On the Nature of the Native Defect ESR in Thin Diamond Films

ABSTRACTThe X-band ESR of thin diamond films deposited from 99.5% H2/0.5% CH4 is compared to that of films similarly prepared from D2CD4 and H2/13CH4. The main line and the satellites at ±7.2 G are unaffected by annealing at T <. 1100°C, but their intensity is reduced upon annealing at T ∼ 1200°C. As the satellites are absent from the deuterated films, they are attributed to newly identified dangling bond-H centers, either on internal microvoid surfaces or embedded in the tetrahedral network. This is consistent with the 13C spin-lattice relaxation rate, which indicates that the distribution of paramagnetic centers is homogeneous to within ∼0.04 μm. However, they may be nonuniformly distributed on a finer scale, consistent with the concentrations in m ulti vacancies or stacking faults recently suggested by Fanciulli and Moustakas.