High f/sub max/ InAlAs/InGaAs heterojunction bipolar transistors

High performance common-emitter InAlAs/InGaAs heterojunction bipolar transistors (HBTs) were fabricated with record maximum oscillation frequencies f/sub max,G/ and f/sub max,U/ of 160 and 236 GHz respectively, obtained using the -20 dB/decade extrapolation of the measured maximum stable gain (MSG) and unilateral power gain (U). The intrinsic f/sub max/ of these devices exceeds 315 GHz.<
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