Investigation of self-heating effect in SOI tunnel field-effect transistor

The built-in tunnel barrier in Tunneling Field Effect Transistors results in a low ON current. As an excellent dielectric isolation technology, silicon-on-insulator (SOI) technology makes TFET exhibit a higher ON current ratio. However, due to the low thermal conductivity of the buried SiO₂ layer, heat dissipation and self-heating effect become serious issues of most SOI devices. In this paper, self-heating effect in SOI-TFET is investigated by using the SILVACO TCAD tools. The influences caused by structural characteristics on the self-heating effect are discussed. Furthermore, the impact of environmental temperature on the performance of the SOI-TFET device is also discussed with a wide range from 300 K to 500 K. Simulation results demonstrate that SOI-TFET has weak self-heating effect due to the Band-to-Band tunneling (BTBT) operating mechanism. Besides, the drive current of SOI-TFET exhibits a positive variation with increasing temperature which is contrary to the SOI-MOSFET.