Device characteristics of AlGaN/GaN MIS-HEMTs with high-k HfxZr1-xO2 (x = 0.66, 0.47, 0.15) insulator layer
Abstract This study investigates the characteristics of AlGaN/GaN MIS–HEMTs with Hf x Zr 1 − x O 2 ( x  = 0.66, 0.47, and 0.15) high- k films as gate dielectrics. Sputtered Hf x Zr 1 − x O 2 with a dielectric constant of 20–30 and a bandgap of 5.2–5.71 eV was produced. By increasing the Zr content of HfZrO 2 , the V TH shifted from −1.8 V to −1.1 V. The highest Hf content at this study reduced the gate leakage by approximately one order of magnitude below that of those Zr-dominated HFETs. The maximum I DS currents were 474 mA/mm, 542 mA/mm, and 330 mA/mm for Hf content of 66%, 47%, 15% at V GS  = 3 V, respectively.