Mg掺杂氧化镓研究进展

doi:10.16553/j.cnki.issn1000-985x.2024.0295

摘要/Abstract

摘要： 氧化镓(Ga₂O₃)材料具有超宽禁带宽度、高击穿电场强度,在电力电子器件和光电器件领域具有巨大应用前景。虽然氧化镓难以实现p型导电,但仍可以利用p型掺杂调控能带实现电学性能设计。实验上已验证的氧化镓p型掺杂杂质有Mg、Fe、N、Zn、Cu、Ni、Co等,其中,Mg掺杂由于形成能最低、能级位置最靠近价带顶,以及掺入方法多而被大量研究。本文聚焦Mg掺杂,首先对Mg掺杂氧化镓的受主能级的理论计算认识和实验测试结果进行综述;接着总结了Mg掺杂氧化镓半绝缘单晶和外延层的各种掺杂方法、掺杂浓度,以及在热处理中Mg扩散等关键问题;最后指出关于Mg掺入、激活及扩散机制还值得进一步研究,并对其未来进行了展望。

关键词: 氧化镓, Mg掺杂, 半绝缘衬底, 电流阻挡层, 电学性能

Abstract: Gallium oxide (Ga₂O₃) possesses an ultra-wide bandgap and high breakdown electric field, making it promising for applications in power electronic devices and optoelectronic devices. Although Ga₂O₃ lacks p-type conductivity, we can still utilize p-type doping to control and design electrical properties by energy band engineering. The p-type dopants for gallium oxide that have been experimentally verified include Mg, Fe, N, Zn, Cu, Ni, Co, etc. Among the p-type dopants of Ga₂O₃, Mg is extensively studied due to its lowest formation energy, closest energy level to the valence band top, and multiple doping methods. This paper focuses on Mg doping β-Ga₂O₃. Firstly, the theoretical computational understanding and experimental test results of the acceptor levels of Mg-doped Ga₂O₃ are reviewed. Secondly, various doping methods, doping concentrations, and key issues such as Mg diffusion during thermal treatment for semi-insulating single crystals and epitaxial layers of Mg-doped β-Ga₂O₃ are summarized. Finally, it is pointed out that further investigations are needed on the mechanisms of Mg incorporation, activation and diffusion.

Key words: Ga₂O₃, Mg doping, semi-insulating substrate, current blocking layer, electrical property

中图分类号:

O483
O78

孙汝军, 张晶辉, 李一帆, 郝跃, 张进成. Mg掺杂氧化镓研究进展[J]. 人工晶体学报, 2025, 54(3): 361-370.

SUN Rujun, ZHANG Jinghui, LI Yifan, HAO Yue, ZHANG Jincheng. Review on Mg Doping of Ga₂O₃[J]. Journal of Synthetic Crystals, 2025, 54(3): 361-370.

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