The C(i)C(s)(Si(I))(n) Defect in Silicon from a Density Functional Theory Perspective

Carbon constitutes a significant defect in silicon (Si) as it can interact with intrinsic point defects and affect the operation of devices. In heavily irradiated Si containing carbon the initially produced carbon interstitial–carbon substitutional (C(i)C(s)) defect can associate with self-interstitials (Si(I)’s) to form, in the course of irradiation, the C(i)C(s)(Si(I)) defect and further form larger complexes namely, C(i)C(s)(Si(I))(n) defects, by the sequential trapping of self-interstitials defects. In the present study, we use density functional theory to clarify the structure and energetics of the C(i)C(s)(Si(I))(n) defects. We report that the lowest energy C(i)C(s)(Si(I)) and C(i)C(s)(Si(I))(2) defects are strongly bound with −2.77 and −5.30 eV, respectively.