Patent ID: 6063680
Filing Date: 2000-05-16
Classification: H01L

Abstract:
A method of fabricating metal oxide semiconductor field effect transistors (MOSFETs) with a recessed self-aligned silicide contact and an extended source/drain junction, said method comprising the steps of:forming a field oxide region on a silicon substrate;forming a silicon dioxide layer on said silicon substrate and said field oxide region;forming a first conductive layer on said silicon dioxide layer;forming a first oxide layer on said first conductive layer;removing portions of said silicon dioxide layer, said first conductive layer and said first oxide layer via lithography and etching processes to define a gate region;forming a pad oxide layer on said silicon substrate and a second oxide layer on a side of said first conductive layer to recover the etching damages;forming a first nitride layer on said field oxide region, said pad oxide layer and said gate region;removing portions of said first nitride layer and said pad oxide layer via lithography and etching processes to form a nitride spacer;forming a third oxide layer in said silicon substrate;removing said third oxide layer to perform a recessed surface on said silicon substrate;removing said first oxide layer;forming a first metal layer on said silicon substrate;performing a source/drain/gate implantation via ion implantation;using a silicidation process to convert portions of said first metal layer into a silicide layer, portions of said first metal layer on said field oxide layer and on a side of said nitride spacer being unreacted;removing the unreacted portions of said first metal layer;removing said nitride spacer;performing an ion implantation to form extended source and drain junctions;forming a fourth oxide layer on said silicon substrate;annealing said fourth oxide layer and said silicide layer;removing portions of said fourth oxide layer via lithography and etching processes to form a contact hole;forming a second metal layer on said fourth oxide layer and in said contact hole; andremoving portions of said second metal layer via lithography and etching processes.