10 kV Ga2O3 Charge-Balance Schottky Rectifier Operational at 200 °C

• Published in: IEEE electron device letters 2023-06, Vol.44 (8), p.1-1
• Main Authors: Qin, Yuan, Xiao, Ming, Porter, Matthew, Ma, Yunwei, Spencer, Joseph, Du, Zhonghao, Jacobs, Alan G., Sasaki, Kohei, Wang, Han, Tadjer, Marko, Zhang, Yuhao
• Format: Article
• Language: English
• Subjects: Anodes; Electric fields; Gallium; gallium oxide; Gallium oxides; High temperature; high voltage; High voltages; Microbalances; nickel oxide; Nickel oxides; Power electronics; RESURF; Schottky barriers; Schottky diode; Schottky diodes; Temperature measurement; Thermal stability; ultra-wide bandgap
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2023.3287887

This work demonstrates a lateral Ga 2 O 3 Schottky barrier diode (SBD) with a breakdown voltage ( BV ) over 10 kV, the highest BV reported in Ga 2 O 3 devices to date. The 10 kV SBD shows good thermal stability up to 200 °C, which is among the highest operational temperatures reported in multi-kilovolt Ga 2 O 3 devices. The key device design for achieving such high BV is a reduced surface field (RESURF) structure based on the p-type nickel oxide (NiO), which balances the depletion charges in the n-Ga 2 O 3 channel at high voltage. At BV , the charge-balanced Ga 2 O 3 SBD shows an average lateral electric field (E-field) over 4.7 MV/cm at 25 °C and over 3.5 MV/cm at 200 °C, both of which exceed the critical E-field of GaN and SiC. The 10 kV SBD shows a specific on-resistance of 0.27 Ω∙cm 2 and a turn-on voltage of 1 V; at 200 °C, the former doubles and the latter reduces to 0.7 V. These results suggest the good potential of Ga 2 O 3 devices for medium-and high-voltage, high-temperature power applications.