ANTISITES DEFECTS IN GAP

ESR, optical, and transport measurements were done on neutron-irradiat ed GaP crystals subjected to thermal annealing. The behavior of two do minant paramagnetic defects: phosphorus antisite PP4 and WA1 [1] was f ollowed. ESR signal similar to WA1 was earlier attributed to the defec t related with gallium antisite [2]. Our thermal annealing experiments supported such attribution. Apart from that, the obtained results ind icated that two dominant absorption bands in neutron-irradiated GaP wi th maxima at 0.79 and 1.13 eV [1] were not connected with PP4 or WA1 d efects. However, one of these paramagnetic defects (or two of them) we re responsible for hopping transport in n-irradiated GaP crystals.