Etchant compositions and methods of manufacturing integrated circuit devices using the same

Patent metadata

Field	Value
Publication number	US-11437246-B2
Application number	US-202017008736-A
Country	US
Kind code	B2
Filing date	Sep 1, 2020
Priority date	Dec 27, 2019
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

Etchant compositions described herein include etchant compositions for etching a silicon film and may include nitric acid, fluoric acid, phosphoric acid, acetic acid, a nitrogen compound, and water. The nitrogen compound may include fluorine (F), phosphorus (P), and/or carbon (C). Also described are methods of manufacturing an integrated circuit (IC) device. The methods may include providing a structure in which a silicon film doped at a first dopant concentration and an epitaxial film doped at a second dopant concentration are stacked. The second dopant concentration may be different from the first dopant concentration. The silicon film may be selectively etched from the structure by using an etchant composition.

First claim

What is claimed is:

1. An etchant composition consisting essentially of: nitric acid in an amount of 10% to 20% by weight of the etchant composition; fluoric acid in an amount of 1% to 15% by weight of the etchant composition; phosphoric acid in an amount of 5% to 30% by weight of the etchant composition;
acetic acid in an amount of 10% to 50% by weight of the etchant composition; a nitrogen compound in an amount of 0.5% to 10% by weight of the etchant composition; and
water;
wherein the nitrogen compound comprises ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, urea, urea phosphate, urea nitrate, imidazolidinyl urea, phenylurea, 1,1-diphenyl urea, 1,3-diphenyl urea, hydroxyurea, 1,1-dimethyl urea, or a combination thereof.

2. The etchant composition of claim 1 , wherein the nitrogen compound comprises ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, or a combination thereof.

3. The etchant composition of claim 1 , wherein the nitrogen compound comprises urea, urea phosphate, urea nitrate, imidazolidinyl urea, phenylurea, 1,1-diphenyl urea, 1,3-diphenyl urea, hydroxyurea, 1,1-dimethyl urea, or a combination thereof.

4. The etchant composition of claim 1 , wherein the etchant composition is configured to etch a single-crystalline silicon film doped with a P-type dopant.

5. The etchant composition of claim 1 , wherein the etchant composition is configured to etch a silicon film that is doped with boron (B) atoms at a concentration of 1.0×10 17 atoms/cm 3 to 5.0×10 18 atoms/cm 3 .

6. The etchant composition of claim 1 , wherein a weight percent of the nitrogen compound is lower than a weight percent of each of the nitric acid, the fluoric acid, the phosphoric acid, and the acetic acid.

7. The etchant composition of claim 1 , wherein each of a weight percent of the nitric acid, a weight percent of the phosphoric acid, and a weight percent of the acetic acid is at least twice a weight percent of the nitrogen compound.

8. The etchant composition of claim 1 , wherein a weight percent of the nitric acid is lower than a weight percent of the acetic acid.

Assignees

• Samsung Electronics Co Ltd
• Samyoung Pure Chemicals Co Ltd

Inventors

• Kim Youngchan
• Kim Youngtak
• Kim Jungah
• Han Hoon
• Baek Geunjoo
• Ihn Chisung
• Yun Sangmoon

Classifications

• H10P50/642 Primary

  Chemical etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/667 Primary

  by liquid etching only · CPC title

• H10F99/00

  Subject matter not provided for in other groups of this subclass · CPC title

• C09K13/08 Primary

  containing a fluorine compound · CPC title