Patent ID: 8735293
Filing Date: 2014-05-27
Classification: C09G,H01L

Abstract:
1. A method for chemical mechanical polishing of a substrate, comprising: providing a substrate, wherein the substrate comprises a germanium-antimony-tellurium phase change alloy; providing a chemical mechanical polishing composition, wherein the chemical mechanical polishing composition consists essentially of water; 1 to 5 wt % colloidal silica abrasive particles having an average particle size of 1 to 50 nm; 0.01 to 5 wt % quaternary ammonium compound; and, optionally, an acid or base for adjusting pH; wherein the quaternary compound is tetrabutyl ammonium hydroxide; wherein the acid is selected from nitric acid, sulfuric acid and hydrochloric acid; wherein the base is selected from ammonium hydroxide and potassium hydroxide; wherein the chemical mechanical polishing composition is oxidizer free and chelating agent free; wherein the chemical mechanical polishing composition has a pH 7 to 12; providing a chemical mechanical polishing pad; creating dynamic contact at an interface between the chemical mechanical polishing pad and the substrate; and dispensing the chemical mechanical polishing composition onto the chemical mechanical polishing pad at or near the interface between the chemical mechanical polishing pad and the substrate; wherein at least some of the germanium-antimony-tellurium phase change alloy is removed from the substrate; wherein the substrate further comprises tetraethyl orthosilicate (TEOS); and, wherein the chemical mechanical polishing composition exhibits a germanium-antimony-tellurium phase change alloy to TEOS removal rate selectivity of >60:1.