A Simple Proposal to Reduce Self-heating Effect in SOI MOSFETs

Abstract

In this work, we aim to design a silicon on insulator MOSFET in which the self-heating effect is fully removed. Within the proposed scheme, a T-shaped 4H-SiC region is embedded in the buried oxide layer, extended from the silicon drift region towards the substrate providing a heating pathway to improve the low thermal conductivity of the oxide. This T-shaped 4H-SiC part can absorb heat from the active region and transfer it to the substrate area. Therefore, heat dissipation rising from the high gate and drain bias in MOSFETs are reduced. Simulations show that in addition to the maximum lattice temperature that is brought from ~ 694 K to ~ 366 K, DC and AC characteristics of the device have also improved drastically. The proposed transistor demonstrates lower negative differential resistance, more carrier mobility, higher saturation current, higher DC Transconductance, less delay time, and higher cut-off frequency compared to conventional silicon on insulator MOSFET. These promising properties and competitive advantages propose the designed device as a reliable alternative for conventional MOSFETs in high power and RF applications.