Patent ID: 6210489
Filing Date: 2001-04-03
Classification: H01L,Y10S

Abstract:
A method for providing a contact to a semiconductor substrate, said method comprising:providing a semiconductor substrate, said semiconductor substrate having a layer of doped silicon dioxide formed thereover, said layer of doped silicon dioxide having a topmost surface, said semiconductor substrate having a source/drain region defined therein;forming in said layer of doped silicon dioxide a space extending down through said layer of doped silicon dioxide to said source/drain region;exposing said source/drain region to a solution having an etch rate for thermal oxide of at least one-half of the etch rate of said solution for said layer of doped silicon dioxide;forming a layer of polysilicon over said semiconductor substrate and said layer of doped silicon dioxide to contact said source/drain region, said layer of polysilicon having a top; andremoving said layer of polysilicon from the top thereof downward to at least the topmost surface of said layer of doped silicon dioxide.