Zeng Hui, Wu Meng, Cheng Meijuan, Lin Qiubao
College of Science, Hunan University of Science and Engineering, Yongzhou 425199, China.
Fujian Provincial Key Laboratory of Semiconductors and Applications, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Department of Physics, Xiamen University, Xiamen 361005, China.
Materials (Basel). 2023 Jul 28;16(15):5317. doi: 10.3390/ma16155317.
The intrinsic n-type conduction in Gallium oxides (GaO) seriously hinders its potential optoelectronic applications. Pursuing p-type conductivity is of longstanding research interest for GaO, where the Cu- and Zn-dopants serve as promising candidates in monoclinic β-GaO. However, the theoretical band structure calculations of Cu- and Zn-doped in the allotrope α-GaO phase are rare, which is of focus in the present study based on first-principles density functional theory calculations with the Perdew-Burke-Ernzerhof functional under the generalized gradient approximation. Our results unfold the predominant Cu and Zn oxidation states as well as the type and locations of impurity bands that promote the p-type conductivity therein. Furthermore, the optical calculations of absorption coefficients demonstrate that foreign Cu and Zn dopants induce the migration of ultraviolet light to the visible-infrared region, which can be associated with the induced impurity 3d orbitals of Cu- and Zn-doped α-GaO near the Fermi level observed from electronic structure. Our work may provide theoretical guidance for designing p-type conductivity and innovative α-GaO-based optoelectronic devices.
氧化镓（GaO）的本征n型导电性严重阻碍了其潜在的光电子应用。追求p型导电性一直是氧化镓长期以来的研究热点，其中铜和锌掺杂剂是单斜β-GaO中有前景的候选者。然而，关于铜和锌掺杂在同素异形体α-GaO相中的理论能带结构计算很少，这是本研究基于广义梯度近似下采用Perdew-Burke-Ernzerhof泛函的第一性原理密度泛函理论计算的重点。我们的结果揭示了主要的铜和锌氧化态以及促进其中p型导电性的杂质带的类型和位置。此外，吸收系数的光学计算表明，外来的铜和锌掺杂剂会导致紫外光向可见-红外区域迁移，这可能与从电子结构中观察到的铜和锌掺杂α-GaO在费米能级附近诱导的杂质3d轨道有关。我们的工作可能为设计p型导电性和创新的基于α-GaO的光电器件提供理论指导。
