Analysis on abnormal forward conduction properties in GaN based JBS diode by TCAD simulation

• Published in: 2022 19th China International Forum on Solid State Lighting & 2022 8th International Forum on Wide Bandgap Semiconductors (SSLCHINA: IFWS) pp. 82 - 86
• Main Authors: Zhang, Qi, Wu, Qianshu, Wang, Yapeng, Qiu, Qiuling, Liu, Zhenxing, Zhang, Jinwei, Li, Chenglang, Zhou, Yuhao, Liu, Yang
• Format: Conference Proceeding
• Language: English
• Published: IEEE 07.02.2023
• DOI: 10.1109/SSLChinaIFWS57942.2023.10070928

Abnormal phenomenon that on-resistance of JBS diode increases with forward bias has been studied in this work. It is found that the forward bias is mainly applied to the p-type Schottky junction, resulting in a slower electric potential increasing rate of p-GaN than n-type channel between adjacent p-grid. Therefore, the lateral PN junction at channel is reversely biased and the effective conduction area of JBS diode reduces, which results in the increase of on-resistance. JBS diodes with different Schottky barrier height at p-type Schottky contact are also simulated to verify our analysis. The decrease of barrier height at p-type Schottky junction results in that the anode voltage is mainly applied to the PN junction, which can shorten the lateral depletion region and decrease the on-resistance of JBS diode. The simulation results in this paper are useful for providing reference advice for following experiments.