Peculiarities of Neutron-Transmutation Phosphorous Doping of SiC Enriched with ~(30)Si Isotope: Electron Paramagnetic Resonance Study

摘要

High concentration of two types of P donors up to 10~(17) cm~(-3) in SiC enriched with ~(30)Si after neutron transmutation doping (NTD) has been achieved. It was established that annealing at sufficiently low temperature of 1300°C, that is 500-600°C lower compared with annealing of NTD SiC with natural isotope composition, gives rise to the EPR signal of shallow P donors, labeled sP_(c1), sP_(c2) and sP_h. The correlated changes of the EPR spectra of the three sP centres in all the experiments and the qualitative similarities with spectra of shallow N donors prove that these centres have shallow donor levels and a similar electronic structure and belong to different lattice sites. The annealing at 1700°C results in a transformation of one type of P donors (sP_(c1), sP_(c2) and sP_h) into another type having low temperature EPR spectra labeled dP.