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Tunnel Field Effect Transistors (TFETs) are known to be compromised by higher order processes that downgrade their performance compared to ballistic projections. Using a quasi-analytical model that extends the chemistry based Simmons equation to include finite temperature effects, potential variations and scattering, we exhibit that non-idealities like trap-assisted tunneling and Auger generation can explain the observed performance discrepancy. In particular, Auger generation is the dominant leakage mechanism in TFETs at low trap densities. Our studies suggest that possible ways of reducing Auger generation rate are reducing source carrier concentration and increasing the valence band transport effective mass of the source material. In this paper, we specifically investigate the impact of variations of these factors on device performance of staggered bandgap planar III-V heterojunction Tunnel FETs. 

The Tunnel field-effect-transistor (TFET) has widely been considered as one of the most viable replacements to the complementary metal oxide semiconductor (CMOS) devices due to their superior theoretical performance. Practically, though there have been scant demonstrations of the sub-60mV/dec of TFETs 1 , it has yet to be realized at acceptable current levels over a substantial current swing needed for circuit operation. It is therefore imperative to study the primary delimiters of TFETs, mainly trap-assisted tunneling (TAT) and Auger generation 2-4 , along with ways to reduce them in order to improve device performance. The effect of TAT in TFETs has been studied extensively 3,4 . Here, we study the role of transverse effective mass on Auger generation in a planar TFET and propose a method of improving device performance. 

Tunnel field-effect-transistors (TFETs) are promising candidates for next generation transistors for low power applications, as the TFETs promise low subthreshold swing (SS). Different from traditional MOSFET, the TFETs rely on energy-efficient switching of band-to-band tunneling (BTBT), therefore the SS in TFETs is not limited by the 60 mV/decade Boltzmann limit. This reduction in energy consumption makes TFETs suitable candidates to replace standard MOSFETs in low power applications. However, most experimentally demonstrated TFETs suffer from low on current[1], and the theoretical low SS is compromised by impurities and Auger generation. To understand the underlying physics and predict the device characteristics of TFETs, sophisticated numerical simulations can be used. On the other hand, physics based compact models are also required to provide fast predictions for existing and new device concepts. Furthermore, a physics based compact model is more efficient to model the effects like Auger generation which could be time-consuming for numerical calculations. In this work, we introduce a physics based compact model for homojunction TFETs with Auger generation effect considered. This compact model is based on the modified Simmons' equation at finite temperature[2]. With our compact model, the possible impact of Auger generation effect to off-current and SS is explored.