First-principles calculations were carried out to investigate the stable and potential metastable structure of neutral and charged self-interstitial atoms (SIAs) in 3C-SiC. Besides, we have systematically studied the most likely rotation and migration paths of these SIAs. The calculated activation energy for the full space rotation of C, C²⁺, Si and Si⁴⁺ interstitials are 0.48 eV, 0.59 eV, 0.73 eV and 0.43 eV, respectively. The migration energy barrier for the long-distance diffusion of C, C²⁺, Si and Si⁴⁺ interstitials are 0.71 , 1.57 , 0.73 and 3.15 eV. The charge state can not only affect the energy barrier of SIAs but also change the migration path. In general, this work can provide a comprehensive picture describing the full space rotation and long-distance migration of SIAs, and the energy barriers in this work are in good agreement with previous defect annealing experiments and simulation results.

进行第一性原理计算以研究 3C-SiC 中中性和带电自填隙原子 (SIA) 的稳定和潜在亚稳态结构。此外，我们系统地研究了这些 SIA 最可能的轮转和迁移路径。C、C ²⁺、Si 和Si ⁴⁺间隙的全空间旋转的计算活化能分别为0.48 eV、0.59 eV、0.73 eV和0.43 eV。C、C ²⁺、Si、Si ⁴⁺长距离扩散的迁移能垒间隙为 0.71、1.57、0.73 和 3.15 eV。电荷状态不仅会影响 SIA 的能垒，还会改变迁移路径。总的来说，这项工作可以提供描述SIAs全空间旋转和长距离迁移的全面图片，并且这项工作中的能垒与先前的缺陷退火实验和模拟结果非常吻合。