Scanning Electron Microscopy: Physics of Image Formation and Microanalysis, Second Edition

Scanning electron microscopy (SEM) is traditionally the Cinderella of electron microscopy, often seen as a playground for biologists and other disciplines remote from physics, and overshadowed by high resolution TEM, dominated by eminent scientists concerned with atomic structure and quantitative analysis. When Max Knoll in Berlin invented and constructed the first (crude) SEM in 1935 he did not bother to patent it. Some years later, von Borries and Ruska at Siemens und Halske Berlin, the first to realize high resolution electron microscopy in a commercial TEM, learned that Manfred von Ardenne in his private laboratory in Berlin had been given a contract by Siemens to develop an SEM. They immediately requested the management to cancel it as a waste of the Company's money, since the SEM `could never compete wth the TEM in image formation as the exposure time in serial scanning would be impossibly greater than in a comparable TEM image'! This view changed only when field emission guns became available. Many other difficulties were also overcome by advances in desk-top computing. Today the SEM is the microscope of choice in many areas of science and technology.