Vertical GaSb/AlSb/InAs Heterojunction Tunnel-FETs: A Full Quantum Study
Résumé
We present full-quantum simulations of a vertical III-V semiconductor tunnel field-effect transistor based on a broken-gap heterojunction, where the GaSb bottom layer and the InAs top layer are separated by a large-gap AlSb interlayer. Our approach based on the nonequilibrium Green's function formalism takes into account the scattering with acoustic and optical phonons. The impact of different design options, such as the length of the gate overlap, the gate extensions, and the barrier thickness, is comprehensively investigated. We show that, under specific conditions, steep subthreshold swings smaller than 30 mV/dec can be achieved with an ON/OFF current ratio larger than 107for a supply voltage of 0.3 V.