Isolated-gate InAs/AlSb HEMTs: A Monte Carlo study

In this work we present a Monte Carlo study of the influence of the presence of a native oxide which isolates the gate in InAs/AlSb high electron mobility transistors (HEMTs) on their dc and ac performance. A good agreement between simulations and experimental results of I-V curves and small signal equivalent circuit parameters has been found for low VDS, where impact ionization is not of importance. The comparison between intrinsic MC simulation results for isolated-gate and Schottky-gate HEMTs reveals a strong influence of the native oxide on the dynamic behavior of the devices, mainly on C gs , g m and f c