Method of metal oxide infiltration into photoresist

Patent metadata

Field	Value
Publication number	US-12486559-B2
Application number	US-202217741333-A
Country	US
Kind code	B2
Filing date	May 10, 2022
Priority date	Jun 30, 2021
Publication date	Dec 2, 2025
Grant date	Dec 2, 2025

Abstract

Disclosed herein is a method for forming metal-oxides in the photoresist to improve profile control. The method includes infiltrating a metal oxide in a photoresist layer by pressurizing a methyl-containing material in a processing environment proximate a film stack. The film stack includes the photoresist layer, the photoresist layer being disposed on top of and in contact with an underlayer. The underlayer disposed on top of a substrate. The method includes etching the film stack including the photoresist layer implanted with the metal oxide.

First claim

What is claimed is:

1 . A method for infiltrating a photoresist layer, the method comprising:
heating a methyl-containing material in a processing environment proximate a film stack, the film stack comprising patterned photoresist layers disposed on top of and in contact with an underlayer having a refractive index of between 1.47 and 2.0, wherein a metal oxide and a by-product gas are formed by interaction of the methyl-containing material with an oxidizing agent within the patterned photoresist layers near a top surface of the patterned photoresist layers, wherein the by-product gas diffuses out of the photoresist layer and does not diffuse through the underlayer; and etching portions of the underlayer exposed from the patterned photoresist layers infiltrated with the metal oxide.

2 . The method of claim 1 , further comprising:
absorbing the methyl-containing material through the top surface of the patterned photoresist layers.

3 . The method of claim 2 , wherein the methyl-containing material is absorbed throughout a thickness of the patterned photoresist layers, and the metal oxide is alumina.

4 . The method of claim 1 , further comprising:
maintaining the patterned photoresist layers at a pressure to enable the methyl-containing material to absorb throughout a thickness of the patterned photoresist layers.

5 . The method of claim 4 , wherein the methyl-containing material is subject to a temperature of about 0 degrees to about 150 degrees Celsius, for between about 1 second to about 45 seconds.

6 . The method of claim 1 , wherein the infiltrating of the patterned photoresist layers further comprises:
oxidizing the methyl-containing material in the patterned photoresist layers.

7 . The method of claim 1 , further comprising:
purging the processing environment of the methyl-containing material, prior to oxidizing the methyl-containing material.

8 . The method of claim 7 , further comprising:
maintaining a hydrolysis reaction to oxidize the methyl-containing material in the patterned photoresist layers for a predetermined time between about 1 second and about 400 seconds.

9 . The method of claim 1 , wherein the infiltrating of the patterned photoresist layers further comprises:
oxidizing the methyl-containing material in the patterned photoresist layers; and converting substantially all of the methyl-containing material to alumina.

10 . The method of claim 9 , wherein the film stack is etched with a fluorine-containing gas, or a carbon-fluorine containing gas.

11 . A method for infiltrating a photoresist layer, the method comprising:
pressurizing a methyl-containing material in a processing environment proximate a film stack, the film stack comprising patterned photoresist layers disposed on top of and in contact with an underlayer having a refractive index of between 1.47 and 2.0; heating the methyl-containing material to a predetermined temperature; oxidizing the methyl-containing material in the patterned photoresist layers, wherein a metal oxide and a by-product gas are formed by interaction of the methyl-containing material with an oxidizing agent within the patterned photoresist layers near a top surface of the patterned photoresist layers, wherein the by-product gas diffuses out of the photoresist layer and does not diffuse through the underlayer; and etching portions of the underlayer exposed from the patterned photoresist layers infiltrated with the oxidized methyl-containing material.

12 . The method of claim 11 , further comprising:
maintaining the patterned photoresist layers at a pressure to enable the methyl-containing material to absorb throughout a thickness of the patterned photoresist layers, and the oxidized methyl-containing material is alumina.

13 . The method of claim 12 , wherein the methyl-containing material is subject to a temperature of about 0 degrees to about 150 degrees Celsius, for between about 1 second to about 45 seconds.

14 . The method of claim 11 , further comprising:
purging the processing environment of the methyl-containing material, prior to oxidizing the methyl-containing material.

15 . The method of claim 14 , wherein:
the methyl-containing material in the patterned photoresist layers is oxidized for a predetermined time between about 1 second and about 400 seconds.

16 . The method of claim 11 , wherein:
the oxidizing of the methyl-containing material in the patterned photoresist layers comprises: converting substantially all of the methyl-containing material to alumina, wherein the film stack is etched with a fluorine-containing gas, or a carbon-fluorine containing gas.

17 . A semiconductor processing system, comprising:
a semiconductor processing chamber; and a non-transitory computer readable medium storing instructions, the instructions when executed by a processor cause a method to be performed in the semiconductor processing chamber, the method comprising:
selectively infiltrating patterned photoresist layers with a metal oxide by pressurizing a methyl-containing material in a processing environment proximate a film stack, the film stack comprising the patterned photoresist layers disposed on top of and in contact with an underlayer having a refractive index of between 1.47 and 2.0, wherein a metal oxide and a by-product gas are formed by interaction of the methyl-containing material with an oxidizing agent within the patterned photoresist layers near a top surface of the patterned photoresist layers, wherein the by-product gas diffuses out of the photoresist layers and does not diffuse through the underlayer; and
etching portions of the underlayer exposed from the patterned photoresist layers infiltrated with the metal oxide.

18 . The semiconductor processing system of claim 17 , wherein the infiltrating of the patterned photoresist layers further comprises:
oxidizing the methyl-containing material in the patterned photoresist layers; and converting substantially all of the methyl-containing material to alumina.

19 . The semiconductor processing system of claim 17 , wherein the method further comprises:
heating the patterned photoresist layers at a pressure to enable the methyl-containing material to absorb throughout a thickness of the patterned photoresist layers, and the metal oxide is alumina.

Assignees

• Applied Materials Inc

Inventors

• Fung Nancy
• Saly Mark J

Classifications

• H10P14/68

  Organic materials, e.g. photoresists · CPC title

• H10P76/4085

  characterised by the processes involved to create the masks · CPC title

• H10P76/204 Primary

  of organic photoresist masks · CPC title

• H10P76/405 Primary

  characterised by their composition, e.g. multilayer masks · CPC title

• C23F1/12

  Gaseous compositions · CPC title