微尺度SOI FinFET自热效应分析OA

Since the thermal conductivity of silicon dioxide is much lower than that of the top silicon film,the buried oxide(BOX)layer with low thermal conductivity isolates the channel from the substrate,exacerbating the self-heating effect(SHE)in silicon-on-insulator(SOI)devices,which severely impacts key parameters such as carrier mobility,transconductance,and threshold voltage.This paper investigates the self-heating effect in SOI FinFET and its influencing factors.By considering the effects of bound electrons,free electrons,doping concentration,and impurity scattering relaxation time on phonon scattering,an improved TCAD(Technology Computer Aided Design)numerical simulation model for device thermal conductivity is established.Numerical simulation results show that the BOX layer hinders heat dissipation to the substrate,leading to localized temperature rise in the device,and that increasing BOX thickness aggravates the self-heating effect.As the fin size increases,the peak channel temperature difference also gradually rises.Extending the source/drain extension regions widens the heat dissipation path,thus reducing the peak device temperature while shifting the hotspot toward the drain.A higher ambient temperature elevates the channel temperature,causing a sharp increase in the subthreshold swing(SS),thereby degrading device performance.Thermal boundary conditions significantly affect the peak channel temperature and its distribution,with the drain contact thermal resistance having the most pronounced impact.Findings provide important insights for analyzing the self-heating effect in nanoscale SOI FinFET devices.