On the Abnormal Reduction and Recovery of Dynamic <i>R</i> <sub>ON</sub> Under UIS Stress in Schottky p-GaN Gate HEMTs
Chao Liu, Xinghuan Chen, Ruize Sun, Jingxue Lai, Wanjun Chen, Yajie Xin, Fangzhou Wang, Xiaoming Wang, Zhaoji Li, Bo Zhang
Abstract
In this letter, the abnormal reduction and recovery of dynamic <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> are observed under unclamped-inductive-switching (UIS) stress in Schottky p-GaN gate HEMTs. The reduction of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON_dyn</sub> exhibits a positive dependence on UIS stress ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PEAK</sub> , peak voltage). With the help of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Sentaurus</i> simulation, the underlying physical mechanism is revealed. During UIS stress, the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">e-h</i> pairs generated by impact ionization can be trapped, and the detrapping of electrons is faster than holes because of the lower time constant, which results in the reduction of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON_dyn</sub> . Furthermore, a mathematic model of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON_dyn</sub> after UIS stress is developed and verified by measurement. This work could provide practical guidance for the UIS operation setup to reduce the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> and conduction loss of GaN HEMTs.