Treatment of semiconductor wafers

Abstract

A semiconductor wafer having a surface layer of semiconductor material that exhibits a reduced number of defects. This feature is achieved by a treatment method wherein the surface layer undergoes a chemical-mechanical polishing step, an intermediate step of cleaning the surface of the surface layer of semiconductor material using an SC1 solution, and then an RCA cleaning step.

1 . A wafer having at least a surface layer of a semiconductor material, with the surface layer having a thickness of less than 1000 Å, a roughness of less than 2.5 Å rms for a scan area of 2 μm×2 μm, and a HF defect density of less than 0.5/cm 2 .  
     
     
         2 . The wafer of  claim 1 , which has a HF defect density of less than 0.1/cm 2 .  
     
     
         3 . The wafer of  claim 1 , wherein the surface layer of semiconductor material is made of silicon or silicon germanium and the wafer is a silicon on insulator structure or a silicon-germanium on insulator structure.  
     
     
         4 . The wafer of  claim 3 , wherein the surface layer of semiconductor material is made of silicon.  
     
     
         5 . The wafer of  claim 3 , wherein the surface layer of semiconductor material is made of silicon germanium.  
     
     
         6 . The wafer of  claim 3 , wherein the wafer is a silicon on insulator structure.  
     
     
         7 . The wafer of  claim 3 , wherein the wafer is a silicon-germanium on insulator structure.