The Scanning Electron Microscope

The SEM at Kjemisk Insitutt at UiO is a SU8230 ultra-high resolution cold-field emission scanning electron microscope from Hitachi. It enables a great signal to noise ratio at low currents over a large range of accelerating voltages (from 0.1 to 30 kV). Therefore, also non-conductive materials can often be investigated. This can avoid sputtering of samples with a conductive material before investigations.

Besides secondary electron detection, a couple of more specific detectors and measurement modes are available. Examples are Low-angle and High-Angle Backscattering Electron Detectors and the STEM-Mode. This enables a great variety of possible applications and makes the SEM one of the key instruments in the Nanotechnology research in our groups.

  • Deceleration Mode

An advantage of the SU8230 SEM is the possibility to apply a negative voltage to the sample. This enables a deceleration of the primary electrons before they interact with the sample surface. A result of the reduced impact energy of the primary electron is a better surface sensitivity and less damage of fragile surface structures. This enables extraordinary imaging in the Nanometer scale.

  • EDX - EDS

An equipped EDX (also called EDS) detector enables the analysis of emitted X-rays. This leads to the chemical composition of the sample, of distinct selected surface regions and even a mapping of elements present in the sample.

The combination of SEM imaging and chemical analysis is important especially if the material composition of a surface on the nanometer scale is to be understood. Investigating solids, the high accuracy, easy handling and fast measurement make this method a competitive alternative to standard wet-chemical analysis methods.

The SEM is shared in between the Nanostructures and Functional Materials (NAFUMA) section and the Catalysis section of the UiO.


Related research groups: