SELF-STOPPING POLISHING COMPOSITION AND METHOD
A chemical mechanical polishing composition for polishing a substrate having a silicon oxygen material comprises, consists of, or consists essentially of a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, a self-stopping agent, and a cationic polymer.
1 . A chemical mechanical polishing composition comprising:
a liquid carrier;
cubiform ceria abrasive particles dispersed in the liquid carrier;
a self-stopping agent; and
a cationic polymer.
2 . The composition of claim 1 , wherein the cubiform ceria abrasive particles comprise a mixture of cerium oxide and lanthanum oxide.
3 . The composition of claim 1 , wherein the cubiform ceria abrasive particles have a molar ratio of lanthanum to lanthanum plus cerium in a range from about 1 to about 15 percent.
4 . The composition of claim 1 , wherein the cubiform ceria abrasive particles have a BET surface area in a range from about 3 m 2 /g to about 14 m 2 /g.
5 . The composition of claim 1 , wherein the cubiform ceria abrasive particles have an average particle size in a range from about 50 to about 500 nm.
6 . The composition of claim 1 , comprising from about 0.01 weight percent to about 1 weight percent of the cubiform ceria abrasive particles.
7 . The composition of claim 1 , wherein the self-stopping agent is a ligand that is attached to the cubiform ceria abrasive particles.
8 . The composition of claim 1 , wherein the self-stopping agent is kojic acid, maltol, ethyl maltol, propyl maltol, hydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, benzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, caffeic acid, sorbic acid, potassium sorbate, and combinations thereof.
9 . The composition of claim 8 , wherein the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, kojic acid, potassium sorbate, or a combination thereof.
10 . The composition of claim 1 , wherein the cationic polymer is selected from the group consisting of poly(vinylimidazolium), poly(vinylimidazole),), poly(vinylimidazole), methacryloyloxyethyltrimethylammonium, poly(diallyldimethylammonium), Polyquatermium-2, Polyquatemium-11, Polyquatemium-16, Polyquaternium-46, Polyquaternium-44, polylysine, and combinations thereof.
11 . The composition of claim 10 , wherein the cationic polymer is poly(vinylimidazolium),), poly(vinylimidazole), methacryloyloxyethyltrimethylammonium, polylysine, or a combination thereof.
12 . The composition of claim 1 , wherein
a point of use concentration of the cubiform ceria abrasive particles is from about 0.01 weight percent to about 1 weight percent;
a point of use concentration of the self-stopping agent is from about 200 ppm by weight to about 5000 ppm by weight; and
a point of use concentration of the cationic polymer is from about 5 ppm by weight to about 500 ppm by weight.
13 . The composition of claim 1 , further comprising a carboxylic acid rate enhancer.
14 . The composition of claim 13 , wherein the carboxylic acid rate enhancer is picolinic acid, acetic acid, 4-hydroxybenzoic acid, or a mixture thereof.
15 . The composition of claim 1 , further comprising an unsaturated carboxylic monoacid rate inhibitor selected from the group consisting of acrylic acid, crotonic acid, 2-pentenoic acid, trans-2-hexenoic acid, trans-3-hexenoic acid, 2-hexynoic acid, 2,4-hexadienoic acid, potassium sorbate, trans-2-methyl-2-butenoic acid, 3,3-dimethylacrylic acid, and combinations thereof.
16 . The composition of claim 15 , wherein the unsaturated carboxylic monoacid rate inhibitor is crotonic acid.
17 . The composition of claim 1 , further comprising a non-polymeric cationic compound selected from the group consisting of 2-(dimethylamino)ethyl acrylate, 2-(dimethylamino)ethyl methacrylate, 3-(dimethylamino)propyl methacrylamide, 3-(dimethylamino)propyl acrylamide, lysine, 3-methacrylamidopropyl-trimethyl-ammonium, 3-acrylamidopropyl-trimethyl-ammonium, diallyldimethylammonium, 2-(acryloyloxy)-N,N,N-trimethylethanaminium, methacryloyloxyethyltrimethylammonium, N,N-dimethylaminoethyl acrylate benzyl, N,N-dimethylaminoethyl methacrylate benzyl, and combinations thereof.
18 . The composition of claim 17 , wherein the non-polymeric cationic compound comprises diallyldimethylammonium, methacryloyloxyethyltrimethylammonium, lysine, 2-(dimethylamino)ethyl methacrylate, or a mixture thereof.
19 . The composition of claim 17 , wherein the cationic polymer comprises polylysine and the non-polymeric compound comprises diallyldimethylammonium.
20 . The composition of claim 1 , further comprising triethanolamine.
21 . The composition of claim 1 , further comprising benzotriazole or bis tris methane.
22 . The composition of claim 1 , having a pH in a range from about 5 to about 10.
23 . The composition of claim 1 , wherein:
the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, kojic acid, potassium sorbate, or a combination thereof;
the cationic polymer is poly(vinylimidazolium), poly(methacryloyloxyethyl trimethylammonium), polylysine, poly(diallyldimethylammonium), or a combination thereof; and
the composition further comprises picolinic acid, acetic acid, 4-hydroxybenzoic acid, or a mixture thereof.
24 . The composition of claim 23 , further comprising triethanolamine and benzotriazole.
25 . The composition of claim 23 , wherein the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, or a combination thereof and the pH is in a range from about 7 to about 9 at point of use.
26 . The composition of claim 25 , comprising at least 250 ppm by weight of the self-stopping agent at point of use and 50 ppm by weight of the cationic polymer at point of use.
27 . The composition of claim 23 , wherein the self-stopping agent is kojic acid, potassium sorbate, or a combination thereof and the pH is in a range from about 5 to about 6.5 at point of use.
28 . The composition of claim 1 , wherein:
the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, or a combination thereof; and
the cationic polymer is ε-poly-L-lysine, poly(vinylimidazolium), or a combination thereof.
29 . The composition of claim 28 , further comprising crotonic acid.
30 . The composition of claim 28 , further comprising a non-polymeric cationic compound selected from the group consisting of diallyldimethylammonium, methacryloyloxyethyltrimethylammonium, lysine, 2-(dimethylamino)ethyl methacrylate, or a mixture thereof.
31 . The composition of claim 30 , comprising:
at least 250 ppm by weight of the self-stopping agent;
at least 20 ppm by weight of the cationic polymer; and
at least 20 ppm by weight of the non-polymeric cationic compound.
32 . A method of chemical mechanical polishing a substrate including a silicon oxide dielectric material, the method comprising:
(a) providing a polishing composition including a liquid carrier, cubiform ceria abrasive particles dispersed in the liquid carrier, a self-stopping agent, and a cationic polymer;
(b) contacting the substrate with said provided polishing composition;
(c) moving said polishing composition relative to the substrate; and
(d) abrading the substrate to remove a portion of the silicon oxide dielectric material from the substrate and thereby polish the substrate.
33 . The method of claim 32 , wherein an active removal of the silicon oxide dielectric material in a patterned region of the substrate to a trench loss removal of the silicon oxide dielectric material is greater than about 5 in (d).
34 . The method of claim 32 , wherein:
the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, kojic acid, potassium sorbate, or a combination thereof;
the cationic polymer is poly(vinylimidazolium), poly(methacryloyloxyethyl trimethylammonium), polylysine, poly(diallyldimethylammonium), or a combination thereof; and
the polishing composition further comprises picolinic acid, acetic acid, 4-hydroxybenzoic acid, or a mixture thereof.
35 . The method of claim 32 , wherein:
the self-stopping agent is benzhydroxamic acid, salicylhydroxamic acid, or a combination thereof;
the cationic polymer is ε-poly-L-lysine, poly(vinylimidazolium), or a combination thereof.
36 . The method of claim 35 , wherein the polishing composition further comprises a non-polymeric cationic compound selected from the group consisting of diallyldimethylammonium, methacryloyloxyethyltrimethylammonium, lysine, 2-(dimethylamino)ethyl methacrylate, or a mixture thereof.