Phase equilibria in the InNiAs system at 600°C

Phase equilibria are established in the InNiAs system at 600 °C using X-ray diffraction and electron probe microanalysis. An In-rich liquid phase, NiAs2 and NiAs are demonstrated to be in thermodynamic equilibrium with InAs. The most prominent feature of the system is a solution phase, denoted the ζ phase, which probably completely traverses the isotherm from the phase NiAs in the Ni-As binary system to the phase ζ in the In-Ni binary system. A ternary phase with the average composition Ni0.75In0.16As0.09 is found to exist in the In-Ni-As system as well. It crystallizes in the cubic BiF3 or Fe3Si (D03) structure, with the lattice parameter a = 0.58437 ± 8 nm. The results of the present investigation are compared with earlier studies of phase equilibria in the In-Ni-As system. The utility of In-Ni and Ni-As phases as thermodynamically stable contact materials to InAs is also discussed.