RF characteristics of GaAs/InGaAsN/GaAs P-n-P double heterojunction bipolar transistors

We have demonstrated a P-n-P GaAs/InGaAsN/GaAs double heterojunction bipolar transistor (DHBT). The device has a low turn-on voltage (V/sub ON/) that is 0.27 V lower than in a comparable P-n-P AlGaAs/GaAs HBT. The device shows near-deal DC characteristics with a current gain (/spl beta/) greater than 45. The high-speed performance of the device are comparable to a similar P-n-P AlGaAs/GaAs HBT, with f/sub T/ and f/sub MAX/ values are both approximately 12 GHz. This device may be suitable for low-power complementary HBT circuit applications, while the aluminum-free emitter structure eliminates issues typically associated with AlGaAs.