Scanning electron microscope

• Imaging of surfaces by an electron beam scanning the specimen with a resolution of max. 1nm
• Conventional SEM observes specimens in vacuum. Samples are fixed and sputter-coated with gold. The coating back-scatters the electrons towards the detector
• Environmental SEM (ESEM) observes specimens in their natural state under low pressure. Electrons are scatterd by the gaseous film on the surface of the specimen