Cubic AlGaN/GaN Hetero‐Junction Field‐Effect Transistors with Normally‐on and Normally‐off Characteristics

The growth of cubic group III‐nitrides is a direct way to eliminate polarization effects, which inherently limit the fabrication of normally‐off hetero‐junction field‐effect transistors (HFETs) in GaN technology. HFET structures were fabricated of non‐polar cubic AlGaN/GaN hetero layers grown by plasma assisted molecular beam epitaxy on free standing 3C‐SiC (001). The electrical insulation of 3C‐SiC was realized by $Ar+$ implantation before c‐AlGaN/GaN growth. HFETs with normally‐off and normally‐on characteristics were fabricated of cubic AlGaN/GaN. Capacitance‐voltage characteristics of the gate contact were performed to detect the electron channel at the c‐AlGaN/GaN hetero‐interface.