Film stack for lithography applications

Patent metadata

Field	Value
Publication number	US-11495461-B2
Application number	US-202016800351-A
Country	US
Kind code	B2
Filing date	Feb 25, 2020
Priority date	Feb 25, 2019
Publication date	Nov 8, 2022
Grant date	Nov 8, 2022

Abstract

Methods for forming a film stack comprising a hardmask layer and etching such hardmask layer to form features in the film stack are provided. The methods described herein facilitate profile and dimension control of features through a proper profile management scheme formed in the film stack. In one or more embodiments, a method for etching a hardmask layer includes forming a hardmask layer on a substrate, where the hardmask layer contains a metal-containing material containing a metal element having an atomic number greater than 28, supplying an etching gas mixture to the substrate, and etching the hardmask layer exposed by a photoresist layer.

First claim

What is claimed is:

1. A method for etching a hardmask layer, comprising:
forming a hardmask layer on a substrate, wherein the hardmask layer comprises a metal-containing material comprising a metal element having an atomic number of greater than 28; wherein the hardmask layer is disposed on a bottom anti-reflective coating layer disposed on a dielectric multi-layer, and wherein the bottom anti-reflective coating layer is an amorphous carbon layer and the dielectric multi-layer comprises at least a silicon containing dielectric layer and a metal dielectric layer;
supplying an etching gas mixture to the substrate, further comprising:
supplying a deposition gas mixture to the substrate; and
forming a passivation layer on a top surface of a photoresist layer disposed on the hardmask layer; and

etching the hardmask layer exposed by the photoresist layer, wherein the etching further comprises pulsing an RF power while etching the hardmask layer.

2. The method of claim 1 , wherein the metal-containing material further comprises silicon and oxygen, and wherein the metal-containing material comprises about 80 atomic percent (at %) to about 90 at % of the metal element.

3. The method of claim 1 , further comprising an organic layer disposed between the bottom anti-reflective coating layer and the photoresist layer.

4. The method of claim 1 , wherein the metal element is selected from the group consisting of tin, indium, gallium, zirconium, zinc, and any combination thereof.

5. The method of claim 1 , wherein the metal-containing material comprises tin oxide, tin silicon oxide, indium tin oxide, indium gallium zinc oxide, an alloy thereof, or any combination thereof.

6. The method of claim 1 , wherein the hardmask layer comprises multiple layers.

7. The method of claim 6 , wherein an upper portion of the hardmask layer comprises has a greater concentration of the metal element than a lower portion of the hardmask layer.

8. The method of claim 6 , wherein the hardmask layer comprises at least two layers having different absorption coefficients.

9. The method of claim 8 , wherein the hardmask layer comprises a first layer comprising an element having the atomic number greater than 28 and a second layer comprising an element having an atomic number less than 28.

10. The method of claim 6 , wherein the hardmask layer comprises a first layer comprising a first metal element, a second layer comprising a second metal element, and a third layer comprising a third metal element, and wherein the second metal element has an atomic number greater than or less than the first or third metal element.

11. The method of claim 1 , wherein the hardmask layer is a gradient layer having different metal element concentration through the hardmask layer.

12. The method of claim 1 , wherein the photoresist layer comprises at least one metal element selected from the group consisting of tin, indium, gallium, zirconium, zinc, and any combination thereof.

13. The method of claim 1 , wherein forming the hardmask layer further comprises:
forming a plasma comprising Xe or Kr while forming the hardmask layer.

14. The method of claim 1 , wherein supplying the etching gas mixture further comprises supplying a chlorine-containing gas or a bromine-containing gas to etch the hardmask layer.

15. A method for etching a hardmask layer, comprising:
forming a hardmask layer on a substrate, wherein the hardmask layer comprises a metal-containing material comprising a metal element having an atomic number of greater than 28; wherein the metal-containing material further comprises silicon and oxygen, and wherein the metal-containing material comprises about 80 atomic percent (at %) to about 90 at % of the metal element; wherein the hardmask layer is disposed on a bottom anti-reflective coating layer disposed on a dielectric multi-layer, and wherein the bottom anti-reflective coating layer is an amorphous carbon layer and the dielectric multi-layer comprises at least a silicon containing dielectric layer and a metal dielectric layer;
forming a passivation layer on a surface of a photoresist layer disposed on the hardmask layer, wherein the hardmask layer comprises tin oxide, tin silicon oxide, indium tin oxide, indium gallium zinc oxide, an alloy thereof, or any combination thereof; and
supplying an etching gas mixture to the substrate, further comprising:
supplying a deposition gas mixture to the substrate; and
forming a passivation layer on a top surface of a photoresist layer disposed on the hardmask layer; and

etching the hardmask layer exposed by the photoresist layer, wherein the hardmask layer is etched by a gas mixture comprising a chlorine-containing gas or a bromine-containing gas.

16. The method of claim 15 , wherein the hardmask layer comprises at least two layers having different absorption coefficients.

17. The method of claim 15 , wherein an upper portion of the hardmask layer comprises has a greater concentration of the metal element than a lower portion of the hardmask layer.

18. The method of claim 15 , further comprising an organic layer disposed between the bottom anti-reflective coating layer and the photoresist layer.

19. A method for etching a hardmask layer, comprising:
forming a hardmask layer on a substrate, wherein the hardmask layer comprises a metal-containing material comprising a metal element having an atomic number of greater than 28; wherein the hardmask layer is disposed on a bottom anti-reflective coating layer disposed on a dielectric multi-layer, and wherein the bottom anti-reflective coating layer is an amorphous carbon layer and the dielectric multi-layer comprises at least a silicon containing dielectric layer and a metal dielectric layer;
supplying an etching gas mixture to the substrate, further comprising:
supplying a deposition gas mixture to the substrate; and
forming a passivation layer on a top surface of a photoresist layer disposed on the hardmask layer; and

etching the hardmask layer exposed by the photoresist layer, wherein the hardmask layer is etched by a gas mixture comprising a chlorine-containing gas or a bromine-containing gas, wherein the etching further comprises pulsing an RF power while etching the hardmask layer, and wherein the hardmask layer comprises at least two layers having different absorption coefficients.

20. The method of claim 19 , further comprising an organic layer disposed between the bottom anti-reflective coating layer and the photoresist layer.

Assignees

• Applied Materials Inc

Inventors

• Singh Tejinder
• Parikh Suketu Arun
• Diehl Daniel Lee
• Stolfi Michael Anthony
• Ramalingam Jothilingam
• Cao Yong
• Yan Lifan
• Lang Chi-I
• Hwang Hoyung David

Classifications

• H10P76/405

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

• H10P50/285

  of materials not containing Si, e.g. PZT or Al2O3 · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P76/4085 Primary

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

• H10P50/267

  using plasmas · CPC title