Main Article Content
Desktop scanning electron microscopes (SEMs) are a relatively new product category. They are smaller, easier to use and faster than conventional SEM systems. However, their resolution is generally not as good. In order to reach ultra-high resolutions of three nanometers and below, the use of a high-voltage field emission gun (FEG) as the electron source is required. In 2018, Thermo Fisher Scientific succeeded, for the first time, in implementing a FEG into a commercial desktop SEM. Several challenges had to be overcome – such as reaching ultra-high vacuum levels within such a small system. The Thermo ScientificTM Phenom Pharos Desktop SEM now provides a resolution smaller than three nanometers, roughly three to five times better than most other desktop SEM models.