Iridium Plug Technology for AlGaN/GaN HEMT Short-Gate Fabrication

K.Y. Osipov, R. Lossy, P. Kurpas, S.A. Chevtchenko, I. Ostermay, J. Würfl, and G. Tränkle

Published in:

Int. Conf. on Compound Semiconductor Manufacturing Technology (CS ManTech 2017), Indian Wells, USA, May 22-25, pp. 12.4 (2017).

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The purpose of this work is to introduce a novel concept for the AlGaN/GaN HEMT embedded gate fabrication. The novelty of the proposed gate fabrication method is to obtain a stress relief volume inside short embedded gates (150 nm and less). This volume compensates strain generated during device processing after gate module definition or during device operation. The presented technology was used for the fabrication of the mockup gates on GaAs substrates in order to confirm that the desired geometrical shape can be obtained. The mechanical simulation of conventional embedded gates and embedded gates with strain relief volume showed the effect of stress reduction during wafer cooling down to room temperature after transistor passivation process.

Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany


GaN HEMT, embedded gate technology, sputtered Ir, Au diffusion.