High‐Performance GaN/BAs Heterojunctions: Dual Functionality of BAs for Enhanced Electrical and Thermal Management in Power Electronics

Benefit from the unusually outstanding thermal and electrical transport properties, the integration of cubic boron arsenide (BAs) with other semiconductors presents a promising avenue for advanced electronic and optoelectronic devices. However, assemblage of BAs-based devices poses significant challenges due to constraints in BAs growth conditions. In this study, gallium nitride/BAs (GaN/BAs) heterojunctions are fabricated using the surface-activated bonding method, achieving high-quality interfaces. The heterojunctions demonstrate a rectification ratio exceeding 10⁷, with atomic characterizations revealing enhanced performance at intermediate layer thicknesses below 20 nm. On the thermal front, BAs significantly improve heat dissipation outperforming GaN configurations under identical conditions. The fabrication of dual-functional BAs-based structures, where BAs works as an active p-type semiconductor and an efficient cooling substrate simultaneously, highlights its potential for next-generation power electronics, where both electrical performance and thermal management are crucial.