FORMATION OF N(-LAYERS IN UNDOPED AND INDIUM-DOPED GAAS WAFERS BY SI AND SI+P ION-IMPLANTATION())

We have studied electrical properties and low-temperature photolumines cence of n(+)-layers produced by Si and Si+P ion implantation into und oped and indium-doped liquid encapsulated Czochralski (LEG) grown GaAs semi-insulating (SI) substrates. The effects of implant dosage are co nsidered. It is shown that when compared to Si-only implantation, the Si+P co-implantation leads to suppression of tile deep level defect fo rmation in the anion sublattice, increasing the donor activation effic iency and obtaining: a sharper concentration profile of implanted atom s in both types of substrates. An additional improvement in radiation defect annealing can be obtained using indium-doped GaAs matrix. Howev er, no extra enhancement in donor activation efficiency due to In-dopi ng was observed.