Multilayer SiNx passivated Al2O3 gate dielectric featuring a robust interface for ultralong-lifetime AlGaN/GaN HEMT

This paper presents a multilayer SiNx passivation-based robust and high-reliability interface for effective suppression of current collapse effect and reduction of leakage current at AlGaN/GaN heterostructure. The performance characterization of the fabricated HEMT reveals a high drain saturation current, peak extrinsic transconductance (up to 199.5 mS/mm), and dynamic RON/static RON of 1.067 even at a high drain voltage of 700 V. Moreover, an excellent mean time-to-failure of 2.204 × 108 h at an activation energy of 2.621 eV at TC = 150 °C is obtained, which indicates that the developed HEMT exhibits an ultralong operation lifetime for RF power applications.