Polishing composition and method utilizing abrasive particles treated with an aminosilane
The inventive method comprises chemically-mechanically polishing a substrate with an inventive polishing composition comprising a liquid carrier and abrasive particles that have been treated with a compound.
1. A method of chemically-mechanically polishing a substrate, which method comprises:
(i) contacting a substrate with a chemical-mechanical polishing composition comprising:
(a) a liquid carrier, and
(b) an abrasive suspended in the liquid carrier, wherein the abrasive comprises colloidal silica particles having a surface which has been treated with a compound selected from the group consisting of an aminosilane compound, a phosphonomumsilane compound, and a sulfonium silane compound, wherein the colloidal silica particles have a percent surface coverage from about 5% to about 32%, and
(c) about 0.0001 wt.% to about 3 wt.% of a corrosion inhibitor, and
(d) an oxidizing agent,
(ii) moving the polishing composition relative to the substrate, and
(iii) abrading at least a portion of the substrate to polish the substrate, wherein the substrate comprises at least one layer of silicon oxide or at least one layer of silicon nitride, and wherein the substrate further comprises at least one metal layer, and wherein at least a portion of the substrate is removed to polish the substrate.
2. The method of claim 1 , wherein the metal layer is selected from the group consisting of tungsten, tantalum, titanium, ruthenium, copper and aluminum.
3. The method of claim 1 , wherein the polishing composition has a pH of about 1 to about 7.
4. The method of claim 1 , wherein the surface of the abrasive has been treated with an aminosilane compound that contains an ammopropyl group.
5. The method of claim 1 , wherein the oxidizing agent is selected from the group consisting of bromates, bromites, chlorates, chlorites, hydrogen peroxide, hypochlorites, iodates, hydroxylamine salts, monoperoxy sulfate, monoperoxy sulfite, monoperoxyphosphate, monoperoxyhypophosphate, monoperoxypyrophosphate, organohalo-oxy compounds, periodates, permanganate, peroxyacetic acid, and mixtures thereof.
6. The method of claim 1 , wherein the polishing composition has a pH of about 1.5 to about 5.
7. The method of claim 1 , wherein the polishing composition has a pH of about 2 to about 4.