An account of the early history of scanning electron microscopy has been presented by McMullan. Although Max Knoll produced a photo with a 50 mm object-field-width showing … See more

SEM samples have to be small enough to fit on the specimen stage, and may need special preparation to increase their electrical conductivity … See more

In a typical SEM, an electron beam is thermionically emitted from an electron gun fitted with a tungsten filament cathode. Tungsten is … See more

Backscattered electrons (BSE) consist of high-energy electrons originating in the electron beam, that are reflected or back-scattered out of the … See more

The signals used by a SEM to produce an image result from interactions of the electron beam with atoms at various depths within the sample. Various types of signals are produced … See more

The most common imaging mode collects low-energy (<50 eV) secondary electrons that are ejected from conduction or valence bands of the specimen atoms by inelastic scattering interactions with beam electrons. Due to their low energy, these electrons originate … See more

The nature of the SEM's probe, energetic electrons, makes it uniquely suited to examining the optical and electronic properties of semiconductor materials. The high-energy electrons from the SEM beam will inject charge carriers into the semiconductor. … See more