Patent ID: 6046472
Filing Date: 2000-04-04
Classification: H01L,Y10S

Abstract:
A MOSFET comprising:a gate structure on a semiconductor substrate, said gate structure including a gate dielectric oxide layer having sides and a conductive layer having sides;a first sidewall structure and a second sidewall structure abutting opposing sides of said gate structure, said first sidewall structure and said second sidewall structure each including:layer of oxide on the sides of the gate dielectric oxide layer and the sides of the conductive layer; andan insulting nitride layer extending over the layer of oxide on the sides of the gate dielectric oxide layer and the conductive layer;a drain region comprising:a lightly doped region extending into said semiconductor substrate substantially below the layer of oxide and insulating nitride layer of said first sidewall structure; anda heavily doped region extending into said semiconductor substrate abutting said lightly doped region;a source region comprising:a lightly doped region extending into said semiconductor substrate substantially below the layer of oxide and insulating nitride layer of said second sidewall structure; anda heavily doped region extending into said semiconductor substrate abutting said lightly doped region;a channel area below said gate structure and defined between said drain region lightly doped region and said source region lightly doped region;said drain region further including a first grading of dopant concentration across a junction between said channel area and said drain region lightly doped region, and a second grading of dopant concentration across a junction between said drain region heavily doped region and said drain region lightly doped region; andsaid source region further including a first grading of dopant concentration across a junction between said channel area and said source region lightly doped region, and a second grading of dopant concentration across a junction between said source region heavily doped region and said source region lightly doped region.