Numerical simulation of transport properties in InAs/Si heterojunction nanowire tunneling field effect transistors

Electronic transport in InAs/Si heterojunction nanowire (NW) band-to-band tunneling field-effect transistors (TFETs) is studied numerically using the non-equilibrium Green´s function formalism based on the sp³s^*d⁵ tight-binding Hamiltonian. Our analyses have shown that TFETs based on the InAs/Si heterojunction NW have superior properties compared with those based on the Si and InAs homojunction NWs in obtaining the higher on-current, lower leakage current as well as the steeper subthreshold swing. The physical origin behind such superiority can be successfully understood by analyzing the complex band structures and the local densities of states.