INGAP/GAAS SINGLE-HETEROJUNCTION AND DOUBLE-HETEROJUNCTION BIPOLAR-TRANSISTORS GROWN BY ORGANOMETALLIC VAPOR-PHASE EPITAXY

InGaP/GaAs single-heterojunction bipolar transistors (HBTs) and double-heterojunction bipolar transistors (DHBTs) grown by organometallic vapour phase epitaxy are reported. A current gain beta = 40 was obtained for 90-mu-m diameter HBT devices at a base-collector bias of 0 V The base carbon-doping concentration for the devices was 2 x 10(19) cm-3 and the sheet resistivity (rho(s)) of the base layer was 600 OMEGA/square. For the DHBTs, a current gain beta = 27 was obtained for a base-collector bias of 2 V The carbon doping concentration in these devices was 8 x 10(18) cm-3 with rho(s) = 1400 OMEGA/square. This represents the first successful fabrication Of DHBTs for this material system.