ESR study of phosphorus implanted type IIa diamond

Cold Implantation and Rapid Annealing (CIRA) at 1050 degrees C of P in IIa diamond crystal, then further annealing at 1400 degrees C were performed. E PR signals were obtained in particular (i) around g = 2.003, from "dangling bond" defects whose total concentration increases with the dose and decrea ses after annealing, but remains higher than the dose, (ii) a pair of isotr opic symmetrical signals with a constant Delta H = 28 G independent of the dose and of annealing were detected. They are ascribed to paramagnetic P in substitutional sites. For the highest dose after annealing, an IR absorpti on can be detected at energies corresponding to transitions between the fun damental and the excited levels of the effective mass like P donor center i n diamond. The calculated donor density from IR is in agreement with the de nsity of spins in the 28 G hyperfine lines.