High-quality films were prepared by hot-filament chemical vapor deposition and were annealed (1300-1400C) in a vacuum or H atmosphere. The electron spin resonance spectrum did not change in shape and intensity for films annealed in a vacuum, but changed in shape for films annealed in H. This change could not be explained if the electron spin resonance signal was attributed to a single center such as H1. From computer simulations of the electron spin resonance spectrum, it was found that 2 further centers were necessary, besides the H1 center. The change in shape produced by annealing in H resulted from a change in the relative numbers of the 3 centers.

Effect of High-Temperature Annealing in Vacuum and Hydrogen on Paramagnetic Defects in Diamond Films Grown by Chemical Vapor Deposition. I.Watanabe, M.Yata, M.Kanatani, Y.Kawaguchi: Japanese Journal of Applied Physics - 1, 2002, 41[2A], 770-4

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