Dependence of Gate Leakage Current on Efficacy of Gate Field Plate in AlGaN/GaN HEMT

GaN HEMTs finds applications in Radio Frequency (RF) and high-power device and sensing applications. Several types of GaN HEMT device structures have been studied and are being used in various forms. In this article, a comparative study of gate field plated device with a conventional GaN HEMT device has been studied. A close relationship in gate leakage current with off-state breakdown pattern has been observed. The field plate starts working after a certain rise in the gate-drain electric field creating a hump in off-state breakdown characteristic. In low gate leakage device this pattern is absent signifying the effectiveness of gate field plate in fix voltage range.