Patent ID: 8647985
Filing Date: 2014-02-11
Classification: B24B,C09G,H01L

Abstract:
1. A method for polishing a SiGe alloy layer on a surface of a silicon substrate, the method comprising: starting polishing by first polishing the SiGe alloy layer by at least one polishing step A, wherein the SiGe alloy layer is polished on a polishing pad containing bonded abrasive material, and wherein a polishing agent solution free of abrasive particles is introduced between the SiGe alloy layer and the polishing pad during polishing step A; and at least one polishing step B wherein the SiGe alloy layer which has been subjected to a polishing step A is polished on a polishing pad containing a bonded abrasive material, wherein a polishing agent slurry containing unbonded abrasive material is introduced between the SiGe alloy layer and the polishing pad during polishing step B, and wherein the polishing agent solution, the polishing agent slurry, or both the polishing agent solution and the polishing agent slurry comprises hydrogen peroxide or ozone as additive(s), thereby converting germanium into a water soluble compound.