Palladium thin film contacts on p-type ZnSe: adjustment of electrical properties by reaction diffusion

Abstract The ternary system PdZnSe was investigated at 340°C. A complete isothermal phase diagram is given, containing a newly discovered ternary phase τ 2 of approximate composition Pd 62 Zn 32 Se 6 . The reaction diffusion between Pd and ZnSe was investigated at 340°C and the diffusion path is described. Thin film palladium contacts were annealed at 250°C for 1–30 min. Lowest contact resistivities were reproducibly obtained after 2 min annealing. The results are related to the study of the ternary PdZnSe phase equilibria and Pd/ZnSe bulk reaction diffusion. A complex contact metallurgy is responsible for the attainment of good ohmic contact properties.