STUDY OF THE STRUCTURE AND PROPERTIES OF EPITAXIAL SILVER DEPOSITED BY ATOMIC-BEAM TECHNIQUES ON (001) INP

Epitaxial silver was deposited by molecular beam epitaxy on pre-thinned transmission electron microscopy (TEM) sample discs which were then rapidly transferred to a transmission electron microscope for full structure analysis. The TEM studies confirmed the epitaxial relation (011) Ag{norm of matrix}(001) InP indicated by reflection high energy electron diffraction investigations but showed in addition that films approximately 200 Å thick were composed of microdomains (200-400 Å in diameter) of mutually orthogonal orientation: [011] Ag{norm of matrix}[110] InP and [011] Ag{norm of matrix}[110] InP. One set of these domains progressively grew out as the film thickened, eventually leaving a single-domain film. It is possible that the microdomains originated from silver epitaxy on orthogonal domains of surface reconstruction. The TEM study also revealed a side effect of the InP surface cleaning treatment by argon ion bombardment and annealing-the presence of small indium metal islands due to differential sputtering of phosphorus from the InP surface. These are believed to be related to the abnormal electrical properties of the AgInP contacts, i.e. the greatly reduced Schottky barrier heights and the non-ideal log J-V characteristics. © 1979.