Lateral diffusion in Ni–GaAs couples investigated by transmission electron microscopy

Abstract
A method has been devised for preparing lateral Ni–GaAs diffusion couples for transmission electron microscopy investigations. By annealing diffusion couples in situ in a hot stage, the growth of a ternary phase has been observed in the microscope, and shows parabolic time dependence of the growth. In the temperature range of 200–300 °C, Ni is the predominant diffusing species in the ternary phase while Ga and As are essentially immobile. The experimental results are compared with previous investigations of the reactions of Ni thin films with bulk GaAs.