Patent ID: 6569740
Filing Date: 2003-05-27
Classification: H01L

Abstract:
A method of forming a semiconductor device having a buffer, said method comprising:forming an insulating region in a semiconductor device substrate, wherein: said substrate includes a first portion overlying a second portion; said first and second portions have said first conductivity type; and said first portion has a lower doping concentration compared to said second portion; forming a deeper doped region in said semiconductor device substrate between a first and second control electrode, said deeper doped region having a second conductivity type that is opposite said first conductivity type, wherein said deeper doped region extends at least to said second portion; forming a gate dielectric layer over said semiconductor device substrate; forming the first control electrode of a first transistor and the second control electrode of a second transistor after forming said gate dielectric layer and forming shallow doped regions adjacent to said first and second control electrodes, wherein: said shallow doped regions have said second conductivity type; source and drain regions of said first and second transistors include said shallow doped regions; said first and second transistors share a common source/drain region; and wherein said deeper: doped region is deeper than each of said shallow doped regions.