【Device Papers】Optimization of High-Breakdown SiC/Ga₂O₃ Heterojunction Diodes for Next-Generation Power Electronics

      Researchers from the George Mason University have published a dissertation titled " Optimization of High-Breakdown SiC/Ga₂O₃ Heterojunction Diodes for Next-Generation Power Electronics " in ECS Meeting Abstracts.

Abstract

      Achieving ultrahigh breakdown voltage while maintaining low conduction loss is a critical challenge in the development of next-generation power devices. Among wide- and ultrawide-bandgap (WBG/UWBG) materials, gallium oxide (Ga₂O₃) and silicon carbide (SiC) form a complementary pair: Ga₂O₃ delivers exceptional field tolerance with its 4.6–4.9 eV bandgap, while SiC combines a 3.26 eV bandgap and excellent thermal conductivity for robust high-power operation.

      Building on our previous demonstration of a high-breakdown SiC/Ga₂O₃ heterojunction diode, this study focuses on the optimization of device design through systematic TCAD simulations. Structural and doping parameters—including heterojunction length, doping concentration, and layer configuration—are carefully tuned to maximize breakdown voltage (BV), reduce specific ON-resistance (R_ON,sp), and enhance Baliga’s figure of merit (BFOM). Electric field analysis reveals how optimization redistributes high-field regions, suppresses premature breakdown, and enables improved trade-offs between blocking capability and conduction efficiency.

      The optimized heterojunction achieves a remarkable increase in BV from 1899 V to 4864 V with extended junction length, alongside reductions in (R_ON,sp) and improvements in BFOM. These results not only confirm the strong potential of SiC/Ga₂O₃ heterostructures as high-breakdown devices but also establish them as optimized, scalable candidates for efficient and reliable power conversion systems.

DOI：

https://doi.org/10.1149/MA2025-02373544mtgabs