Temperature Influence on Tunnel Field Effect Transistors (TFETs) with Low Ambipolar Currents

摘要

This work presents a study of the temperature impact on tunnel field effect transistors performance. After design considerations regarding undesirable ambipolar currents, TFETs were simulated for temperatures ranging from 100 to 400 K. Bearing this objective in mind, the influence of each one of the most relevant transport mechanisms was analyzed and the resulting subthreshold slope was compared to the 60 mV/dec limit at room temperature for CMOS technology. At first, the device structure was defined based on the subthreshold swing extracted for different gate lengths. Sub-60mV/dec slopes were obtained by reducing ambipolar currents with an underlapped gate at the channel-drain junction. Finally, TFETs were simulated for different temperatures, individually focusing on mechanisms such as band-to-band tunneling, Shockley-Read-Hall generation and traps-assisted tunneling components. Therefore, only when all the components were joined together, it became more clear the advantages of operating devices under low temperature.