Mason's Gain of Down-Scaled InP HBTs with Two Setups: Effects of Probes and Frequency Extenders
A. Kanitkar1, R. Doerner1, T.K. Johansen2, W. Heinrich1, and T. Flisgen1,3
Published in:
17th German Microwave Conference (GeMiC 2026), Karlsruhe, Germany, Mar 9-11, ISBN 979-8-3195-1955-9, pp. 141-144, doi:10.1109/GeMiC71240.2026.11516367 (2026).
Abstract:
In this work, indium phosphide heterojunction bipolar transistors with emitter widths of 0.9 µm, 0.7 µm, 0.5 µm, and 0.3 µm are measured with two setups. The measurement setups differ in the utilization of commercially available RF probes and in presence of frequency extenders. The multiline Thru-Reflect-Line calibrated S-parameters of transistors measured with the two setups show disagreements, revealing the presence of on-wafer parasitic effects. Although the S-parameter deviations are comparatively small, they translate into larger artifacts in Mason's gain determination. This raises questions on the reliability of the extracted fmax values. Plotting the square root of Mason's gain U multiplied by its corresponding frequency f , ⎷U ×f, a common representation of fmax, highlights the necessity of implementing a more robust calibration technique to take these unwanted effects into account for well-founded fmax extraction.
1 Ferdinand-Braun-Institut (FBH), Germany
2 Technical University of Denmark, Denmark
3 Brandenburg University of Technology (BTU), Germany
Keywords:
InP HBTs, mTRL calibration, on-wafer measurements, transistor characterization
© Copyright 2026 IEEE - All rights reserved and © IMA e.V. Ratingen, Germany. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE and IMA e.V.
Rightslink® by Copyright Clearance Center
Full version in pdf-format.