High Power InP/Ga(In)AsSb DHBTs for Millimeter-Wave PAs: 14.5 dBm Output Power and 10.4 mw/μm² Power Density at 94 GHz

Abstract

We report the 94 GHz large-signal load-pull performance of (0.3 × 9) μm 2 InP/Ga(In)AsSb double heterojunction bipolar transistors (DHBTs) in the common-emitter (CE) and common-base (CB) configurations. Both configurations were implemented side-by-side on either 20-nm-thick graded GaAsSbor GaInAsSb-base layers. A measured record saturated output power P OUT,SAT = 14.5 dBm with a corresponding power density 10.4 mW/μm 2 were achieved in the GaInAsSb-base CB configuration. The performance follows from i) the higher power gain in the CB topology and, ii) the superior BV CEO and BV CBO breakdown voltages obtained with the quaternary base which allow degradation-free operation at higher voltages. Load-pull contours show a combination of high output power and power gain in the proximity of 50 for a wide range of load impedances. In contrast, CB InP/GaAsSb DHBTs deliver P OUT,SAT = 10.6 dBm and 4.3 mW/μm 2 . For all devices considered here, CB operation improves transistor robustness against high-power device degradation. The present work provides the first report on the power performance of quaternary InP/GaInAsSb DHBTs in CE/CB topologies, with comparison to ternary InP/GaAsSb DHBTs.INDEX TERMS InP/Ga(In)AsSb, double heterojunction bipolar transistors (DHBTs), common-emitter (CE), common-base (CB), load-pull measurements, maximum output power, power gain, power density.This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination. This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination.