Patent ID: 6200840
Filing Date: 2001-03-13
Classification: H01L

Abstract:
A method for preventing boron segregation and out diffusion for producing PMOS devices, said method comprising:providing a semiconductor substrate having a first conductivity type;forming a gate oxide layer on said semiconductor substrate;forming a gate layer on said gate oxide layer;firstly implanting said semiconductor substrate using said gate layer as a mask to form at least two high doped drain regions (HDDs) having a second conductivity type opposite to said first conductivity type;forming a first dielectric layer on top of the exposed surface of said gate layer and on said semiconductor substrate, said first dielectric layer for preventing boron segregation and out diffusion, wherein material of said first dielectric layer is a compound of nitrogen and oxygen;forming a second dielectric layer on said first dielectric layer;forming a third dielectric layer on said second dielectric layer;forming a dielectric spacer on sidewall of said gate layer and said gate oxide layer, thereby anisotropically etching portions of said third and said second dielectric layer;secondly implanting said semiconductor substrate to form source/drain regions having the second conductivity type opposite to the first conductivity type by using said gate region and said spacer region as a mask;annealing the resulting structure; andforming silicide on said source/drain regions and said gate region.