ESR studies of incorporation of phosphorus into high-pressure synthetic diamond

Electron spin resonance (ESR) signals associated with phosphorus, which should give microscopic evidence of incorporation of phosphorus into the lattice of diamond, have been searched in high-pressure synthetic diamond crystals. In a crystal grown from phosphorus catalyst, a new ESR spectrum labelled NIRIM-8 which exhibits both N-14 and P-31 hyperfine interactions has been found. In high-pressure synthetic type-IIa crystals implanted with high-energy (from 9 to 21 MeV) phosphorus ions at room temperature, ESR signals from point defects have been observed, after searching the implantation conditions which considerably lower the density of lattice damages. (C) 1997 Elsevier Science S.A.