2025年10月6日～9日にフランス・ボルドーで開催された材料・デバイス・回路の品質・信頼性分野の国際学会ESREF 2025（European Symposium on Reliability of Electron Devices, Failure Physics and Analysis）にて、豊田合成株式会社と名古屋大学の論文が採択されました。ESREFは半導体や電子材料に関する研究を深めるための国際的なシンポジウムで、半導体をはじめとするさまざまな電子材料の物理化学、そのエレクトロニクスへの応用について多様な研究成果が共有され、自由に討論される場が提供されます。

A paper co-authored by Toyota Gosei Co., Ltd. and Nagoya University has been accepted for presentation at ESREF 2025 (European Symposium on Reliability of Electron Devices, Failure Physics and Analysis), an international conference on the quality and reliability of materials, devices, and circuits. The conference will be held in Bordeaux, France, from October 6 to 13, 2025. ESREF is an international symposium designed to deepen research on semiconductors and electronic materials. It provides a forum for sharing diverse research findings on the physical chemistry of various electronic materials, including semiconductors, and their applications in electronics, fostering open discussion.

 

“10 kW Inverter with Vertical-GaN Trench MOSFETs and Its Operation Instability Related to MOS Interface”
Vertical GaN metal-oxide-semiconductor field-effect transistors (MOSFETs) are suitable for highly efficient power conversion in high-power systems. This study demonstrates three-phase inverter operation using vertical GaN trench MOSFETs capable of the gate overdriving up to 20 V. The fabricated MOSFETs showed minimal variations in the threshold voltage (Vth) and on-resistances (Ron), which allowed the parallel connection of four devices in high or low side of each phase. The output power reached 10.4 kW. After inverter operation, the devices showed the Vth shift and the increase of Ron, where the respective degradations depended on an Mg concentration in a p-type body and driving current. The Vth shift resulted from electron injected to near interface traps on the channel region, while the Ron increase was likely caused by injecting hot electrons into the access region similar to the dynamic Ron in a GaN HEMT. Optimization of the MOS interface would lead to stable device performance.