부산대학교 도서관

Thermal analysis is an essential component of semiconductor device simulation for device design and thermal management. The prevalent approach of device thermal analysis uses Fourier-law-based heat diffusion equation (HDE). However, Fourier’s law is known to fail when the characteristic length is smaller than the phonon mean free path (MFP), resulting in a significant underestimation of local temperature rise. In this study, we implement non-Fourier thermal analysis on nanoscale devices using the first-principles-based nongray Boltzmann transport equation (BTE). A 3-D structure of nanoscale silicon-based FinFET is adopted as a case study. Non-Fourier effects are considered in both thermal generation and transport processes. In the thermal generation process, we use first-principles methods to investigate the selective electron–phonon energy transfer process and obtain the mode-level phonon generation rates. In the thermal transport process, we solve the nongray phonon BTE to determine the temperature distribution of the devices, in which the material-dependent phonon properties are calculated by first-principles methods. Through comparisons with HDE and previous models, we demonstrate the considerable impact of non-Fourier effects on temperature rise and electrical performance, highlighting the significance of incorporating non-Fourier thermal analysis into nanoscale device simulations. Our method also shows good agreement with experimental temperature measurements, which can be readily extended to a variety of devices and operating conditions.