IP Library › Granted Patent US 12,448,545
Granted Patent B2
US 12,448,545 · App. 18/556,230 · Granted Oct 21, 2025

Silicon carbide (SIC) wafer polishing with slurry formulation and process

Inventors: Ara Philipossian (Tucson, AZ); Yasa Sampurno (Tucson, AZ); Jason A. Keleher (Naperville, IL); Katherine Wortman-Otto (Minneapolis, MN); Abigail Linhart (Harvard, IL); Kiana A. Cahue (Joliet, IL)
Assignee: Araca, Inc.
C09G1/02
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Quick Facts
Patent No.
US 12,448,545
App. No.
18/556,230
Granted
Oct 21, 2025
Kind
B2
Abstract

A method for polishing a silicon carbide surface. The silicon carbide surface is polished with a particulate abrasive while exposed to a composition of water, an oxidizing agent and an electrophile.

Claims (25)

1. A method for polishing a silicon carbide surface, the method comprising:

exposing a silicon carbide surface to a composition with a pH of 2-5, the composition comprising (1) water (2) an oxidizing agent (3) a metal ion electrophile with a ligand, the metal ion electrophile present in a concentration between 0.005 wt % and 0.05 wt %, based on a total weight of the composition, and the ligand being present in a metal:ligand weight ratio between 1:8 and 1:12, and (4) a particulate abrasive;

and

polishing the silicon carbide surface while the silicon carbide surface is exposed to the composition.

2. The method as recited in claim 1 , wherein the oxidizing agent is hydrogen peroxide.

3. The method as recited in claim 1 , wherein the metal ion electrophile is a divalent metal ion selected from a group consisting of Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Cu 2+ , Zn 2+ .

4. The method as recited in claim 1 , wherein the metal ion electrophile is Cu 2+ .

5. The method as recited in claim 1 , wherein the metal ion electrophile is selected from a group consisting of Fe 3+ , Co 3+ , Ti 4+ , V 4+ , V 5+ , Cr 6+ , Mo 6+ and Mn 7+ .

6. The method as recited in claim 1 , wherein the metal ion electrophile is selected from a group consisting of Co 3+ , Ti 4+ , V 4+ , V 5+ , Cr 6+ , Mo 6+ and Mn 7+ .

7. The method as recited in claim 1 , wherein the metal ion electrophile is V 4+ or V 5+ .

8. The method as recited in claim 1 , wherein the ligand is an amino acid.

9. The method as recited in claim 1 , wherein the ligand is an amino acid selected from a group consisting of glycine, serine, arginine, cystine and phenylalanine.

10. The method as recited in claim 1 , wherein the ligand is a monoprotic carboxylic acid.

11. The method as recited in claim 1 , wherein the ligand is a monoprotic carboxylic acid selected from a group consisting of formic acid, acetic acid, glycolic acid, propionic acid, butanoic acid, hexanoic acid, heptanoic acid, octanoic acid, decanoic acid, pyruvic acid and t-cinnamic acid.

12. The method as recited in claim 1 , wherein the ligand is a diprotic carboxylic acid.

13. The method as recited in claim 1 , wherein the ligand is a diprotic carboxylic acid selected from a group consisting of carbonic acid, itaconic acid, malonic acid and tartaric acid.

14. The method as recited in claim 1 , wherein the ligand is tartaric acid.

15. The method as recited in claim 1 , wherein the ligand is a carbamate.

16. The method as recited in claim 1 , wherein the ligand is a hydroxamic acid or a hydroxamic ester.

17. The method as recited in claim 1 , wherein the ligand is a hydroxamic acid or a hydroxamic ester selected from a group consisting of suberohydroxamic acid, salicylhydroxamic acid and ethyl acetohydroxamate.

18. The method as recited in claim 1 , wherein the ligand is an aliphatic amide.

19. The method as recited in claim 1 , wherein the ligand is hydroxyurea.

20. The method as recited in claim 1 , wherein the composition consists of the water, the oxidizing agent, the metal ion electrophile with ligand and the particulate abrasive.

21. The method as recited in claim 1 , wherein the oxidizing agent is hydrogen peroxide, the metal ion electrophile is V 4+ , and the ligand is tartaric acid.

22. The method as recited in claim 1 , wherein oxidizing agent is hydrogen peroxide, the metal ion electrophile is Cu 2 +and the ligand is an amino acid.

Assignments (2)
CHANGE OF ADDRESS Recorded Nov 21, 2025
From: ARACA, INC.
To: ARACA, INC.
Reel/Frame 073665/0020 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 20, 2023
From: WORTMAN-OTTO, KATHERINE; SAMPURNO, YASA; CAHUE, KIANA A.; KELEHER, JASON J.; LINHART, ABIGAIL; PHILIPOSSIAN, ARA
To: ARACA, INC.
Reel/Frame 065295/0817 →
Continuity (2)
Provisional Application 63188305 · May 13, 2021
Related Publication 20240191101A1 · Jun 13, 2024
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