Comprehensive characterization of AlGaN/GaN metal‐oxide‐semiconductor high‐electron mobility transistors with TiO₂ gate dielectric

Abstract

AlGaN/GaN metal‐oxide‐semiconductor high‐electron mobility transistors (MOS‐HEMTs) on Si substrates with TiO2 gate dielectrics are fabricated. The dc and power characteristics of AlGaN/GaN MOS‐HEMTs are compared with that of metal‐gate HEMTs fabricated on the same material. The gate leakage current for the MOS‐HFET is more than two orders of magnitude smaller than for the HEMT at 300 K. The high‐speed performance potential of the MOS‐HEMT with an fT = 10.44 GHz and an fmax = 13.8 GHz is confirmed. The MOS‐HEMT shows higher extrinsic transconductance, breakdown voltage, high‐frequency and power characteristics relative to the HEMT. Furthermore, experimental results reveal that this studied MOS‐HEMT is feasible for use at high temperatures.