Proposal and Simulation of Si-Ge Heteroj unction Base Hybrid Mode Transistor

A new kind of dev ice, Si-Ge heterojunction base hybrid mo de transistor, based on the conventional hybrid mode transistor, is proposed. Si nce its base region adopts Si-Ge alloy w hose forbidd en band is more narrow, the barrier of t he hole injecting from base region to em itter region increases and the hole curr ent decreases so that the injecting effi ciency increases. On the other hand, sin ce the electron mobility increases the c ut-off frequency increases. Thus, the de vice has high β, low resistance and shor t transit time in base region. The devic e simulation testifies the featuring of high output, high gain in low temperatur e, relative high gain in normal temperat ure and high cut-off frequency, which re presents the devices in ICs of the next generation.