Causes of Leakage Current in Vertical GaN P–N Diode under Reverse Bias

This article "Causes of leakage current in vertical GaN pn diode under reverse bias" by Tomoaki Sumi et al. (10.1002/pssb.202500026) explored the primary causes of reverse leakage current in GaN p–n junction diodes grown on freestanding GaN substrates. The authors concluded that nonuniform distribution of carrier concentration inside the GaN film can be one of the primary causes of large reverse leakage current - a factor primarily overlooked by traditional measurement techniques. The authors also reported the formation of pits with high incorporation of impurities, leading to an increase in the carrier concentration thereby suppressing the development of the depletion layer under reverse bias.