Temperature-dependent thermal phonon relaxation time and its influence on ballistic-diffusive heat transport in SOI transistor

Abstract

A simple model of the average thermal phonon relaxation time including its temperature dependency for silicon (Si) is proposed and incorporated with the gray version of the phonon Boltzmann transport equation to investigate its effect on the temperature distribution of the Si-layer in a silicon-on-insulator (SOI) transistor with heat generation (qv). Our analysis showed that the peak temperatures both in the nonlocal heating region and at the Si/SiO2 interface increase quadratically with increasing values of qv, while in the case of the temperature-independent, however, they show a linear increase with increasing qv. The results from this work will help in understanding the phonon transport at the device-level based on Si and will provide a way how to do an efficient thermal analysis of the device-level including all the frequency and temperature dependencies of the phonon transport properties.