ADVANCED VACUUM-SYSTEMS FOR ANALYTICAL ELECTRON-MICROSCOPY

Recent technological advancements such as significantly improved power supply stability and polepiece design, as well as increased accelerating voltage all contribute to the primary objective of the scanning electron microscope (SEM): higher resolution. Similarly, the advent of analytical electron microscopy (AEM) has also expanded the scope of applications to include energy-dispersive spectrometry, wavelength-dispersive spectrometry, and electron probe analysis. Specimen contamination and damage has become increasingly problematic as SEMs are used as analytical instruments. In an effort to minimize contamination and etching, and thereby benefit from these advances, cleaner and more efficient vacuum systems are required. Such benefits were realized when, for the first time, a Cameca microprobe's diffusion pump was replaced by a low vibration cryogenic vacuum pump, resulting in faster pump down and lower ultimate vacuum pressures.