Analysis of InP/InGaAs double heterostructure bipolar transistors for high frequency applications

The results of a two-dimensional simulation of an InP/InGaAs double heterostructure bipolar transistor are discussed. High-frequency performance is evaluated from transient solutions to the governing equations. The computed f/sub max/ is found to be larger than twice f/sub I/ over a wide range of collector current; values of f/sub max/ as high as 190 GHz have been computed for unoptimized structures. Proper doping and compositional grading in the base and collector layers are shown to reduce the problem of the conduction band spike at high collector current densities.<
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