Investigation of constant voltage off-state stress on Au-free AlGaN/GaN Schottky barrier diodes

Abstract

In this work, we perform an in-depth analysis of electron-trapping in AlGaN/GaN Schottky barrier diodes under constant voltage (V AC = %100 V) off-state stress conditions. The current-voltage (I-V) characteristics of the diode after stressing show a leakage reduction and on-state degradation due to electron-trapping occurring in the vicinity of the Schottky contact. Capacitance-voltage (C-V) measurements confirm an increase of the barrier height and the on-resistance of the stressed device. Furthermore, the on-resistance increase has been studied with different temperatures and stressing times. By TCAD simulations, a lateral extension of the "trapped region" at the AlGaN/Si 3 N 4 interface has been visualized and can qualitatively explain the phenomenon of higher on-resistance increase at higher temperatures.

Leakage and trapping characteristics in Au‐free AlGaN/GaN Schottky barrier diodes fabricated on C‐doped buffer layers

“…The dynamic characteristics of the GET‐SBD on two buffers have been performed by using a measurement procedure reported in (). When the AlGaN/GaN SBD is subject to a high reverse voltage, the 2DEG in the vicinity of the anode contact is depleted and the depletion region extends in the lateral direction towards the cathode contacts . The electrons can be injected from the anode contact into the GaN channel and in the buffer leading to the leakage current and trapping phenomena.…”