Extreme ultraviolet (euv) activated underlayer

Patent metadata

Field	Value
Publication number	US-2025385101-A1
Application number	US-202519215201-A
Country	US
Kind code	A1
Filing date	May 21, 2025
Priority date	Jun 17, 2024
Publication date	Dec 18, 2025
Grant date	—

Abstract

Embodiments described herein relate to a method that includes forming a patterning stack over a substrate, wherein the patterning stack includes an underlayer over the substrate that includes an extreme ultraviolet (EUV) sensitive material with —OH terminated chains, and a resist layer over the underlayer. The method further includes exposing regions of the patterning stack with EUV electromagnetic radiation, and increasing a temperature of the patterning stack, wherein OH and/or H2O is released from exposed regions of the underlayer and diffuses into the resist layer. The method may also include developing the resist layer.

First claim

What is claimed is:

1 . A method, comprising:
forming a patterning stack over a substrate, wherein the patterning stack comprises:
an underlayer over the substrate, wherein the underlayer comprises an extreme ultraviolet (EUV) sensitive material with —OH terminated chains; and
a resist layer over the underlayer;
exposing regions of the patterning stack with EUV electromagnetic radiation; releasing OH and/or H 2 O from exposed regions of the underlayer and diffusing the OH and/or H 2 O into the resist layer; and developing the resist layer.

2 . The method of claim 1 , wherein the underlayer comprises silicon, oxygen, carbon, and hydrogen.

3 . The method of claim 1 , wherein the underlayer is a curable polymer.

4 . The method of claim 1 , wherein a temperature of the patterning stack is increased to at least 160° C.

5 . The method of claim 1 , wherein the underlayer and the resist layer are formed with a chemical vapor deposition (CVD) process.

6 . The method of claim 5 , further comprising:
transferring a pattern of the developed resist layer into the underlayer with an etching process.

7 . The method of claim 6 , wherein the CVD process and the etching process are implemented in a single cluster tool.

8 . The method of claim 1 , wherein the resist layer comprises a metal oxide resist (MOR).

9 . The method of claim 1 , wherein unexposed regions of the underlayer do not release OH and/or H 2 O.

10 . The method of claim 1 , wherein nitrogen is not integrated into the underlayer.

11 . A patterning stack for extreme ultraviolet (EUV) lithography, comprising:
a substrate; an underlayer over the substrate, wherein the underlayer comprises a first EUV sensitive material with —OH terminated chains; and a resist layer over the underlayer, wherein the resist layer is a second EUV sensitive material.

12 . The patterning stack of claim 11 , wherein the underlayer comprises silicon, oxygen, carbon, and hydrogen.

13 . The patterning stack of claim 11 , wherein the underlayer is a curable polymer.

14 . The patterning stack of claim 11 , wherein the resist layer is a metal oxide resist (MOR).

15 . The patterning stack of claim 11 , wherein the underlayer is substantially free of nitrogen.

16 . The patterning stack of claim 11 , wherein the underlayer releases OH and/or H 2 O in response to EUV exposure.

17 . The patterning stack of claim 11 , wherein the underlayer is cross-linked during EUV exposure through a silanol condensation process.

18 . A method, comprising:
forming a patterning stack over a substrate, wherein the patterning stack comprises:
an underlayer over the substrate, wherein the underlayer comprises an extreme ultraviolet (EUV) sensitive material comprising silicon, oxygen, carbon, and hydrogen with —OH terminated chains; and
a resist layer over the underlayer, wherein the resist layer is a metal oxide resist (MOR);
exposing regions of the patterning stack with EUV electromagnetic radiation; curing the patterning stack, wherein exposure and curing drives a silanol condensation cross-linking process in the underlayer that releases OH and/or H 2 O that diffuses into the resist layer; and developing the resist layer.

19 . The method of claim 18 , further comprising:
transferring a pattern in the developed resist layer into the underlayer with an etching process.

20 . The method of claim 18 , wherein the curing includes bringing a temperature of the patterning stack to at least 160° C.

Assignees

• Applied Materials Inc

Inventors

• Fung Nancy
• Lang Chi-I
• Stolfi Michael
• Kanzawa Hideyuki
• Liu Lequn

Classifications

• H10P50/73 Primary

  using masks for insulating materials · CPC title

• G03F1/22

  Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof · CPC title

• G03F7/70033

  by plasma extreme ultraviolet [EUV] sources · CPC title

• G03F7/167 Primary

  from the gas phase, by plasma deposition (G03F7/2035 takes precedence) · CPC title

• H01L21/31144 Primary

  Electricity · mapped topic