Lithography techniques for reducing resist swelling

Patent metadata

Field	Value
Publication number	US-10866517-B2
Application number	US-201916723341-A
Country	US
Kind code	B2
Filing date	Dec 20, 2019
Priority date	Jun 30, 2017
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

The present disclosure provides lithography resist materials and corresponding lithography techniques for improving lithography resolution, in particular, by reducing swelling of resist layers during development. An exemplary lithography method includes performing a treatment process on a resist layer to cause cross-linking of acid labile group components of the resist layer via cross-linkable functional components, performing an exposure process on the resist layer, and performing a development process on the resist layer. In some implementations, the resist layer includes an exposed portion and an unexposed portion after the exposure process, and the treatment process reduces solubility of the unexposed portion to a developer used during the development process by increasing a molecular weight of a polymer in the unexposed portion. The treatment process is performed before or after the exposure process. The treatment process can include performing a thermal treatment and/or an electromagnetic wave treatment to heat the resist layer.

First claim

What is claimed is:

1. A lithography method comprising:
performing a treatment process on a resist layer, the resist layer including acid labile group (ALG) components bonded to cross-linkable functional components, wherein the cross-linkable functional components are cross-linked to one another during the treatment process, and wherein the cross-linkable functional components include at least one of epoxy, alkene, alkyne, methoxyl, glycidyl ether, alkyl oxide, or triazene;
performing an exposure process on the resist layer; and
performing a development process on the resist layer, thereby forming a patterned resist layer.

2. The lithography method of claim 1 , wherein the ALG components are cross-linked to one another via the cross-linking of the cross-linkable functional components.

3. The lithography method of claim 1 , wherein the ALG components include at least one of tert-butoxycarbonyl, methylcyclopentyl, or ethylcyclopentyl.

4. The lithography method of claim 1 , wherein the resist layer further includes cross-linkers to facilitate the cross-linking of the cross-linkable functional components, wherein the cross-linkers include at least one of epoxy, alkene, azide, alkyne, or methoxyl.

5. The lithography method of claim 1 , wherein the resist layer includes an exposed portion and an unexposed portion after the exposure process, and further wherein the treatment process reduces solubility of the unexposed portion to a developer used during the development process by increasing a molecular weight of a polymer in the unexposed portion.

6. The lithography method of claim 5 , wherein the developer removes the exposed portion.

7. The lithography method of claim 1 , wherein the treatment process is performed before performing the exposure process.

8. The lithography method of claim 1 , wherein the treatment process is performed after performing the exposure process.

9. The lithography method of claim 1 , wherein the treatment process includes performing a thermal treatment to heat the resist layer.

10. The lithography method of claim 1 , wherein the treatment process includes performing an electromagnetic wave treatment to heat the resist layer.

11. A lithography method comprising:
exposing a resist layer to patterned radiation, wherein the resist layer includes an exposed portion and an unexposed portion;
treating the resist layer to induce cross-linking of cross-linkable functional components in the unexposed portion, wherein the cross-linkable functional components include at least one of epoxy, alkene, alkyne, methoxyl, glycidyl ether, alkyl oxide, or triazene; and
developing the resist layer to remove the exposed portion, thereby forming a patterned resist layer.

12. The lithography method of claim 11 , wherein the treating of the resist layer induces cross-linking of acid labile group (ALG) components in the unexposed portion, wherein the ALG components include at least one of tert-butoxycarbonyl, methylcyclopentyl, or ethylcyclopentyl.

13. The lithography method of claim 11 , wherein the resist layer further includes cross-linkers to facilitate the cross-linking of the cross-linkable functional components, wherein the cross-linkers include at least one of epoxy, alkene, azide, alkyne, or methoxyl.

14. The lithography method of claim 11 , wherein the treating of the resist layer reduces solubility of the unexposed portion to a developer used during the developing by increasing a molecular weight of a polymer in the unexposed portion.

15. The lithography method of claim 11 , further comprising baking the resist layer.

16. The lithography method of claim 15 , wherein the treating is performed at a first temperature, and the baking is performed at a second temperature, wherein the first temperature is higher than the second temperature.

17. A lithography method comprising:
forming a resist layer, the resist layer including a polymer having acid labile group (ALG) components and cross-linkable functional components bonded thereto, wherein the cross-linkable functional components are bonded to the polymer via the ALG components;
performing a treatment process on the resist layer such that the ALG components are cross-linked to one another via the cross-linkable functional components;
performing an exposure process on the resist layer; and
performing a development process on the resist layer.

18. The lithography method of claim 17 , wherein the polymer includes at least one of poly(norbornene)-co-malaic anhydride, poly(4-hydroxystyrene), phenol-formaldehyde, polyethylene, polypropylene, polycarbonate, polyester, or poly (methyl methacrylate).

19. The lithography method of claim 17 , wherein the cross-linkable functional components include at least one of epoxy, alkene, alkyne, methoxyl, glycidyl ether, alkyl oxide, or triazene.

20. The lithography method of claim 17 , wherein the resist layer further includes cross-linkers to facilitate the cross-linking of the cross-linkable functional components, wherein the cross-linkers include at least one of epoxy, alkene, azide, alkyne, or methoxyl.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Weng Ming-Hui
• Wu Cheng-Han
• Chang Ching-Yu
• Lin Chin-Hsiang

Classifications

• G03F7/0392

  the macromolecular compound being present in a chemically amplified positive photoresist composition · CPC title

• G03F7/40 Primary

  Treatment after imagewise removal, e.g. baking · CPC title

• G03F1/56 Primary

  Organic absorbers, e.g. of photo-resists · CPC title