The influence of the GaN substrate types and active area scaling design on the conduction properties of vertical GaN MISFETs for laser driving applications

E. Bahat Treidel1, O. Hilt1, V. Hoffmann1, F. Brunner1, B. Janke1, N. Bickel1, H. Yazdani1, H. Gargouri2 and J. Würfl1

Published in:

Int. Conf. on Compound Semiconductor Manufacturing Technology (CS ManTech 2020), Dig., pp. 229-232 (2020).

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In this work we present a systematic study on the conduction properties in vertical GaN trench MISFETs grown and manufactured on different free standing GaN substrates. It is shown that devices manufactured on ammonothermal substrates have superior conduction current density higher than 4 kA/cm2, specific ON-state resistance as low as 1.1 ± 0.1 mΩcm2 and channel sheet resistance of 19.6 ± 0.9 Ωmm. It is further shown that scaling these devices to large gate periphery is not limited by current spreading in the drift region, low channel mobility or by self-heating. The conduction properties of devices manufactured on ammonothermal GaN substrates are found to be the most suitable for pulsed laser driving applications.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik (FBH), Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany
2 SENTECH Instruments GmbH, Schwarzschildstr. 2, 12489 Berlin, Germany


Vertical GaN trench MISFETs, GaN substrates, Ammono-thermal, HVPE, Active area scaling.