In scanning electron microscopy a thin, highly focused electron beam is scanned over the sample surface. The electrons interact with the sample and cause different reactions of the sample. Aside of electron back scattering and x-ray emission, which can be also used to map element specific distributions for each element on the surface, the sample emits secondary electrons which are detected synchronously to each beam position and which are used to create a microscopic image of the sample.
One characteristics of SEM is the enormous depth of focus. Magnifications from 15 – 150000 fold are commonly used in scanning electron microscopy.
The samples of interest must be either electrical conductive or have to be coated by a thin metallic layer to create conductivity..
With our scanning electron microscopes we offer you high resolution pictures of your sample surfaces.
For highest magnifications or non-conductive samples without the need of pre-coating with metals a special type of SEM, the FESEM, exists. Because of its origin (field emission) the scanned electron beam is much more precise and the probe current is much lower then in a normal SEM application. Therefore magnifications up to 300000 can be realized and isolating samples can be observed without prior coating.
SEM-picture of a porous surface
By using the wide spectra of modern analytical methods and the excellent equipment present at Limedion, we will find an answer to all of your questions. The following methods are present in our labs:
According to requirements we use further methods e.g., High temperature infra-red camera, Ulbrich sphere, adhesion tester and salt spray cabinet.