US 12,269,969 B2
Polishing composition and method with high selectivity for silicon nitride and polysilicon over silicon oxide
Benjamin Petro, St. Charles, IL (US); Juyeon Chang, Bolingbrook, IL (US); and Brittany Johnson, Wood Dale, IL (US)
Assigned to CMC MATERIALS LLC, Aurora, IL (US)
Filed by CMC Materials, Inc., Aurora, IL (US)
Filed on Oct. 22, 2020, as Appl. No. 17/076,989.
Claims priority of provisional application 62/924,407, filed on Oct. 22, 2019.
Prior Publication US 2021/0115297 A1, Apr. 22, 2021
Int. Cl. C09G 1/02 (2006.01); B24B 37/04 (2012.01); C09K 3/14 (2006.01); H01L 21/321 (2006.01)
CPC C09G 1/02 (2013.01) [B24B 37/044 (2013.01); C09K 3/1409 (2013.01); C09K 3/1463 (2013.01); H01L 21/3212 (2013.01)] 8 Claims
 
1. A chemical-mechanical polishing composition comprising:
(a) an abrasive comprising ceria particles, wherein the ceria particles have an average particle size of about 60 nm to about 120 nm,
(b) about 1 ppm to about 200 ppm of a cationic homopolymer, wherein the cationic homopolymer consists essentially of quaternary amine groups as repeat units, wherein the quaternary amine groups are acyclic or incorporated into a ring structure,
(c) a quaternary ammonium salt or a quaternary phosphonium salt, and
(d) water,
wherein the polishing composition has a pH of about 5 to about 8.