Patent ID: 6653227
Filing Date: 2003-11-25
Classification: H01L

Abstract:
A method of fabricating a cobalt disilicide film in the manufacture of an integrated circuit comprising:providing a semiconductor substrate having silicon regions to be silicided; growing a thermal oxide layer overlying said semiconductor substrate wherein said thermal oxide layer is deliberately formed; depositing a titanium layer overlying said thermal oxide layer wherein said thermal oxide layer and said titanium layer together form a diffusion membrane overlying said silicon regions; depositing a cobalt layer overlying said titanium layer; depositing a titanium nitride capping layer overlying said cobalt layer; subjecting said substrate to a first rapid thermal anneal wherein said thermal oxide layer reacts with said titanium layer and said silicon regions to form a TixSiyOz diffusion membrane wherein said cobalt diffuses through said diffusion membrane in a controlled manner wherein composition and thickness of said diffusion membrane is known and whereby said cobalt is transformed to cobalt monosilicide where it overlies said silicon regions and wherein said cobalt not overlying said silicon regions is unreacted; removing said unreacted cobalt layer; and thereafter subjecting said substrate to a second rapid thermal anneal whereby said cobalt monosilicide is transformed to cobalt disilicide to complete formation of said cobalt disilicide film in the manufacture of said integrated circuit.