Polishing compositions and methods of use thereof
A polishing composition includes an anionic abrasive; a pH adjuster; a transition metal catalyst; and an amino acid. A method of polishing a substrate includes the steps of: applying the polishing composition described herein to a surface of a substrate, wherein the surface comprises tungsten or molybdenum; and bringing a pad into contact with the surface of the substrate and moving the pad in relation to the substrate.
1 . A polishing composition, comprising:
an anionic silica abrasive, wherein the anionic abrasive comprises terminal groups of formula (I):
—O m —Si—(CH 2 ) n —CH 3 (I),
in which m is an integer from 1 to 3; n is an integer from 0 to 10; the —(CH 2 ) n —CH 3 group is substituted by at least one carboxylic acid group;
a pH adjuster;
a transition metal catalyst; and
an amino acid;
wherein the polishing composition has a pH of about 1 to about 7, and
wherein the polishing composition is free of anionic polymers and anionic surfactants.
2 . The composition of claim 1 , wherein the anionic silica abrasive is in an amount of from about 0.01 wt % to about 50 wt % of the composition.
3 . The composition of claim 1 , wherein the pH adjuster is selected from the group consisting of formic acid, acetic acid, malonic acid, citric acid, propionic acid, malic acid, adipic acid, succinic acid, lactic acid, oxalic acid, peracetic acid, potassium acetate, phenoxyacetic acid, benzoic acid, nitric acid, sulfuric acid, sulfurous acid, phosphoric acid, phosphonic acid, hydrochloric acid, periodic acid, lithium hydroxide, potassium hydroxide, sodium hydroxide, cesium hydroxide, ammonium hydroxide, triethanolamine, diethanolamine, monoethanolamine, methylethanolamine, methyldiethanolamine, tetrabutylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, ethyltrimethylammonium hydroxide, diethyldimethylammonium hydroxide, dimethyldipropylammonium hydroxide, benzyltrimethylammonium hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, choline hydroxide, and mixtures thereof.
4 . The composition of claim 1 , wherein the pH adjuster is in an amount of from about 0.0001 wt % to about 30 wt % of the composition.
5 . The composition of claim 1 , wherein the transition metal catalyst comprises iron(III) sulfate, iron(III) nitrate, iron(III) chloride, iron(III) oxalate, potassium tris(oxalato)ferrate(III), ammonium hexacyanoferrate(III), potassium hexacyanoferrate(III), iron(III) citrate, ammonium iron(III) citrate, ammonium iron(III) oxalate trihydrate, iron(III) nitrate or a hydrate thereof, iron(III) citrate tribasic monohydrate, iron(III) acetylacetonate, or ethylenediaminetetraacetic acid iron(III) sodium salt hydrate.
6 . The composition of claim 1 , wherein the transition metal catalyst is in an amount of from about 0.0001 wt % to about 1 wt % of the composition.
7 . The composition of claim 1 , wherein the amino acid comprises amino acetic acid, glycine, bicine, tricine, alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, glutamic acid, arginine, lysine, or tyrosine.
8 . The composition of claim 1 , wherein the amino acid is in an amount of from about 0.001 wt % to about 10 wt % of the composition.
9 . The polishing composition of claim 1 , further comprising:
a chelating agent selected from the group consisting of ethylenediaminetetracetic acid, iminodiacetic acid, N-hydroxyethyl-ethylenediaminetriacetic acid, nitrilotriacetic acid, diethylenetriaminepentacetic acid, hydroxyethylethylenediaminetriacetic acid, triethylenetetraaminehexaacetic acid, diaminocycloheanetetraacetic acid, nitrilotrimethylphosphonic acid, ethylenediaminetetra(methylenephosphonic acid), 1-hydroxyl ethylidene-1,1-diphosphonic acid, diethylenetriamine penta (methylene phosphonic acid), hydroxyethylidene diphosphonic acid, 2-phosphono-1,2,4-butane tricarboxylic acid, aminotrimethylene phosphonic acid, hexamethylenediamine tetra(methylenephosphonic acid), bis(hexamethylene)triamine phosphonic acid, amino acetic acid, and combinations thereof.
10 . The polishing composition of claim 9 , wherein the chelating agent is in an amount of from about 0.001% to about 1% by weight of the composition.
11 . The polishing composition of claim 1 , further comprising an oxidizing agent selected from the group consisting of hydrogen peroxide, orthoperiodic acid, metaperiodic acid, dimesoperiodic acid, diorthoperiodic acid, ammonium periodate, potassium periodate, sodium periodate, ammonium persulfate, iodic acid, iodate salts, perchloric acid, perchloroate salts, hydroxylamine and hydroxylamine salts, and mixtures thereof.
12 . The polishing composition of claim 11 , wherein the oxidizing agent is in an amount of from about 0.001% to about 5% by weight of the composition.
13 . The polishing composition of claim 1 , further comprising an azole-containing corrosion inhibitor selected from the group consisting of triazole, tetrazole, benzotriazole, tolyltriazole, 1,2,4-triazole, ethyl benzotriazole, propyl benzotriazole, butyl benzotriazole, pentyl benzotriazole, hexyl benzotriazole, dimethyl benzotriazole, chloro benzotriazole, dichloro benzotriazole, chloromethyl benzotriazole, chloroethyl benzotriazole, phenyl benzotriazole, benzyl benzotriazole, aminotriazole, aminobenzimidazole, pyrazole, imidazole, aminotetrazole, and mixtures thereof.
14 . The polishing composition of claim 13 , wherein the azole-containing corrosion inhibitor is in an amount of from about 0.0001% to about 1% by weight of the composition.
15 . The composition of claim 1 , further comprising water.
16 . The composition of claim 15 , wherein the water is in an amount of from about 20 wt % to about 99 wt % of the composition.
17 . A method, comprising:
applying the polishing composition of claim 1 to a surface of a substrate, wherein the surface comprises tungsten or molybdenum; and
bringing a pad into contact with the substrate and moving the pad in relation to the substrate.
18 . The method of claim 17 , further comprising producing a semiconductor device from the substrate treated by the polishing composition.