Improved breakdown characteristic of AlGaN/GaN HEMTs with a width gradient recessed dual-gate structure

Abstract

A dual-gate (DG) structure utilizing an integrated width gradient DC gate to balance the high-voltage and output current drop was performed for the fabrication of AlGaN/GaN high-electron-mobility transistor (HEMT). In comparison to the traditional single-gate devices, the DG HEMTs combine significantly allowable breakdown voltage behaviour with low gate leakage current and a positive shift threshold voltage, delivering one order of magnitude reduction in leakage current and a 36% improvement in maximum drain bias. The evaluated S parameters substantially exhibit a high power gain potential for DG devices due to the presence of DC gate.