Method for performing a photolithography process

• US 10,573,519 B2
• Filed: 02/27/2018
• Issued: 02/25/2020
• Est. Priority Date: 09/08/2017
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Ko, Tsung-Han, Cheng, Joy, Chang, Ching-Yu, Lin, Chin-Hsiang
• Primary Examiner(s): Mulpuri, Savitri
• Application Number:
  US15/906,187
• Publication Number:
  US 20190080901A1
• Time in Patent Office: 728 Days
• CPC Class Codes: G03F 7/038 Macromolecular compounds which are rendered insoluble or differentially wettable G03F7/075 takes precedence; macromolecular azides G03F7/012; macromolecular diazonium compounds G03F7/021
• CPC Class Codes: G03F 7/039 Macromolecular compounds which are photodegradable, e.g. positive electron resists G03F7/075 takes precedence; macromolecular quinonediazides G03F7/023
• CPC Class Codes: G03F 7/0392 the macromolecular compound being present in a chemically amplified positive photoresist composition
• CPC Class Codes: G03F 7/094 Multilayer resist systems, e.g. planarising layers
• CPC Class Codes: G03F 7/20 Exposure; Apparatus therefor photographic printing apparatus for making copies G03B27/00
• CPC Class Codes: G03F 7/26 Processing photosensitive materials; Apparatus therefor G03F7/12 - G03F7/24 take precedence
• CPC Class Codes: G03F 7/38 Treatment before imagewise removal, e.g. prebaking G03F7/265 takes precedence
• CPC Class Codes: G03F 7/40 Treatment after imagewise removal, e.g. baking
• CPC Class Codes: G03F 7/405 Treatment with inorganic or organometallic reagents after imagewise removal
• CPC Class Codes: H01L 21/0271 comprising organic layers
• CPC Class Codes: H01L 21/0273 characterised by the treatment of photoresist layers
• CPC Class Codes: H01L 21/0274 Photolithographic processes
• CPC Class Codes: H01L 21/0337 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/266 using masks H01L21/26586 takes precedence
• CPC Class Codes: H01L 21/3086 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment

Abstract

A method for performing a photolithography process is provided. The method includes forming a resist layer over a substrate and exposing a portion of the resist layer to form an exposed region and an unexposed region by performing an exposure process. The method includes performing a baking process on the resist layer, so that voids are formed in the exposed region of the resist layer. The method also includes removing the unexposed region of the resist layer to form a recess in the resist layer and filling a post treatment coating material in the recess and the void. The method further includes removing a portion of the post treatment coating material by performing a second develop process, and another portion of the post treatment coating material is left on surfaces of the exposed region of the resist layer to form a patterned resist layer.

Claims

1. A method for performing a photolithography process, comprising:

forming a resist layer over a substrate;

exposing a portion of the resist layer to form an exposed region and an unexposed region by performing an exposure process;

performing a baking process on the resist layer, so that voids are formed in the exposed region of the resist layer;

filling the void with a post treatment coating material, wherein the post treatment coating material is over the exposed region of the resist layer; and

removing a portion of the post treatment coating material, wherein another portion of the post treatment coating material is left on surfaces of the exposed region of the resist layer to form a patterned resist layer.

2. The method for performing the photolithography process as claimed in claim 1, wherein the another portion of the post treatment coating material is left on a top surface and sidewall surfaces of the exposed region of the resist layer.

3. The method for performing the photolithography process as claimed in claim 1, wherein the post treatment coating material comprises a first segment and a second segment linked to the first segment, and the first segment is configured to form a physical bond or a chemical bond with the exposed region of the resist layer.

4. The method for performing the photolithography process as claimed in claim 3, wherein the first segment comprises a halogen atom, hydroxy group, amine group, sulfo group, or carboxyl group.

5. The method for performing the photolithography process as claimed in claim 3, wherein the second segment is configured to increase the etching resistance of the post treatment coating material, and the second segment comprises substituted or unsubstituted linear, branched, or cyclic hydrocarbon group, or substituted or unsubstituted aromatic group, and/or at least one hydrogen of the unsubstituted linear, branched, or cyclic hydrocarbon group is substituted by halogen, hydroxyl, sulfo or carboxyl.

6. The method for performing the photolithography process as claimed in claim 3, wherein the post treatment coating material further comprises a third segment, and the third segment is configured to increase the resist contrast of the exposed region of the resist layer.

7. The method for performing the photolithography process as claimed in claim 1, further comprising:

performing a post treatment process onto the post treatment coating material before removing the portion of the post treatment coating material.

8. The method for performing the photolithography process as claimed in claim 7, wherein the post treatment process comprises a radiation curing process, a thermal baking process or a combination thereof.

9. The method for performing the photolithography process as claimed in claim 1, wherein the resist layer comprises a polymer and an acid labile group (ALG), and the ALG cleaves from the polymer when performing the baking process on the resist layer.

10. The method for performing the photolithography process as claimed in claim 9, further comprising:

forming a material layer over the substrate;

forming a bottom layer over the material layer;

forming a middle layer over the bottom layer;

forming the resist layer over the middle layer;

patterning the middle layer by using the patterned resist layer as a mask to form a pattered middle layer;

patterning the bottom layer by using the patterned middle layer as a mask to form a patterned bottom layer as a mask; and

performing an etching process or an ion implantation process on the material layer by using the patterned bottom layer as a mask.

11. A method for performing a photolithography process, comprising:

forming a resist layer over a substrate;

exposing a portion of the resist layer to form a first exposed region, a second exposed region and an unexposed region between the first exposed region and the second exposed region;

performing a baking process on the resist layer, so that voids are formed in the first exposed region and the second exposed region;

forming a post treatment coating material over the first exposed region, the second exposed region, an unexposed region and in the voids;

removing a portion of the post treatment coating material by a first developer, wherein another portion of the post treatment coating material is left on a top surface the first exposed region, a top surface of the second exposed region and a top surface of the unexposed region; and

removing the unexposed region using a second developer, wherein another portion of the post treatment coating material is left on the top surface of the first exposed region and the top surface of the second exposed region.

12. The method for performing the photolithography process as claimed in claim 11, wherein the resist layer comprises a polymer and an acid labile group (ALG), and the acid labile group cleaves from the polymer when performing the baking process on the resist layer.

13. The method for performing the photolithography process as claimed in claim 11, further comprising:

forming a second post treatment coating material over the first exposed region and the second exposed region after removing the unexposed region; and

removing a portion of the second post treatment coating material, so that another portion of the second post treatment coating material is left on sidewall surfaces of the first exposed region and the second exposed region of the resist layer.

14. The method for performing the photolithography process as claimed in claim 11, wherein the first developer is different from the second developer.

15. The method for performing the photolithography process as claimed in claim 11, wherein the post treatment coating material comprises a first segment and a second segment linked to the first segment, and the first segment is configured to form a physical bond or a chemical bond with the first exposed region and the second exposed region of the resist layer.

16. A method for performing a photolithography process, comprising:

forming a resist layer over a substrate, wherein the resist layer comprises a polymer and an acid labile group (ALG) linked to the polymer;

exposing a portion of the resist layer to form an exposed region and an unexposed region;

performing a baking process on the resist layer, so that the acid labile group cleaves from the polymer to form voids in the exposed region;

forming a first post treatment coating material over the exposed region and an unexposed region, and in the voids;

removing a portion of the first post treatment coating material, wherein another portion of the first post treatment coating material is left on a top surface of the exposed region and a top surface of the unexposed region; and

removing the unexposed region, wherein another portion of the first post treatment coating material is left on the top surface of the exposed region.

17. The method for performing the photolithography process as claimed in claim 16, further comprising:

forming a second post treatment coating material over the exposed region after removing the unexposed region; and

removing a portion of the second post treatment coating material to form the second post treatment coating material on sidewall surfaces of the exposed region of the resist layer.

18. The method for performing the photolithography process as claimed in claim 16, wherein the step of removing the portion of the first post treatment coating material is performed by a first developer, the step of removing the unexposed region is performed by a second developer, and the first developer is different from the second developer.

19. The method for performing the photolithography process as claimed in claim 16, wherein the voids are formed on outer sidewall surfaces of the exposed region, and the outer sidewall surfaces of the exposed region are covered by the first post treatment coating material.

20. The method for performing the photolithography process as claimed in claim 16, wherein the first post treatment coating material comprises a first segment and a second segment linked to the first segment, and the first segment is configured to form a physical bond or a chemical bond with the exposed region of the resist layer.