STRAINED SILICON MOS DEVICE WITH BOX LAYER BETWEEN THE SOURCE AND DRAIN REGIONS

摘要

A MOS device comprises a gate stack comprising a gate electrode disposed on a gate dielectric, a first spacer and a second spacer formed on laterally opposite sides of the gate stack, a source region proximate to the first spacer, a drain region proximate to the second spacer, and a channel region subjacent to the gate stack and disposed between the source region and the drain region. The MOS device of the invention further includes a buried oxide (BOX) region subjacent to the channel region and disposed between the source region and the drain region. The BOX region enables deeper source and drain regions to be formed to reduce transistor resistance and suicide spike defects while preventing gate edge junction parasitic capacitance.