We have obtained Er-doped ZnO thin film in a micropattern of reverse trapezoids processed on Si
substrate by sputtering and ultrafine polishing techniques. Near-infrared light emission was detected
successfully from the thin film filling a single micropit with 10 μm square. Transmission electron
microscopy (TEM) observation showed epitaxial growth of ZnO crystals along the curvature of the
micropit.