Scaling the SiGe channel pmetal–oxide–semiconductor field effect transistor: The case for p+SiGe gates

Abstract

A theoretical study of the scalability of the SiGe channel pmetal–oxide–semiconductor field effect transistor to the 0.1 μm generation is presented. Devices with n+ polysilicon gates, p+ polysilicon gates, and intermediate workfunction p+ SiGe gates were considered. It was found that short channel effects became severe in the n+ gated device for channel lengths below 0.15 μm. The p+ gated device provided excellent short channel behavior, but suffered from a very poor crossover voltage. The best compromise between short channel effects and crossover voltage was obtained with the p+ SiGe gate, which gave −VCROSS close to VDD and VDIBL≈98 mV in the 0.1 μm generation.