Effect of temperature on analog performance of Mg2Si source heterojunction double gate tunnel field effect transistor

Abstract

Tunnel field effect transistor (TFET) has been recognized as a better candidate to replace Metal Oxide Semiconductor Field Effect Transistor (MOSFET) owing to its competence to achieve subthreshold swing (SS) less than 60 mV/decade and to reduce short channel effects (SCEs). However, certain limitations (low ON current and ambipolar conduction) need to be overcome so as to enhance the performance of TFET. In this paper, source material engineering (SME) is investigated to enhance ION, by replacing the material of the source region of conventional silicon double gate (DG) TFET by a low bandgap material Magnesium Silicide (Mg2Si). It is observed from simulation results that with Mg2Si as a source presented superior performance with reference to ION, Vth, SS, and ION/IOFF ratio as compared to the conventional Si DG-TFET. Further, reliability issues related to the temperature affectability for the electrical/analog performance of the proposed device is investigated for ambient temperature range (200 K to 400 K). The study done for temperature affectability reveals that, Shockley–Read–Hall recombination dominates in the subthreshold region and band to band tunneling (BTBT) mechanism is dominant in superthreshold region. Furthermore, as temperature is elevated from 200 K to 400 K, IOFF shows significant degradation by an order of 106. Also, it is evident that with increase in temperature threshold voltage (Vth) decreases and transconductance (gm) increases. This study will be helpful in achieving the better performance for Mg2Si source DG-TFET implemented in analog applications.