An Improved Model of Self-Heating Effects for Ultrathin Body SOI nMOSFETs Based on Phonon Scattering Analysis

Self-heating effects of ultrathin body silicon-on-insulator (SOI) structure are studied by introducing the phonon scattering mechanisms. An improved model of self-heating effects is present considering the heat generation and the thermal diffusion mechanisms. The thermal conductivity parameters are extracted using transient plane source method from the experiment data. The temperature distributions caused by self-heating effects in the silicon layer of SOI nMOSFETs are verified by the numerical Sentaurus TCAD simulation data. The results show that with the thickness of the silicon layer between the gate and the buried oxide decreasing down to sub-20 nm, the phonon scattering rate of free and bound electrons, and the boundary reflection should be taken into consideration in the modeling of self-heating effects.