Characterization of hydrogen and silicon-related defects in CVD diamond by electron spin resonance

Two hydrogen and two silicon-related defect centers were detected and characterized by electron-spin resonance (ESR) in diamond films grown by chemical vapor deposition. Observation of hyperfine structure, combined with illumination and polishing treatments, suggests that the observed KUL2 and KUL9 ESR centers originate from two charge states of one defect, containing a vacancy and an adjacent hydrogen atom, while the KUL1 and KUL8 spectra can be associated with two charge states of another defect, involving one Si atom and exhibiting a trigonal symmetry. The KUL2 and KUL9 centers are tentatively assigned to negatively charged and neutral hydrogen-divacancy complexes, respectively.