Impact of Temperature and Trap Charges on Heterojunction Tunnel FET

Abstract

In this article, a comprehensive comparison of Si-SiGe hetero-junction tunnel field effect transistor (TFET) and conventional TFET is presented. The Silicon-Germanium (SiGe) pocket utilized in the proposed TFET structure reduces the tunneling distance to provide enhanced ON current as compared to the conventional one. Moreover, the proposed heterojunction TFET offers super-steeper sub-threshold swing (SS) of 14 mV/dec. The temperature dependence characteristics and its impact on interface traps for both the structures are explored and examined. Results expose that TFET shows less temperature dependence in the ON state due to band to band tunneling mechanism of current conduction. While, in the OFF state the temperature dependency is increased. It is found that the TFET has less effect of interface traps on ON current degradation than leakage current. It is also found that the proposed hetero-junction TFET shows better immunity against trap effect even under temperature variation as compared to the conventional TFET. This confirms the superiority and reliability of the proposed hetero-junction TFET for recent semiconductor industries.