Radio-Frequency-Noise Characterization and Modeling of Type-II InP–GaAsSb DHBT

This letter presents the first characterization of radio-frequency noise of type-II InP-GaAsSb double-heterojunction bipolar transistors (DHBTs) from 2 to 24 GHz. Its small-signal noise equivalent model is developed and verified with the experimental data. The noise performance of the type-II InP-GaAsSb HBT is also compared with the type-I InP-InGaAs HBT with similar cutoff frequencies larger than 300 GHz. The analysis shows that the particular type-II transistor under test has higher noise than its counterpart type-I device primarily due to the difference of dc current gain.