Quantization effects on the phonon-limited electron mobility in ultrathin SOI, sSOI and GeOI devices

Abstract

The phonon-limited electron mobility in inversion layers is studied in fully depleted silicon-on-insulator (FD-SOI) MOSFET as a function of transverse effective field and semiconductor film thickness. A quantum-mechanical procedure based on the solution of 1D-coupled Poisson/Schrödinger equations is employed to calculate the phonon–electron mobility using a relaxation time approximation. The influence of quantization effects on the phonon-limited electron mobility in ultrathin SOI, strained-SOI and GeOI MOSFET is investigated. A comparative study of mobility shows an enhancement factor varying from 1.5 to 2.5 for film thicknesses ranging from 5 nm to 20 nm using both strained-silicon and germanium materials.