β相氧化镓p型导电研究进展

doi:10.16553/j.cnki.issn1000-985x.2024.0285

摘要/Abstract

摘要： β相氧化镓(β-Ga₂O₃)具有超宽带隙、高击穿电场和容易制备等优势,是功率器件的理想半导体材料。但由于β-Ga₂O₃价带顶能级位置低、能带色散关系平坦,其p型掺杂目前仍具有挑战性,限制了p-n结及双极性晶体管的开发。利用尺寸效应、缺陷调控、非平衡动力学及固溶提升价带顶能级等方案是目前实现β-Ga₂O₃ p型掺杂的主要策略。对于β-Ga₂O₃ p-n同质结和异质结,提高晶体质量、减少界面缺陷态是优化器件性能的关键问题。本文针对β-Ga₂O₃的p型导电问题,系统阐述了β-Ga₂O₃电子结构,实验表征及理论计算掺杂能级方法,p型掺杂困难原因,以及改进p型掺杂的突破性研究进展。最后简单介绍了β-Ga₂O₃ p-n同质结和异质结器件的相关工作。利用复合缺陷调控、非平衡动力学、固溶等方案,以及不同方案的协同实现体相β-Ga₂O₃的p型掺杂仍需要深入探索,p-n同质及异质结的器件性能需要进一步优化。

关键词: β-Ga₂O₃, p型导电, 电子结构, 受主能级, 固溶, p-n结

Abstract: β phase gallium oxide (β-Ga₂O₃) is an ideal semiconductor material for power devices based on its ultra-wide bandgap, high breakdown electric field, and easy preparation. However, it is still challenging to realize p-type doping of the β-Ga₂O₃ because of its relatively low energy of valence band maximum (VBM) and flat band dispersion near the VBM, which limits the development of p-n junctions and bipolar transistors. The main strategies for the p-type doping of β-Ga₂O₃ in recent research are based on size effect, defect regulation, non-equilibrium dynamic process, and solid solution. For the β-Ga₂O₃ p-n homojunction and heterojunction, improving crystal quality and reducing the interface defect states are the key issues for optimizing devices’ performances. This paper focuses on the p-type conductivity problem of β-Ga₂O₃, systematically reviews the electronic structure of β-Ga₂O₃, the experimental characterization and theoretical calculation method of doping levels, the reasons for p-type doping difficulty, and the breakthrough in research advancements for improving the p-type doping of β-Ga₂O₃. Finally, the relevant studies on the β-Ga₂O₃ p-n homojunction and heterojunction devices are briefly reviewed. It requires further exploration to realize p-type doping of bulk-phase β-Ga₂O₃ through complex-defect regulation, non-equilibrium dynamics, solid solution, and combining these schemes. The device performances of p-n homojunction and heterojunction also need further optimization.

Key words: β-Ga₂O₃, p-type conduction, electronic structure, acceptor level, solid solution, p-n junction

中图分类号:

查显弧, 万玉喜, 张道华. β相氧化镓p型导电研究进展[J]. 人工晶体学报, 2025, 54(2): 177-189.

ZHA Xianhu, WAN Yuxi, ZHANG Daohua. Research Progress on p-Type Conduction of β Phase Gallium Oxide[J]. Journal of Synthetic Crystals, 2025, 54(2): 177-189.

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