An electron paramagnetic-resonance study of diamond films doped by implantation of phosphorus during film deposition is reported. Samples with nominal phosphorus concentration between 1016 and 1017 cm-3 exhibit two isotropic lines of equal intensity separated by 27 G. The double-line spectrum is expected for a nuclear-spin 1/2 species such as phosphorus. The symmetry of the center and the temperature dependence of the spin concentration suggest that phosphorus forms a substitutional shallow donor in diamond. © 1994 American Institute of Physics.
