2.3 Kv Al-rich AlGaN Channel HEMTs on Sapphire with >2.2 MV Cm−1 Average E-Field and >650 MW Cm−2 Baliga Figure of Merit

Al-rich AlGaN is a strong candidate for high-voltage power electronics, yet high-performance [>500 MW cm(-2) Baliga figure of merit (BFOM)] passivated AlGaN channel transistors on cost-effective sapphire remain limited. We demonstrate passivated, field-plated Al0.6Ga0.4N HEMTs achieving 2.33 kV breakdown with >2.2 MV cm(-1) average breakdown field. The device demonstrates 8.32 m Omega & centerdot;cm(2) on-resistance and a record 654 MW cm(-2) BFOM (>1 kV). With similar to 5.5 mu m gate-drain spacing, devices reach >2.5 MV cm(-1) and 556 MW cm(-2) BFOM, highlighting excellent field management and strong potential for scalable, cost-effective sapphire-based platforms.