SILICON CARBIDE (SIC) WAFER POLISHING WITH SLURRY FORMULATION AND PROCESS
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.
1 . A composition of matter comprising:
(1) water, (2) 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 (3) a particulate abrasive, wherein the composition of matter has a pH of 2-5.
2 . The composition as recited in claim 1 , wherein the metal ion electrophile is a metal ion selected from the group consisting of Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Fe 3+ , Ti 4+ , V 5+ , Mo 6+ , Cr 6+ and Mn 7+ .
3 . The composition as recited in claim 2 , wherein the ligand is a monoprotic carboxylic acid.
4 . The composition as recited in claim 2 , 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.
5 . The composition as recited in claim 2 , wherein the ligand is a diprotic carboxylic acid.
6 . The composition as recited in claim 2 , wherein the ligand is a diprotic carboxylic acid selected from a group consisting of carbonic acid, itaconic acid, malonic acid and tartaric acid.
7 . The composition as recited in claim 1 , wherein the metal ion electrophile is a metal ion selected from the group consisting of Cu 2+ , Co 3+ and Zn 2+ .
8 . The composition as recited in claim 7 , wherein the ligand is an amino acid.
9 . The composition as recited in claim 7 , wherein the ligand is an amino acid selected from a group consisting of glycine, serine, arginine, cystine and phenylalanine.
10 . The composition as recited in claim 7 , wherein the ligand is a diprotic carboxylic acid.
11 . The composition as recited in claim 1 , further comprising an oxidizing agent.
12 . The composition as recited in claim 11 , wherein the oxidizing agent is hydrogen peroxide.
13 . The composition as recited in claim 11 , wherein the particulate abrasive is alumina.
14 . A composition of matter consisting of:
(1) water, (2) 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 (3) a particulate abrasive, wherein the composition of matter has a pH of 2-5.
15 . The composition as recited in claim 14 , wherein the metal ion electrophile is a metal ion selected from the group consisting of Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ , Fe 3+ , Ti 4+ , V 5+ , Mo 6+ , Cr 6+ and Mn 7+ .
16 . The composition as recited in claim 15 , wherein the ligand is a diprotic carboxylic acid.
17 . The composition as recited in claim 14 , wherein the metal ion electrophile is a metal ion selected from the group consisting of Cu 2+ , Co 3+ and Zn 2+ .
18 . The composition as recited in claim 17 , wherein the ligand is an amino acid.
19 . The composition as recited in claim 14 , wherein the metal ion electrophile is Cu 2+ and the ligand is an amino acid.
20 . A composition of matter consisting of:
(1) water, (2) 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 (3) a particulate abrasive, wherein the composition of matter has a pH of 2-5 and (4) an oxidizing agent.
21 . The composition as recited in claim 20 , wherein the oxidizing agent is hydrogen peroxide.