Single and double heterojunction bipolar transistors in collector-up topology

For the first time, DC- and RF characteristics of single and double heterojunction bipolar transistors (S-HBT and D-HBT respectively) in collector-up topology are measured and compared. Both devices are realized in InGaP/GaAs technology and offer high common emitter breakdown voltage (BVceo > 16V) and high maximum oscillation frequency (fmax > 115GHz)