Analysis on temperature dependent current mechanism of tunnel field-effect transistors

In this paper, the total drain current (ID) of a tunnel FET (TFET) is decomposed into each current component with different origins to analyze the ID formation mechanisms of the TFET as a function of gate voltage (VGS). Transfer characteristics are firstly extracted with fabricated Silicon channel TFETs (Si TFETs) and silicon germanium channel TFETs (SiGe TFETs) at various temperatures. The subthreshold swings (SS) of both Si TFETs and SiGe TFETs get degraded and the SSs of SiGe TFETs get degraded more as temperature becomes higher. Then, all the IDs measured at various temperatures are decomposed into each current component through technology computer aided design (TCAD) simulations with a good agreement with experimental data. As a result, it is revealed that Shockley-Read-Hall (SRH) recombination mainly contribute to the ID of a TFET before band to band tunneling (BTBT) occurs. Furthermore, the SS degradation by high temperature is explained successfully by the SRH recombination with electric field dependence.