Electron mobilities and high-field drift velocities in strained silicon on silicon-germanium substrates

Abstract

The authors have performed a detailed analysis of the in-plane electron transport in strained Si on Si/sub 1-x/Ge/sub x/ with a Monte Carlo method. They present data on electron drift mobilities and velocities in the whole range from low to very high electric fields that can serve as a reference for the transport in modulation-doped channels. The results demonstrate significant improvements of the in-plane electron drift velocity in strained Si on Si/sub 1-x/Ge/sub x/ compared to bulk Si in the low-field and the high-field regions both at 300 and at 77 K. This advantage should contribute considerably to the high-performance potential of devices based on modulation-doped Si/SiGe heterostructures such as n-channel quantum-well MODFETs and MOSFETs.