US 12,454,629 B2
CMP slurries
Jimmy Granstrom, Tualatin, OR (US); and Hisashi Takeda, Tualatin, OR (US)
Assigned to FUJIMI INCORPORATED, Kiyosu (JP)
Filed by FUJIMI INCORPORATED, Kiyosu (JP)
Filed on Sep. 21, 2021, as Appl. No. 17/480,399.
Claims priority of provisional application 63/083,461, filed on Sep. 25, 2020.
Prior Publication US 2022/0098442 A1, Mar. 31, 2022
Int. Cl. H01L 21/306 (2006.01); C09G 1/02 (2006.01); C09K 3/14 (2006.01); H01L 21/304 (2006.01)
CPC C09G 1/02 (2013.01) [C09K 3/1409 (2013.01); H01L 21/304 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method for polishing a surface comprising W, TEOS/SiO2, and SiN, the method comprising:
polishing the surface comprising W, TEOS/SiO2, and SiN by applying a polishing slurry to the surface comprising W, TEOS/SiO2, and SiN, wherein the polishing slurry comprises:
an abrasive, wherein the abrasive is an anionic modified colloidal silica comprising an anionic group-containing compound chemically bonded to a surface of colloidal silica particles,
a SiN polishing rate enhancer selected from the group consisting of an amino acid and heterocycle carbon compounds, and
an anionic surfactant,
wherein an electrical conductivity value of the polishing slurry is 100 μS/cm to 350 μS/cm, and
wherein the polishing achieves a ratio of SiN removal to TEOS removal greater than about 40:1 when polishing the surface comprising W, TEOS/SiO2, and SiN using the polishing slurry.