Frequency-Agile Packaged GaN-HEMT using MIM Thickfilm BST Varactors

S. Preis1, A. Wiens2, N. Wolff1, R. Jakoby2, W. Heinrich1, O. Bengtsson1

Published in:

Proc. 45th European Microwave Conf. (EuMC 2015), Paris, France, Sep. 7-10, pp. 1291-1294 (2015).

© 2015 EuMA. 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 EuMA.


Nowadays wireless communication systems demand flexibility along with electrical efficiency. In this work the highly efficient GaN-HEMT technology is combined with electrically tunable Barium-Strontium-Titanate MIM varactors in parallel-plate configuration, resulting in a frequency-agile transistor module. An efficiency improvement of 19% within a tuning voltage range of 400 V was measured. Maximum CW rating is 44.4 dBm output power at 71.8% drain efficiency. Thermal cycling and modulated-signal measurements verified highly stable and linear operation.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany
2 Institut fuer Mikrowellentechnik und Photonik, Technische Universitaet Darmstadt, Merckstrasse 25, 64283 Darmstadt, Germany


BST, power transistors, tunable devices, varactors.