Electrical and optical characterisation of silicon and silicon phosphorus implants in InP doped with iron

Silicon implantations into semi-insulating InP with a wide range of doses and energies have been carried out with the aim of obtaining n type layers suitable for device applications. The electrical activations obtained were typically about 70%, reaching 80% for Si/P co-implants with a dose of 10(14) cm(-2), and the electrical depth profiles showed no redistribution of the implants during annealing. The mobilities obtained after all rapid thermal annealing cycles used were very high, indicating the good crystalline quality of the resulting layers. This was confirmed by Raman scattering measurements, which showed that even if the material is completely amorphised by the implantation, the annealing treatment restores the emissions found for as received unimplanted InP. After Si implantation, the photoluminescence spectrum of the samples showed the appearance of a band at 1.17 eV with high thermal stability, the origin of which was tentatively assigned to v(p)-Si-p (P vacancy-Si on P lattice site) complexes. (C) 1995 The Institute of Materials.