Effect of high voltage stress on the DC performance of the Al2O3/AlN GaN metal-insulator-semiconductor high-electron mobility transistor for power applications

Abstract

We demonstrate an Al2O3/AlN/AlGaN/GaN metal-insulator-semiconductor high-electron mobility transistor (MIS-HEMT) device with stable electrical properties under high-voltage stress, by using an Al2O3/AlN stack layer as the gate dielectric layer. Excellent quality AlN/Al2O3 GaN interface was obtained by using plasma-enhanced ALD (PE-ALD), resulting in a very low interface trap density (D-it) of similar to 1.8 x 10(11) eV(-1) cm(-2), obtained by using the conductance method. The device exhibits a small threshold voltage hysteresis of similar to 200 mV and a lower gate-source leakage current. No obvious changes in the drain-source current and ON-resistance were observed for the device that was subject to the drain-source voltage stress of 100 V for 15 h. (C) 2015 The Japan Society of Applied Physics