Reactive sputtering of Al2O3 on AlGaN/GaN heterostructure field-effect transistor

AlGaN/GaN heterostructure field-effect transistor has great potential for use in high voltage, high current and high power device applications. To reduce the gate leakage current, generally oxide layers are employed. Using an Al2O3 layer as a gate oxide layer, effects on the device performances were investigated. Leakage current density and current–voltage characteristics of AlGaN/GaN heterostructure field-effect transistor with Al2O3 layer were measured, the drain current was about 510 mA/mm at Vgs = 1 V and the gate leakage current density was lowered with Al2O3 layer.