Abstract Diffusion of native point defects is examined in the interface region of the InN/GaN heterostructure grown in hexagonal c direction. Heights of migration energy barriers of single vacancies and their complexes with substitutional group-III element are calculated in bulk GaN and InN crystals for two diffusion mechanisms, as well as across the InN/GaN heterointerface. An impact of the in-plane strain, the influence of built-in electric field, as well as the presence of electric dipole on vacancy motion is analysed. The obtained results show that metal vacancies V Ga and V In can migrate across the InN/GaN interface overcoming a potential energy barrier lower than that of V N . Moreover, the smallest energy barrier is related to the in-plane migration of V In what can favor spatial segregation of In atoms near the InN/GaN interface. This phenomenon can significantly contribute to the thermal degradation process of InGaN/GaN QWs, often observed experimentally both during the operation of nitride devices, as well as at the stage of their growth.

中文翻译：

---

通过伪晶和晶格匹配 InN/GaN 界面的点缺陷迁移的 DFT 研究

摘要 在六方 c 方向生长的 InN/GaN 异质结构的界面区域中检查了本征点缺陷的扩散。在块状 GaN 和 InN 晶体中针对两种扩散机制以及 InN/GaN 异质界面计算了单个空位及其与置换 III 族元素的复合物的迁移能垒高度。分析了面内应变的影响、内置电场的影响以及电偶极子的存在对空位运动的影响。获得的结果表明，金属空位 V Ga 和 V In 可以跨越 InN/GaN 界面迁移，克服比 VN 低的势垒。此外，最小的能垒与 V In 的面内迁移有关，V In 有利于 InN/GaN 界面附近 In 原子的空间分离。