【Member Papers】Researchers from the Xidian University has introduced a novel NixO/SiNx/Ga₂O₃ sandwich structure, effectively enhancing the performance of the β-Ga₂O₃ diode

      The emerging ultra-wide bandgap semiconductor β-Gallium oxide (Ga₂O₃) is eliciting an incredible amount of interest. Primarily research on Ga₂O₃ devices focuses on increasing the reverse breakdown voltage, with relatively less emphasis on achieving low on-state resistance and high current density. Many reported gallium oxide diodes exhibit lower current density, due to the low mobility of Ga2O3. Various methods have been employed to enhance current density and reduce on-state resistance, including increasing the electron concentration in the epitaxial layer, using thin epitaxial layers, and thinning the substrate. However, it is important to note that higher doping concentration or ultra-thin epi-layers can result in a lower breakdown voltage (BV), and thinning the Ga₂O₃ substrate for large-scale engineering applications is challenging due to the fragility of Ga₂O₃ crystalline structure.

      In this study, we proposed a novel Ni_xO/SiN_x/Ga₂O₃ sandwich structure, demonstrating enhancing performance of β-Ga₂O₃ diodes, particularly making significant progress in forward current density and on-state resistance. With the sandwich structure, we achieved an extremely high forward current density of over 1 kA/cm² at a 2 V forward bias, along with a low on-state resistance of only 1.1 mΩ·cm². Simultaneously, a high breakdown voltage of 476 V was also achieved. This work provides an innovative approach for designing high-current Ga₂O₃ power electronic devices and establishes a substantial experimental foundation for improving the performance of Ga₂O₃ power electronic devices.

      This work, titled "Enhancing performance of β-Ga₂O₃ diodes through a Ni_xO/SiN_x/Ga₂O₃ sandwich structure," has been published in the "Journal of Alloys and Compounds."

Corresponding author: Zheng Xuefeng, professor of Xidian University, leading professor of "Huashan Scholars", doctoral supervisor and national leading talent.

He has long been engaged in research on defect characterization of semiconductor devices, structure and process of new wide band gap semiconductor devices, reliability evaluation, etc. He has published more than 100 academic papers and more than 50 invention patents. He has undertaken more than 20 key/general/youth projects of the National Natural Science Foundation, major national science and technology special projects, national key research and development plan projects, and horizontal projects. He has won the first prize of the National Science and Technology Progress Award, the first prize of the National Teaching Achievement Award, the first prize of the Shaanxi Provincial Science and Technology Progress Award, the Ministerial Innovation Team Award, the Special Prize of the Shaanxi Provincial Education and Teaching Achievements, and the Shaanxi Provincial Youth Science and Technology Award.

Paper Link：https://doi.org/10.1016/j.jallcom.2023.173062