DUAL ADDITIVE POLISHING COMPOSITION FOR GLASS SUBSTRATES
A chemical mechanical polishing composition comprises, consists of, or consists essentially of a liquid carrier, abrasive particles in the liquid carrier, a pyrophosphate compound, and a sulfonate compound or a compound including a quaternary ammonium group.
1 . A chemical mechanical polishing composition comprising:
a liquid carrier;
abrasive particles in the liquid carrier;
a pyrophosphate compound; and
a sulfonate compound including a sulfonate anionic surfactant or an anionic polymer including sulfonic acid groups.
2 . The composition of claim 1 , wherein the abrasive particles comprise colloidal silica particles.
3 . The composition of claim 1 , wherein the abrasive particles have a mean particle size in a range from about 15 nm to about 40 nm.
4 . The composition of claim 1 , comprising from about 5 weight percent to about 15 weight percent of the abrasive particles at point of use.
5 . The composition of claim 1 , wherein the pyrophosphate compound comprises tetrapotassium pyrophosphate (TKPP) or tetrasodium pyrophosphate (TSPP).
6 . The composition of claim 1 comprising:
from about 0.01 weight percent to about 0.2 weight percent of the pyrophosphate compound at point of use; and
from about 0.01 weight percent to about 0.2 weight percent of the sulfonate compound at point of use.
7 . The composition of claim 6 , wherein the sulfonate compound comprises a disulfonate anionic surfactant.
8 . The composition of claim 7 , wherein sulfonate compound comprises an alkyldiphenyloxide disulfonate anionic surfactant.
9 . The composition of claim 1 having a pH in a range from about 1.5 to about 3.
10 . The composition of claim 1 , further comprising an anionic polymer.
11 . The composition of claim 10 , wherein the anionic polymer is a polyacrylate or a polymethacrylate polymer.
12 . A chemical mechanical polishing composition comprising:
a liquid carrier;
abrasive particles in the liquid carrier;
a pyrophosphate compound;
a compound including a quaternary ammonium group.
13 . The composition of claim 12 comprising:
from about 0.01 weight percent to about 0.2 weight percent of the pyrophosphate compound at point of use; and
from about 0.01 weight percent to about 0.2 weight percent of the compound including the quaternary ammonium group at point of use.
14 . The composition of claim 12 , wherein the abrasive particles comprise colloidal silica particles.
15 . The composition of claim 14 , wherein the abrasive particles have a mean particle size in a range from about 15 nm to about 40 nm.
16 . The composition of claim 14 , comprising from about 5 weight percent to about 15 weight percent of the abrasive particles at point of use.
17 . The composition of claim 12 , wherein the pyrophosphate compound comprises tetrapotassium pyrophosphate (TKPP) or tetrasodium pyrophosphate (TSPP).
18 . The composition of claim 12 , wherein the compound including the quaternary ammonium group comprises a tetramethylammonium group, a tetraethylammonium group, a tetrabutylammonium group, a benzyltributylammonium group, or a mixture thereof.
19 . The composition of claim 18 , wherein compound including the quaternary ammonium group is tetraethylammonium hydroxide.
20 . The composition of claim 12 having a pH in a range from about 1.5 to about 3.
21 . A method for polishing a glass substrate, the method comprising:
(a) contacting the substrate with a polishing composition of claim 12 ;
(b) moving the polishing composition and a polishing pad relative to the substrate; and
(c) abrading the substrate to remove a portion of the substrate to polish a surface of the substrate.