Multiple-Beam Scanning Electron Microscopy

* anna-lena.eberle@zeiss.com Introduction When resolving structures at nanometer scale, electron microscopes are the tools of choice. Since the invention of the electron microscope, the technology has matured into a standard technique applied in a wide variety of disciplines and laboratories. To make a specific data set such as an SEM image recognizable to a human being, features in the data set must be sufficiently visible against the ubiquitous background of noise [18]. Because the analysis of large image data sets of several Terabytes or even Petabytes is difficult if not impossible for human beings, automated image processing by computers is required. [...]the maximum achievable scan speed of any conventional SEM is ultimately limited by the electron dose per pixel required to generate a desired minimal SNR at a given spot size. Because the current multi-beam setup has been optimized for a trade-off between cost and performance and has not been optimized for raw acquisition speed, these overhead times add to the scanning time, currently reducing the overall data rates by a factor of about two.