DC characteristics of MOVPE-grown Npn InGaP/InGaAsN DHBTs

The authors have demonstrated, for the first time, a functional Npn double heterojunction bipolar transistor using a novel material, InGaAsN, with a bandgap energy of 1.2 eV as the p-type base layer. A 300 /spl Aring/ thick In/sub x/Ga/sub 1-x/As graded layer was introduced to reduce the conduction band offset at the p-type InGaAsN base and n-type GaAs collector junction. For an emitter size of 500 /spl mu/m/sup 2/, a peak current gain of 5.3 has been achieved.