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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. 

Abstract Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise. In this article, we investigate the band structure‐related mechanisms that influence impact ionization. Band‐structures calculated using an empirical tight‐binding method and Monte Carlo simulations reveal that the mini‐gaps in the conduction band do not inhibit electron impact ionization. Good agreement between the full band Monte Carlo simulations and measured noise characteristics is demonstrated. image 

Superior performance of digital alloy APDs is attributed to the formation of "minigaps" in the material band-structure. However, no improvement is observed in dilute nitride APDs in presence of minigaps. We propose criteria which can judge the effectiveness of these minigaps. 

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.