Raised Source/Drain MOS Transistor and Method of Forming the Transistor with an Implant Spacer and an Epitaxial Spacer

摘要

A raised source/drain MOS transistor is formed in a process that utilizes a first sidewall spacer when implanting a semiconductor region to form the heavily-doped source region and the heavily-doped drain region of the transistor, and a second different sidewall spacer when epitaxially growing the raised source region and the raised drain region of the transistor.

主权项

1. A semiconductor structure comprising:
a semiconductor region having a conductivity type; a source having a conductivity type that is opposite to the conductivity type of the semiconductor region, and including a lightly-doped source region that touches the semiconductor region, a heavily-doped source region that touches the lightly-doped source region, and a raised source region that touches the heavily-doped source region, the heavily-doped source region having a width, the raised source region having a width, the width of the raised source region being greater than the width of the heavily-doped source region; a drain having a conductivity type that is opposite to the conductivity type of the semiconductor region, and including a lightly-doped drain region that touches the semiconductor region, a heavily-doped drain region that touches the lightly-doped drain region, and a raised drain region that touches the heavily-doped drain region; a channel region of the semiconductor region lying laterally between the source and the drain; a gate dielectric touching and lying over the channel region; and a gate touching and lying over the gate dielectric.