Implantation and diffusion of $^{73}$As in GaAs and GaP

Self-diffusion on the As sublattice in intrinsic GaAs and foreign- atom diffusion on the P sublattice in intrinsic GaP were investigated in a direct way by As tracer diffusion measurements using the radioisotope /sup 73/As. For this purpose /sup 73/As was implanted in both materials at the ISOLDE facility of CERN. Then diffusion annealings were performed followed by serial sectioning and counting of the radioactivity in each section. The resulting profiles were simulated within a computer model which accounts for the observed loss of tracer to the diffusion ambient. The so-obtained diffusion coefficients for As in GaAs and GaP are compared with existing diffusivities in these compounds. (25 refs).