On-Wafer Frequency- and Time-Domain Characterization of InGaAs(P)/InP Heterojunction Bipolar Transistors and FETs

A probe is designed to achieve frequency- and time-domain measurements on semiconductor devices, e.g. transistors direct on the wafer. Small signal frequency-domain information (s-parameters) were evaluated from pulse responses using Fourier transform algorithms to de-embed the device parameters from the surrounding transmission-line system and excitation pulse imperfections. A corrected time-domain response was obtained by the inverse Fourier transform of the device frequency response. Heterojunction bipolar transistors, fabricated in the InGaAsP/InP material system, were characterized with respect to their DC- and AC-properties.