Microstructure of Ge:Ta2O5 granular thin films: An application of TEM-tomography

Abstract

Microstructure of Ge: Ta2O5 granular thin films were observed by Transmission Electron Microscopy (TEM), Scanning Transmission Electron Microscopy with Energy Dispersive Spectrometer (STEM-EDS), and TEM with electron tomography. Three dimensional images Ge: Ta2O5 granular thin films were obtained from a tilt series of images, which were taken at regular tilt intervals. Some convex parts of irregular Ge granules, which overlapped by themselves or Ta2O5 in this thin film, have been well characterized to explain why there are many Moiré patterns in this Ge: Ta2O5 granular thin films. The result acquired by TEM with electron tomography shows Ge crystals have been grown up in a preferred orientation due to the confinement from the surrounding matrix. TEM with electron tomography can be used successfully to show the shapes of Ge particles distributed in the Ta2O5 network of this thin film, also the more detailed aspects of grown direction of this granular thin film. © 2007 The Japan Institute of Metals.