Ultrahigh f/sub T/ and f/sub max/ new self-alignment InP/InGaAs HBT's with a highly Be-doped base layer grown by ALE/MOCVD

Abstract

We report on a new self-alignment (SA) process and microwave performance of ALE/MOCVD grown InP/InGaAs heterojunction bipolar transistors (HBT's) with a base doping concentration of 1/spl times/10/sup 2/0 cm/sup -3/. We obtained f/sub T/ of 161 GHz and f/sub max/ of 167 GHz with a 2/spl times/10 /spl mu/m emitter. These high values indicate the best performance of InP/InGaAs HBT's ever reported, in so far as we know. These values were attained by reducing the base resistance using ALE/MOCVD and base-collector capacitance using a new SA process. These results indicate the great potential of these devices for ultrahigh-speed application. >