GaN Power p–n Diodes on Hydride Vapor Epitaxy GaN Substrates with Near‐Unity Ideality Factor and <0.5 mΩ cm²Specific On‐Resistance

Herein, vertical GaN p–n diodes grown by metal organic chemical vapor deposition on hydride vapor epitaxy bulk GaN substrates are reported. The devices exhibit an ideality factor of 1.15, a turn‐on voltage of 3.2 V at 100 A cm⁻², over 1 kV breakdown voltage, and specific on‐state resistance of 0.47 mΩ cm², leading to a Baliga's figure of merit of ≈2.2 GW cm⁻². The low specific on‐resistance, low turn‐on voltage, and the near‐unity ideality factor demonstrated here are attributed to the high epitaxial material quality and optimized low anode contact resistance.