Heterojunction bipolar transistor with an additional minority carrier reflection barrier in the emitter

Abstract

A heterojunction bipolar transistor (HBT) structure that provides an additional minority carrier reflection/confinement barrier within the quasi-neutral emitter region has been proposed and investigated by means of numerical simulations. The proposed device structure has been demonstrated to perform better than conventional HBTs - a higher current gain with better uniformity, which has been achieved without affecting the high frequency performance. In addition, the current gain was found to be relatively insensitive to temperature changes in the range of 250 K to 450 K, thus making the new device structure more suitable for high power applications.