Two-dimensional simulation of type-Ⅱ InP/GaAsSb/InP double heterojunction bipolar transistors

摘要

Two-dimensional (2D) numerical simulations of self-aligned sub-micron InP/GaAsSb double heterojunc-tion bipolar transistors (DHBTs) were performed to investigate the effects of base band gap narrowing and surface recombination. Base energy band gaps of 0.72 eV and 0.67 eV for GaAs_(0.51)Sb_(0.49) bases with doping levels of 5 x 10~(18) and 5 x 10~(19) cm~(-3) were extracted from the comparison between the measurement data and simulation results. We took into account the surface Fermi level pinning and introduced a surface state model for the emitter side wall and extrinsic base surface. To the best of our knowledge, a good match between measured and simulated InP/GaAsSb DHBTs characteristics, from low to high current densities has not been achieved prior to the present work.