Carbon doped GaInP/GaAs double heterostructure-emitter bipolar transistors with high current gain

Carbon-doped GaInP/GaAs double heterostructure-emitter bipolar transistors (DHEBT's) grown by MOCVD were fabricated. DC current gain of 430 (differential gain of 500) and an offset voltage of 25 mV were obtained. A gain up to 9 was achieved at a low collector current density of 10/sup -3/ A/cm/sup 2/. By using a 600 /spl Aring/ set-back layer in the collector, the saturation (knee) voltage was found to be lower than 2 V at a collector current density of 1/spl times/10/sup 4/ A/cm/sup 2/. A cutoff frequency of 23 GHz and a maximum oscillation frequency of 17.8 GHz were obtained.<
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