Chemical mechanical polishing slurry and method for using same

An aqueous chemical mechanical polishing slurry comprising:

• from about 0.5 to about 15 weight percent fumed silica;
• from about 50 ppm to about 2.0 weight percent of at least one tertiary alcoholamine;
• and
• from about 0.01 to about 1.0 weight percent of a buffering agent selected from a carbonate, a bicarbonate, or mixtures thereof, wherein the slurry has a pH of from about 9.0 to about 10.5.

A method for chemical-mechanical polishing of a substrate containing an first insulator layer and at least one second layer selected from at least one conductive or semi-conductive material the method comprising the steps of:

• a) providing an aqueous chemical mechanical polishing slurry comprising an abrasive and a tertiary amine;
• b) applying the slurry to the substrate;
• and
• c) removing at least a portion of the second layer by bringing a polishing pad into contact with the substrate and moving the pad in relation to the substrate.

A method for chemical-mechanical polishing of a substrate containing an insulator layer and a polysilicon layer, the method comprising the steps of:

• a) providing an aqueous chemical mechanical polishing slurry comprising from about 0.5 to about 15 weight percent fumed silica, from about 50 ppm to about 2.0 weight percent 2-dimethylamino-2-methyl-1-propanol, and at least one buffering agent wherein the slurry has a pH of from about 9.0 to about 10.5;
• b) applying the slurry to the substrate;
• and
• c) removing at least a portion of the polysilicon layer by bringing a polishing pad into contact with the substrate and moving the pad in relation to the substrate.