An Improved EM-Simulation Procedure to Extract Extrinsic Elements of Terahertz InP DHBTs

P. Sriperumbuduri1,2, T.K. Johansen2,3, K. Erkelenz2, A. Wentzel2, R. Doerner2, S. Boppel2, and M. Rudolph1,2

Published in:

13th German Microwave Conference (GeMiC 2020), Cottbus, Germany, Mar. 09-11, ISBN 978-3-9820397-1-8, pp. 240-243 (2020).

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For accurate small-signal modeling of double heterojunction bipolar transistors (DHBT), electromagnetic (EM) simulations of the outer shell of the DHBT are used for de-embedding the external parasitic parameters. However, under different simulation setup conditions, the parasitic elements can be overestimated or underestimated. This paper presents a systematic approach to set up an EM simulation and obtain accurate parasitic elements of DHBT devices using Ansys high-frequency structure simulator (HFSS). An innovative simulation method is also introduced in order to calculate parasitic base capacitance (Cpb) and base-collector capacitance (Cpbc), which cannot be extracted accurately from "off-state" measurements. Finally, the EM simulation de-embedded small-signal model is found to provide a good fit to the measured data from 50 MHz to 150 GHz.

1 FG Hochfrequenz- und Mikrowellentechnik Ulrich-L.-Rohde Stiftungsprofessur, Brandenburgische Technische Universität Cottbus-Senftenberg, 03046 Cottbus, Germany
2 Ferdinand-Braun-Institut, Leibniz-Insitut für Höchstfrequenztechnik, 12489 Berlin, Germany
3 Technical University of Denmark, 2800 Kgs Lyngby, Denmark


double-heterojunction bipolar transistor (DHBT), electromagnetic (EM) simulation, small-signal modeling.