High-temperature characteristics of Al_<i>x</i>Ga_1−<i>x</i>N/GaN Schottky diodes

Abstract

High-temperature characteristics of the metal/AlxGa1−xN/GaN M/S/S (M/S/S) diodes have been studied with current–voltage (I–V) and capacitance–voltage (C–V) measurements at high temperatures. Due to the presence of the piezoelectric polarization field and a quantum well at the AlxGa1−xN/GaN interface, the AlxGa1−xN/GaN diodes show properties distinctly different from those of the AlxGa1−xN diodes. For the AlxGa1−xN/GaN diodes, an increase in temperature accompanies an increase in barrier height and a decrease in ideality factor, while the AlxGa1−xN diodes are opposite. Furthermore, at room temperature, both reverse leakage current and reverse breakdown voltage are superior for the AlxGa1−xN/GaN diodes to those for the AlxGa1−xN diodes.