Use of a composition and a process for selectively etching silicon

Patent metadata

Field	Value
Publication number	US-12525464-B2
Application number	US-202218566245-A
Country	US
Kind code	B2
Filing date	Jun 28, 2022
Priority date	Jul 8, 2021
Publication date	Jan 13, 2026
Grant date	Jan 13, 2026

Abstract

Described herein is a method of using a composition for selectively etching a silicon layer in the presence of a layer including a silicon germanium alloy, the composition including: (a) 4 to 15% by weight of an amine of formula (E1), and (b) water, where XE1, XE2, and XE3 are independently selected from a chemical bond and C1-C6 alkanediyl; YE is selected from N, CRE1, and P; RE1 is selected from H and C1-C6 alkyl.

First claim

The invention claimed is:

1 . A method of using a composition, the method comprising using the composition for selectively etching a silicon layer in the presence of a layer comprising a silicon germanium alloy, the composition comprising:
(a) 4 to 15% by weight of an amine of formula E1

and
(b) water;
wherein
X E1 , X E2 , and X E3 are independently selected from the group consisting of a chemical bond and C 1 -C 6 alkanediyl;
Y E is selected from the group consisting of N, CR E1 , and P; and
R E1 is selected from the group consisting of H and C 1 -C 6 alkyl.

2 . The method according to claim 1 , wherein X E1 is selected from the group consisting of methanediyl, ethane-1,2-diyl, propane-1,3-diyl, and propane-1,2-diyl.

3 . The method according to claim 1 , wherein Y E is N.

4 . The method according to claim 3 , wherein the amine is tris-(2-aminoethyl)amine (TREN) or tris-(3-aminopropyl)amine.

5 . The method according to claim 1 , wherein Y E is CR E1 .

6 . The method according to claim 5 , wherein R E1 is selected from the group consisting of H and methyl, ethyl, propyl, and butyl, which are unsubstituted or substituted by NH 2 .

7 . The method according to claim 5 , wherein the amine is selected from the group consisting of 2-(aminomethyl)-2-methyl-1,3-propandiamine, and 3-(aminoethyl)-3-ethyl-1,5-pentandiamine.

8 . The method according to claim 1 , further comprising an organic solvent miscible with water.

9 . The method according to claim 8 , wherein the solvent is (a) a C 1 to C 6 alkanolamine; (b) a polyhydric alkanol; or (c) a combination thereof.

10 . The method according to claim 8 , wherein the solvent is (a) ethanolamine, diethanolamine or triethanolamine; (b) a diol or triol; or (c) a combination thereof.

11 . The method according to claim 1 , wherein the composition consists essentially of:
(a) 4 to 15% by weight of the amine; (b) 0 to 50% by weight of an organic solvent; (c) 0 to 3% by weight of a surfactant; (d) 0 to 3% by weight of a chelating agent; and (e) water.

12 . The method according to claim 1 , wherein the composition consists essentially of the amine and water.

13 . The method according to claim 1 , wherein the composition has a pH of 10 to 13.

14 . The method according to claim 1 , wherein the composition has a pH of 11 to 12.5.

15 . A process of selectively removing a silicon layer from a surface of a microelectronic device relative to a layer comprising a silicon-germanium alloy, the process comprising:
(a) providing a microelectronic device surface that includes the silicon layer and the layer comprising the silicon germanium alloy; (b) providing an etching composition comprising (i) 4 to 15% by weight of an amine of formula E1

and
(ii) water;
wherein
X E1 , X E2 , and X E3 are independently selected from the group consisting of a chemical bond and C 1 -C 6 alkanediyl;
Y E is selected from the group consisting of N, CR E1 , and P; and
R E1 is selected from the group consisting of H and C 1 -C 6 alkyl; and
(c) contacting the surface with the composition for a time and at a temperature effective to selectively remove the silicon layer relative to the layer comprising the silicon-germanium alloy.

16 . A process for the manufacture of a semiconductor device, comprising selectively removing silicon from a surface of a microelectronic device relative to a silicon-germanium containing material according to claim 15 .

Assignees

• Basf Se

Inventors

• Lopez Villanueva Francisco Javier
• Hildebrandt Sven
• Klipp Andreas

Classifications

• H10P50/644 Primary

  Anisotropic liquid etching (H10P50/61 takes precedence) · CPC title

• H10P50/642

  Chemical etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/282

  of inorganic materials · CPC title

• H10P50/264

  by chemical means · CPC title