Effect of local fields on the Mg acceptor in GaN films and GaN substrates
Effect of local fields on the Mg acceptor in GaN films and GaN substrates
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局部场对 GaN 薄膜和 GaN 衬底中 Mg 受体的影响
DOI：
10.1063/1.4963112
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发表时间：
2016
影响因子：
3.2
通讯作者：
K. Udwary
中科院分区：
文献类型：
--
作者：
M. Zvanut;J. Dashdorj;U. Sunay;J. Leach;K. Udwary
研究了各种 GaN 样品（包括毫米厚的独立衬底和亚微米异质外延膜）中 Mg 受体的电子顺磁共振 (EPR) 谱。前者允许在位错小于 107 cm−3 且掺杂密度范围为 4 × 1016 至 6 × 1018 cm−3 的环境中观察 EPR 独特的受体。在一项研究中，通过在广泛的样品中探测镁，受体的一个新特征出现了。 EPR 数据揭示了各向异性线形状，反映了 Mg 受体附近晶体场的变化。为 Mg 受体提出的任何模型都必须适应此功能。在这里，我们证明了先前提出的一种模型与从各种研究样本中获得的 EPR 数据非常吻合。这项工作表明，镁掺杂的 GaN 含有常见的镁相关缺陷，该缺陷可能会受到生长过程中建立的局部晶体场的影响。
The electron paramagnetic resonance (EPR) spectrum of the Mg acceptor is studied in a variety of GaN samples, including mm-thick free-standing substrates and sub-micron heteroepitaxial films. The former allows a view of the acceptor unique for EPR—in an environment with less than 107 cm−3 dislocations and doping densities ranging from 4 × 1016 to 6 × 1018 cm−3. By probing Mg in a broad range of samples in one study a new feature of the acceptor emerges. The EPR data reveal an anisotropic line shape that reflects a change in the crystal field in the vicinity of the Mg acceptor. This feature must be accommodated by any of the models proposed for the Mg acceptor. Here, we show that one such previously proposed model agrees well with the EPR data obtained from the wide variety of samples studied. The work implies that Mg-doped GaN contains a common Mg-related defect which can be affected by local crystal fields established during growth.