Half-micron CMOS on ultra-thin silicon on insulator

A 0.5- mu m CMOS technology on ultrathin SIMOX SOI (silicon-on-insulator) material with silicon film thickness of 80 nm is studied. When compared with bulk devices the SOI NMOS devices showed a slightly reduced current-drive-capability, a small negative differential output conductance at high gate bias, and a strongly reduced breakdown voltage. Floating-substrate effects remain significant even for SOI devices on ultrathin material. The hot-carrier degradation of the SOI NMOS devices was significantly enhanced by electron injection in the buried oxide layer. The performance of ring oscillators on SOI material was excellent. Furthermore, fully functional 2K SRAM circuits were fabricated. The main advantages of ultrathin-film SOI seem to be the improved circuit properties and the simplified fabrication technology. The reduction of the floating-body effects in the devices on ultrathin-film SOI is required to make SOI a competitor to bulk material for future deep submicron CMOS.<
>