portion 25 from being biased.

Further, since the arc shape 23b is formed, it is possible to prevent the force from concentrating on the corner portion of the concave portion 23 and causing a crack or the like in the flexible substrate 20 when the thin film transistor substrate 1 is bent. Further, since the arc shape 23a is formed, it is possible to prevent the surface (not shown) of the flexible display from being scraped by the edge and generating dust when the thin film transistor substrate 1 is wound.

Note that, although fig. 4 shows a case where the thin film transistor substrate 1 is bent in a direction in which the interval between the adjacent TFTs 12 is increased, the thin film transistor substrate 1 may be bent in a direction in which the interval between the adjacent TFTs 12 is decreased.

Fig. 5 is a diagram illustrating the arrangement of the concave portion 23 in the thin film transistor substrate 1, fig. 5 (a) is a schematic side view showing the flexible substrate 20, and fig. 5 (B) is a schematic front view showing the flexible substrate 20. In fig. 5 (B), the positions where the sub-pixels 10 are formed are shown by two-dot chain lines. In fig. 5 (B), the position of the concave portion 23 is hatched.

The TFTs 12, 13 are arranged substantially along the y-direction. The concave portion 23 is formed in a band shape substantially in the y direction at a position not overlapping with the TFTs 12, 13. As a result, the flexible substrate 20 (i.e., the thin film transistor substrate 1) can be wound in the x direction (see arrow in fig. 4), which is a direction substantially perpendicular to the extending direction of the concave portion 23. Further, since the recess 23, that is, the thick portion 25 is formed in a substantially strip shape in the y direction, the thin film transistor substrate 1 is less likely to bend in the y direction, and the force applied to the TFTs 12, 13 can be suppressed.

Next, a method for manufacturing the thin film transistor substrate 1 of the present embodiment will be described. Fig. 6 is a flowchart illustrating a flow of the method for manufacturing the thin film transistor substrate 1. Fig. 7 to 12 are diagrams schematically showing the appearance of the thin film transistor substrate 1 in the manufacturing process. Fig. 7, 9 to 12 are cross-sectional views along the xz plane, and are partially enlarged views. Fig. 8 is a plan view.

< carrier glass preparation step: step S1>

When the thin film transistor substrate 1 is manufactured, a support substrate is prepared. In the present embodiment, the carrier glass 50 is used as a support substrate.

As shown in fig. 7, a convex portion 51 and a concave portion 52 are formed on the upper surface of the carrier glass 50. As a method for forming the convex portions 51 and the concave portions 52, a method for forming the convex portions 51 by printing on the carrier glass 50, a method for forming the concave portions 52 by etching or the like by removing the upper surface of the carrier glass 50, and the like are conceivable. Printing is performed by applying resin to the carrier glass 50.

In the present embodiment, the convex portions 51 are printed on the upper surface of the carrier glass 50, thereby forming the concave-convex portions on the upper surface of the carrier glass 50. The portion of the upper surface of the carrier glass 50 not printed becomes the recess 52. The convex portion 51 is formed in a circular arc shape 51a, 51b at the corner.

As shown in fig. 8, the convex portion 51 is formed substantially in a band shape in the y direction. When the convex portions 51 are printed on the carrier glass 50, the alignment marks 53 are printed on the upper surface of the carrier glass 50. In the present embodiment, the alignment mark 53 has a substantially cross shape, but the shape of the alignment mark 53 is not limited to this. In addition, the position of the alignment mark 53 is not limited thereto.

< flexible substrate Forming Process: step S2>

As shown in fig. 9, the flexible substrate 20 is formed by applying a resin to be the flexible substrate 20 on the upper surface (+ z-side surface) of the carrier glass 50 so as to cover the convex portions 51 and the concave portions 52. In the present embodiment, first, a resin to be the adhesive layer 55 is applied to the upper surface of the carrier glass 50, and then a resin (here, a polyimide resin) to be the flexible substrate 20 is applied thereto.

The adhesive layer 55 is used to facilitate the peeling of the flexible substrate 20 from the carrier glass 50 after the production, and various resin materials can be used. The adhesive layer 55 is not essential.

A resin in a solution state is used as the resin to be the adhesive layer 55 and the polyimide resin. The step of applying the resin in a solution state on the carrier glass 50 can be performed by a coating method such as a spin coating method or a printing method such as screen printing. After the coating, the adhesive layer 55 and the flexible substrate 20 are cured. The method of curing varies depending on the resin (photocuring, thermosetting, etc.), but since the polyimide resin is a photocurable resin, the polyimide resin is cured by irradiation with light in the present embodiment. Thereby, the flexible substrate 20 is formed on the carrier glass 50.

Since the convex portions 51 and the concave portions 52 are formed on the upper surface of the carrier glass 50, the surface (the surface on the opposite side from the carrier glass 50) is flat, and the polyimide resin is applied and cured, thereby forming the unevenness on the back surface of the flexible substrate 20. The convex portion 51 is formed as a concave portion 23, and the portion coated on the upper side of the convex portion 51 is formed as a thin portion 24. The portion applied to the upper side of the recess 52 is a thick portion 25.

Further, since the arc shapes 51a and 51b are formed at the corners of the convex portion 51, the arc shapes 23a and 23b are formed in the concave portion 23.

< TFT formation Process: step S3>

TFTs 12, 13 are formed on the upper side of the flexible substrate 20. Further, an underlayer may be formed on the upper side of the flexible substrate 20, and the TFT may be formed on the underlayer. The TFT forming process (step S3) may use a known technique, and thus the details of each process are omitted.

First, the gate electrode 61 is formed on the upper side of the flexible substrate 20, and the gate insulating layer 62 is formed thereon (see steps S31, S32, fig. 10 of fig. 6). In this case, a part of the wiring (power supply line, selection line) may be formed.

Thereafter, an a-Si layer is formed over the gate insulating layer 62, a dehydrogenation process is performed by irradiating laser light to the a-Si layer, and the amorphous silicon is crystallized (laser annealing process), thereby obtaining a polycrystalline silicon (p-Si) layer 63 (see step S33, fig. 10 of fig. 6). The source electrode 64 and the drain electrode 65 are formed thereon (see step S34 in fig. 6 and fig. 11). At this time, a part of the wiring (data line) may be formed.

Next, the TFT protection layer 66 is formed (see step S35 in fig. 6 and fig. 12), and the ITO film (transparent electrode film) 67 is formed on the protection layer 66 (see step S36 in fig. 6 and fig. 12). The TFT protecting layer 66 can use an organic resin. A recess 66a is formed in the TFT protection layer 66, and the ITO film 67 is in contact with the drain electrode 65. After that, the acrylic resin 68 is injected into the space formed by the concave portion 66a (see step S37 of fig. 6, fig. 12).

Thereby, the TFT forming process (step S3) ends. In the TFT forming step (step S3), a plurality of TFTs are formed substantially along the longitudinal direction (y direction) of the convex portions 51 in the region where the convex portions 51 are not formed in the carrier glass preparing step (step S1).

In the TFT forming process (step S3), TFTs are formed based on the alignment marks 53 formed in the carrier glass preparing process (step S1). Since the position of the convex portion 51 with respect to the position of the alignment mark 53 is known in advance, it becomes clear at which position the TFT is formed by referring to the alignment mark 53 even if the position of the convex portion 51 is not visible.

Through the above steps, the thin film transistor substrate 1 is formed. After the thin film transistor substrate 1 is formed, the organic EL is formed and sealed, and then the flexible substrate 20 is peeled off from the carrier glass 50.

In the present embodiment, the alignment mark 53 is formed in the carrier glass preparation step (step S1), but instead of forming the alignment mark 53 in the carrier glass preparation step (step S1), the alignment mark may be formed on the surface on the opposite side of the flexible substrate 20 from the surface on which the carrier glass 50 is provided (+ z-side surface) after the flexible substrate 20 is formed in the flexible substrate forming step (step S2). In this case, since the alignment mark is easily confirmed in the TFT forming process (step S3), there is an advantage that the TFT is easily formed from the alignment mark.

In this embodiment, since the TFTs 12 and 13 are formed on the flexible substrate 20 and the recess 23, that is, the thin portion 24 is formed at a position not overlapping with the TFTs 12 and 13 when viewed from the z direction, the durability of the TFTs against external forces such as bending and winding of the substrate can be improved.

In addition, in the present embodiment, since the thin portion 24 and the thick portion 25 are formed by changing the thickness of the flexible substrate 20, it is possible to prevent the occurrence of internal stress due to deformation or temperature change of the thin film transistor substrate 1. For example, when the flexible substrate 20 is formed by providing a member for reducing flexibility, since it is necessary to bond members of different materials, internal stress may be generated due to a difference in thermal expansion coefficient or the like, and cracks or chipping may occur in the thin film transistor substrate. In addition, since the thermal expansion coefficients of the respective members are different, the thin film transistor substrate may be wrinkled or deformed. In contrast, in the present embodiment, since only one material is used for the flexible substrate 20, such a problem can be prevented from occurring.

In addition, according to the present embodiment, the recessed portion 23 is formed in a band shape substantially along the y direction, whereby deformation such as winding or bending of the thin film transistor substrate 1 in the x direction becomes easy, and the convenience of use as a flexible display can be improved. Further, since the thickness t2 of the thick portion 25 is twice or more the thickness t1 of the thin portion 24, deformation of the thick portion 25, that is, a force applied to the TFTs 12 and 13 can be suppressed.

In addition, according to the present embodiment, since the arc shapes 23a and 23b are formed at the corner portions of the thin-walled portion 24 and the thick-walled portion 25, the thin-film transistor substrate 1 is not scraped at the edge when the thin-film transistor substrate 1 is wound or the like. Further, since the front surface 21 side of the concave portion 23 is shorter than the rear surface 22 side when cut along the surfaces in the x direction and the z direction, the facing wall surfaces of the concave portion 23 are less likely to come into contact when the thin film transistor substrate 1 is deformed substantially in the x direction, and generation of dust can be prevented.

In addition, according to the present embodiment, in the manufacture of the thin film transistor substrate 1, since the convex portion 51 and the concave portion 52 are formed on the upper surface of the carrier glass 50 (step S1), and the resin film to be the flexible substrate 20 is formed on the upper surface of the carrier glass 50 so as to cover the convex portion 51 and the concave portion 52 (step S2), the thin portion 24 and the thick portion 25 can be formed on the flexible substrate 20 without additionally performing processing on the flexible substrate 20. By manufacturing the thin film transistor substrate 1 in this manner, the shape of the concave portion 23 when cut along the surfaces in the x direction and the z direction is made substantially rectangular in shape with the front surface 21 side shorter than the rear surface 22 side, and the arcuate shapes 23a and 23b are easily formed at the corner portions of the thin portion 24 and the thick portion 25.

Further, by forming an alignment mark on the upper surface of the carrier glass 50 or the flexible substrate 20, the positions of the convex portion 51 and the concave portion 52, that is, the positions where the TFTs should be formed can be grasped when forming the TFTs.

In the present embodiment, the bottom gate TFT in which the source electrode 64 and the drain electrode 65 are formed on the upper side of the gate electrode 61 (the side opposite to the flexible substrate 20) is formed, but the top gate TFT in which the gate electrode 61 is formed on the upper side of the source electrode 64 and the drain electrode 65 may be formed.

In addition, although the present embodiment has been described using an example in which the organic EL is provided on the thin film transistor substrate 1, when liquid crystal is provided on the thin film transistor substrate 1, a part of the steps is not necessary. For example, a base layer, particularly a gas barrier layer, formed on the upper side of the flexible substrate 20 is not necessary. Further, the TFT protecting layer 66 is also different in shape, and the step of injecting the acrylic resin 68 (step S37) is not required.

In the present embodiment, thin portion 24 and thick portion 25 are formed in a substantially strip shape along the y direction, but the arrangement of thin portion 24 and thick portion 25 is not limited to this. For example, the thick portions 25 may be formed into a strip shape by forming the thick portions 25 having a substantially rectangular shape at positions overlapping with the TFTs 12, 13 when viewed from the z direction and disposing the thick portions 25 adjacent to each other substantially in the y direction. In addition, although the TFTs 12 and 13 are provided substantially in the y direction in this embodiment, the arrangement of the TFTs 12 and 13 is not limited to this. For example, the TFTs 12, 13 may also be staggered.

While the embodiments of the present invention have been described in detail with reference to the drawings, the specific configurations are not limited to the embodiments, and design changes and the like are included without departing from the scope of the present invention.

In the present invention, "substantially" means not only strictly the same but also includes a concept of an error or a deformation to the extent that the identity is not lost. For example, the substantially rectangular shape is not limited to the case of being strictly rectangular. For example, when the expression "in the y direction" is abbreviated, not only the case where the expression is strictly in the y direction but also the case where the expression is substantially in the y direction, for example, the case where the expression is in a direction having an error of several degrees with respect to the y direction.

Description of the reference numerals

1: thin film transistor substrate

10: sub-pixel

11: pixel electrode

12、13 ：TFT

14: holding capacitor

15. 16, 17: wiring

20: flexible substrate

21: front side

22: back side of the panel

23: concave part

23a, 23 b: arc shape

24: thin wall part

25: thick wall part

50: carrier glass

51: convex part

51a, 51 b: arc shape

52: concave part

53: alignment mark

55: adhesive layer

61: grid electrode

62: gate insulating layer

63: polycrystalline silicon layer

64: source electrode

65: drain electrode

66: TFT protective layer

66 a: concave part

67: ITO film

68: acrylic resin.