A new InGaP/GaAs double heterojunction bipolar transistor (DHBT) with a /spl delta/-doped wide-gap collector

Abstract

A In/sub 0.5/Ga/sub 0.5/P-GaAs double heterojunction bipolar transistor (DHBT) with a /spl delta/-doped wide-gap collector structure has been fabricated and studied. Experimental results show that this device exhibits the advantages of small offset voltage of 50 mV, a small saturation voltage of 1 V, and a large breakdown voltage of 20 V with a current gain of 20. These good characteristics are mainly due to the complete elimination of potential spike at the emitter-base (E-B) and base-collector (B-C) heterojunction. Consequently, the studied device shows a good promise for high-speed, high-power, lower-power consumption and large input signal circuit applications.