Electron Microscope Observation of Au/Si (111) Interface in Atomic Level

Au/Si (111) interfaces were investigated by a high resolution electron microscope in both “cross-sectional” and “flat-on” modes. The epitaxially grown Au (111) films of 10–20 nm thick on Si (111) show a mosaic structure of about 100 nm in diameter making small angle grain boundaries. By the flat-on observation, a fringe contrast of 0.28 nm spacing are observed in the boundary. The cross-sectional observations reveal that the interface is flat and the intermixing layers are formed along the surface in Si side. A long periodicity contrast anomaly was often observed in the intermixing layer images.