A Novel Method for Passive Digital Image Acquisition from a Scanning Electron Microscope

Abstract

The Center for Nanotechnology at NASA Ames Research Center is developing a microcolumn scanning electron microscope with energy-dispersive x-ray spectroscopy (MSEMS). The MSEMS has the potential for space explorations because it is lightweight, low power and has superior analytical capabilities, including imaging with submicrometer resolution and elemental analysis. The image acquisition software for the MSEMS is currently in its early stages of development. The development of the image acquisition software has lead to the research problem addressed in this thesis. The objective of this thesis is to provide a detailed explanation of a novel algorithm for obtaining digital images from a scanning electron microscope (SEM). An introduction to the SEM is presented including its theory of operation and current research. Established methods for digital image acquisition from an SEM are summarized, all of which exploit electron beam position. A new method for digital image acquisition is introduced, which disregards electron beam position. The hardware requirements for the new method are discussed. The model for the new method is fully developed. Manual and automated methods for determining the model parameters are explained. The automated methods are accomplished using correlation and edge detection. Some preliminary results are shown. Some advantages and disadvantages of the method are discussed and the future work is recommended. Possible further applications are speculated.