Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Towards highly-integrated high-voltage multi-MHz GaN-on-Si power ICs and modules

: Moench, S.; Reiner, R.; Weiss, B.; Waltereit, P.; Quay, R.; Kaden, T.; Ambacher, O.; Kallfass, I.

MESAGO PCIM GmbH, Stuttgart:
PCIM Europe 2018, International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. Proceedings : Nuremberg, 05 - 07 June 2018, CD-ROM
Berlin: VDE-Verlag, 2018
ISBN: 978-3-8007-4646-0
ISBN: 3-8007-4646-8
PCIM Europe <2018, Nuremberg>
Fraunhofer IAF ()

This work investigates how integration of half-bridge transistors, drivers and freewheeling-diodes on a conductive Si-substrate influences DC-DC converter performance. Based on a lateral 600 V GaNtechnology, a 300-150V, 750W buck converter is built. Conventional separate substrate-to-source terminations of the high-side and low-side devices resulted in 97.3% maximum efficiency. A common semi-floating substrate termination as applicable to monolithic ICs reduced the maximum efficiency to 96.8%, but improved no-load losses. Capacitance measurements which include the substrate as terminal explain two opposite effects resulting from the common substrate: Increased Miller capacitance slows down hard-switching turn-on transitions; reduced effective switch-node capacitance speeds up resonant transitions. Operating the integrated GaN driver with external Si-CMOS pre-driver in burst operation up to 40MHz at 350 V shows potential for multi-MHz applications. While monolithic integration is beneficial to reduced parasitic inductances and assembly effort, a differentiated analysis considering different switching conditions is required to identify system-level advantages.