Precipitation in Fe- or Ni-implanted and annealed GaAs

Abstract
We report the formation of metal/semiconductor composites by ion implantation of Fe and Ni into GaAs and a subsequent anneal to nucleate clusters. Electron diffraction experiments and high resolution transmission electron microscopy images indicate that these precipitates are probably hexagonal and metallic Fe3GaAs or Ni3GaAs with orientation relationship to GaAs of (101̄0)pp∥(422̄)m, (0002)pp∥(111̄)m, and [12̄10]pp∥[011]m. Correlation of the electrical and structural properties of the samples annealed at different temperatures shows that the buried Schottky-barrier model has general applicability.