Atomic layer etching processes

Patent metadata

Field	Value
Publication number	US-11640899-B2
Application number	US-202117452156-A
Country	US
Kind code	B2
Filing date	Oct 25, 2021
Priority date	Dec 22, 2016
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

Atomic layer etching (ALE) processes are disclosed. In some embodiments, the methods comprise at least one etch cycle in which the substrate is alternately and sequentially exposed to a first vapor phase non-metal halide reactant and a second vapor phase halide reactant. In some embodiments both the first and second reactants are chloride reactants. In some embodiments the first reactant is fluorinating gas and the second reactant is a chlorinating gas. In some embodiments a thermal ALE cycle is used in which the substrate is not contacted with a plasma reactant.

First claim

What is claimed is:

1. A method of etching a film on a substrate in a reaction chamber by chemical atomic layer etching, the method comprising one or more etching cycles comprising:
exposing the substrate to a first vapor-phase oxyhalide reactant; and
moving the substrate to remove excess first vapor-phase oxyhalide halide reactant from the vicinity of the substrate, wherein the first vapor-phase oxyhalide reactant does not comprise metal, wherein the substrate is not contacted with a plasma reactant during the etching cycle, and wherein each etching cycle removes material from the film.

2. The method of claim 1 , further comprising exposing the substrate to a vapor-phase metal or semi-metal halide reactant.

3. The method of claim 2 , wherein the vapor-phase metal or semi-metal halide reactant comprises Te, Sb, As, Nb, Ta, Mo, Sn, V, Re, Te, W or a group 6 transition metal.

4. The method of claim 2 , wherein the vapor phase metal or semi-metal halide reactant comprises sulfur atoms.

5. The method of claim 2 , wherein the vapor phase metal or semi-metal halide reactant comprises oxygen atoms.

6. The method of claim 1 , further comprising exposing the substrate to a second vapor-phase oxyhalide reactant.

7. The method of claim 6 , wherein the etching cycle additionally comprises exposing the substrate to a third vapor-phase reactant that is different from the first and second vapor-phase oxyhalide reactants.

8. The method of claim 7 , wherein the third vapor-phase reactant comprises trimethylaluminum (TMA), Hacac, Sn(acac) 2 , Hhfac H 2 O 2 , HCOOH, H 2 O, O 2 or O 3 .

9. The method of claim 7 , where the third vapor phase reactant comprises an adduct forming compound.

10. The method of claim 7 , wherein the third vapor phase reactant comprises CS 2 , CH 3 CN, NH 3 , SO 3 , tris(2-aminoethyl)amine, triethanolamine, pyridine, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), tetrahydrothiophene, 1, 4-dioxane, an isocyanate, a poly-ol, ethanolamine, a sulfone, trichloromethane, an alkyl or substituted isothiocyanate, trichloronitromethane, an alkyl, aryl or substituted nitrile, an isonitrile, a diamine, a dithione, a sulfone, TIPA, TIPEA, TMEA or a heterocylic reactive compound.

11. The method of claim 1 , wherein the first vapor-phase oxyhalide reactant comprises a semi-metal.

12. The method of claim 1 , wherein the first vapor-phase oxyhalide reactant does not comprise hydrogen or carbon.

13. The method of claim 1 , wherein the first vapor-phase oxyhalide reactant comprises sulfur, halide and oxygen atoms.

14. The method of claim 1 , wherein the first vapor-phase oxyhalide reactant comprises halide and nitrogen atoms.

15. The method of claim 1 , wherein the substrate comprises two or more different materials that are exposed to the first vapor-phase oxyhalide reactant and one material is selectively etched relative to the other materials.

16. The method of claim 1 , wherein the film comprises a metal oxide, metal carbide, metal nitride or is an elemental film.

17. The method of claim 16 , wherein the film comprises Ti, Mo, Cu, Co, W, Si, Ta, Al, Zr, Hf, Ge, Pt, Ni, Zn, Nb, Ir, Ru, Rh, or Sb.

18. The method of claim 1 , wherein the substrate is moved to a different reaction chamber.

19. The method of claim 1 , wherein the substrate is moved from a reaction space containing the first vapor-phase oxyhalide reactant to a second, different reaction space.

Assignees

• Asm Ip Holding Bv

Inventors

• Blomberg Tom E
• Sharma Varun
• Haukka Suvi P
• Tuominen Marko J
• Zhu chiyu

Classifications

• H10P50/283

  by chemical means · CPC title

• H10P50/266

  by vapour etching only · CPC title

• C23G5/00

  Cleaning or de-greasing metallic material by other methods; Apparatus for cleaning or de-greasing metallic material with organic solvents · CPC title

• C23F1/12

  Gaseous compositions · CPC title

• H01J37/32009 Primary

  Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources (plasma generation in general H05H1/24) · CPC title