Large Variation in Temperature Dependence of Band-to-Band Tunneling Current in Tunnel Devices

Abstract

The observation of a significant temperature-dependent variation in the <inline-formula> <tex-math notation= LaTeX >${I}$ </tex-math></inline-formula>–<inline-formula> <tex-math notation= LaTeX >${V}$ </tex-math></inline-formula> characteristics of tunneling devices is often interpreted as a signature of a trap-assisted-tunneling dominated current. In this letter, we use a ballistic 2D quantum-mechanical simulator, calibrated using the measured temperature-dependent <inline-formula> <tex-math notation= LaTeX >${I}$ </tex-math></inline-formula>–<inline-formula> <tex-math notation= LaTeX >${V}$ </tex-math></inline-formula> characteristics of Esaki diodes, to demonstrate that the temperature dependence of band-to-band tunneling (BTBT) current can vary significantly in both Esaki diodes and tunnel FETs. The variation of BTBT current with temperature is impacted by doping concentration, gate voltage, possible presence of a highly-doped pocket at the tunnel junction, and material.