COMPARISON OF CHEMICALLY INERT AND REACTIVE METAL COMPOUND-SEMICONDUCTOR INTERFACES - AUGA2 AND GOLD ON GASB(001)

AuGa//2-GaSb(001) and Au-GaSb(001) interfaces were prepared by molecular beam deposition and studied using Auger electron spectroscopy (AES), low energy electron diffraction (LEED), electron energy loss spectroscopy, scanning electron microscopy and X-ray microprobe analysis. AuGa//2 was chosen as an inert contact because it terminates a pseudobinary tie-line in the Au-Ga-Sb ternary phase diagram. An LEED-AES study of the annealing behavior of a gold film 40 A thick on GaSb(001) showed that gold reacts with GaSb even at room temperature. The resultant Au-Ga phase(s) in the film coalesce into islands above about 500 K. The chemical inertness of the AuGa//2 and the reactivity of the gold thin films are entirely consistent with the bulk thermodynamic properties of the Au-Ga-Sb system.