Silicon carbide (SiC) has been considered one of the most important wide bandgap semiconductors for both scientific interest and technological applications. The existence of stacking faults induced inclusions, originated from the “wrong” stacking sequences of Si–C bilayers, is a general feature in SiC. Until now, however, a systematical understanding of the role of cubic inclusions (CIs) in the electronic and doping properties of hexagonal SiC is still lacking, which may prevent further improvement of its electronic performance. In this article, using advanced first-principles calculations, we have systematically studied the stability, electronic structures, and doping properties of hexagonal SiC with CIs. First, we find that the CIs in SiC have rather low formation energies but high kinetic stability. Second, we find that the electronic structures of SiC can be dramatically tuned by the ratio of CIs in SiC. Third, we demonstrate that the CI-induced band offset and the dipole-discontinuity-induced dipole field in the system can give rise to different ground-state doping sites for dopants at their different charge-states, which can consequently result in novel doping-site-dependent charge-state transition levels (CTLs). Meanwhile, the intrinsic dipole field can dramatically enhance the structural relaxation effects during the ionization of the dopants, which can push the CTLs deeper inside the bandgap compared to the case without CIs. Our findings suggest that CIs could play unusual roles in determining the overall electronic and doping properties of SiC and other similar semiconductors.

中文翻译：

---

具有层错诱导立方体夹杂物的六方碳化硅的电子和掺杂特性

碳化硅 (SiC) 被认为是对科学兴趣和技术应用最重要的宽带隙半导体之一。堆垛层错诱发夹杂物的存在，源于“错误的”Si-C 双层堆叠序列，是 SiC 的一个普遍特征。然而，到目前为止，仍然缺乏对立方夹杂物（CIs）在六方碳化硅电子和掺杂特性中的作用的系统理解，这可能会阻碍其电子性能的进一步提高。在本文中，我们使用先进的第一性原理计算，系统地研究了具有 CI 的六方 SiC 的稳定性、电子结构和掺杂特性。首先，我们发现 SiC 中的 CIs 具有相当低的形成能但具有很高的动力学稳定性。其次，我们发现 SiC 中 CI 的比例可以显着调整 SiC 的电子结构。第三，我们证明了系统中 CI 引起的带偏移和偶极子不连续性引起的偶极子场可以为处于不同电荷状态的掺杂剂产生不同的基态掺杂位点，从而导致新的掺杂位点 -依赖的电荷态转换能级 (CTL)。同时，本征偶极场可以显着增强掺杂剂电离过程中的结构弛豫效应，与没有 CI 的情况相比，这可以将 CTL 推入更深的带隙内。我们的研究结果表明，CI 可以在确定 SiC 和其他类似半导体的整体电子和掺杂特性方面发挥不同寻常的作用。在掺杂剂电离期间，本征偶极场可以显着增强结构弛豫效应，与没有 CI 的情况相比，这可以将 CTL 推入更深的带隙内。我们的研究结果表明，CI 可以在确定 SiC 和其他类似半导体的整体电子和掺杂特性方面发挥不同寻常的作用。在掺杂剂电离期间，本征偶极场可以显着增强结构弛豫效应，与没有 CI 的情况相比，这可以将 CTL 推入更深的带隙内。我们的研究结果表明，CI 可以在确定 SiC 和其他类似半导体的整体电子和掺杂特性方面发挥不同寻常的作用。