Partially depleted SOI NMOSFET's with self-aligned polysilicon gate formed on the recessed channel region

摘要

A new SOI NMOSFET with a "LOCOS-like" shape self-aligned polysilicon gate formed on the recessed channel region has been fabricated by a mix-and-match technology. For the first time, we developed a new scheme for implementing self-alignment in both source/drain and gate structure in recessed channel device fabrication. Symmetric source/drain doping profile was obtained and highly symmetric electrical characteristics were observed. Drain current measured from 0.3 /spl mu/m SOI devices with V/sub z/ of 0.773 V and T/sub ox/=7.6 nm is 360 /spl mu/A//spl mu/m at V/sub GS/=3.5 V and V/sub DS/=2.5 V. Improved breakdown characteristics were obtained and the BV/sub DSS/ (the drain voltage for 1 nA//spl mu/m of I/sub D/ at T/sub GS/=0 V) of the device with L/sub eff/=0.3 /spl mu/m under the floating body condition was as high as 3.7 V.