Method for manufacturing thin film transistor, method for manufacturing array substrate, array substrate and display device

1. A method for manufacturing a thin film transistor, comprising:

forming an intermediate layer on a substrate;

patterning the intermediate layer to form an intermediate layer reserved region and an intermediate layer unreserved region, wherein the intermediate layer unreserved region corresponds to a pattern of a first structure layer;

forming, on the substrate with a pattern of the intermediate layer, a material layer from which the first structure layer is formed; and

removing the intermediate layer, and forming the pattern of the first structure layer through a portion of the material layer remaining on the substrate,

wherein the intermediate layer reserved region has a surface with a concave-convex structure, and

a material of the intermediate layer comprises a photoresist.

2. The method according to claim 1 , wherein a height difference between a convex portion and a concave portion of the concave-convex structure is larger than a thickness of the first structure layer.

3. The method according to claim 1 , wherein the first structure layer is an active layer.

4. The method according to claim 3 , wherein the intermediate layer is a positive photoresist, and the step of forming the intermediate layer reserved region comprises:

exposing the intermediate layer by a grey tone mask plate comprising an opaque region, a semi-transparent region and a transparent region; and

forming, after a developing process, a first portion of the intermediate layer reserved region corresponding to the opaque region, a second portion of the intermediate layer reserved region corresponding to the semi-transparent region and the intermediate layer unreserved region corresponding to the transparent region, wherein a thickness of the first portion is larger than a thickness of the second portion.

5. The method according to claim 3 , wherein the intermediate layer is a negative photoresist, and the step of forming the intermediate layer reserved region comprises:

exposing the intermediate layer by a grey tone mask plate comprising an opaque region, a semi-transparent region and a transparent region; and

forming, after a developing process, a first portion of the intermediate layer reserved region corresponding to the transparent region, a second portion of the intermediate layer reserved region corresponding to the semi-transparent region and the intermediate layer unreserved region corresponding to the opaque region, wherein a thickness of the first portion is larger than a thickness of the second portion.

6. The method according to claim 3 , wherein the step of removing the intermediate layer comprises:

applying a stripping liquid onto an exposed portion of the intermediate layer, and removing the intermediate layer from the substrate through a chemical reaction between the stripping liquid and the intermediate layer.

7. The method according to claim 1 , wherein a material of the material layer comprises a-Si and N+a-Si.

8. The method according to claim 1 , wherein prior to forming an intermediate layer on a substrate, the method further comprises:

providing a base substrate;

forming a pattern of a gate metal layer on the substrate; and

depositing a gate insulating layer onto the base substrate provided with the pattern of the gate metal layer.

9. A method for manufacturing an array substrate, comprising forming a thin film transistor on a substrate by the method according to claim 1 .

10. An array substrate, comprising a thin film transistor formed on a substrate by the method according to claim 1 .

11. A display device, comprising the array substrate according to claim 10 .

12. The method according to claim 1 , wherein prior to forming an intermediate layer on a substrate, the method further comprises:

providing a base substrate;

forming a pattern of a gate metal layer on the substrate; and

depositing a gate insulating layer onto the base substrate provided with the pattern of the gate metal layer.

13. A method for manufacturing a thin film transistor, comprising:

providing a substrate;

forming a pattern of a gate metal layer on the substrate;

depositing a gate insulating layer onto the substrate provided with the pattern of the gate metal layer;

coating a first intermediate layer on the substrate;

exposing the first intermediate layer and forming, after a developing process, a first intermediate layer unreserved region corresponding to a pattern of a first structure layer and a first intermediate layer reserved region corresponding to other regions;

depositing the first structure layer on the substrate;

depositing a second intermediate layer on the substrate;

exposing the second intermediate layer, and forming, after a developing process, a second intermediate layer reserved region corresponding to the pattern of the first structure and a second intermediate layer unreserved region corresponding to the other regions;

removing the first structure layer at the second intermediate layer unreserved region by a dry etching process, to form a pattern of the first structure layer; and

applying a stripping liquid onto the second intermediate layer to remove the first intermediate layer and the second intermediate layer,

wherein the intermediate layer reserved region has a surface with a concave-convex structure, and

each of a material of the first intermediate layer and a material of the second intermediate layer comprises a photoresist.

14. The method according to claim 13 , wherein the first structure layer is an active layer.

15. The method according to claim 14 , wherein the intermediate layer is a positive photoresist, and the step of forming the intermediate layer reserved region comprises:

exposing the intermediate layer by a grey tone mask plate comprising an opaque region, a semi-transparent region and a transparent region; and

forming, after a developing process, a first portion of the intermediate layer reserved region corresponding to the opaque region, a second portion of the intermediate layer reserved region corresponding to the semi-transparent region and the intermediate layer unreserved region corresponding to the transparent region, wherein a thickness of the first portion is larger than a thickness of the second portion.

16. The method according to claim 14 , wherein the intermediate layer is a negative photoresist, and the step of forming the intermediate layer reserved region comprises:

exposing the intermediate layer by a grey tone mask plate comprising an opaque region, a semi-transparent region and a transparent region; and

forming, after a developing, a first portion of the intermediate layer reserved region corresponding to the transparent region, a second portion of the intermediate layer reserved region corresponding to the semi-transparent region and the intermediate layer unreserved region corresponding to the opaque region, wherein a thickness of the first portion is larger than a thickness of the second portion.