Reliability concern of quasi-vertical GaN Schottky barrier diode under high temperature reverse bias stress

摘要

In this paper, the reliability of quasi-vertical GaN Schottky barrier diodes under high temperature reverse bias (HTRB) stress has been investigated. The test results indicate that the stress applied on the devices makes reverse leakage current decrease, but the forward performance, capacitance and reverse recovery performance show negligible changes. With the help of experiments and T-CAD simulations, it is demonstrated that there is trapping process of hot electrons along vertical sidewall of the device under high reverse voltage stress, which leads to the decrease of reverse leakage current. An empirical model can be used to predict the variations and good coincidences can be observed based on the acquired experiment data. Moreover, long time over voltage stress on the device leads to the direct failure. By using the infrared thermography analysis and T-CAD simulations, the failure mechanism has been also illustrated.