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Kammrath & Weiss GmbH,
Schwerte, Germany
Carl Zeiss Industrielle Messtechnik GmbH,
Oberkochen, Germany
Scanning electron microscopes (SEMs) allow analysis
of sample surface morphology with nanometrescale
resolution. A typical application at IPP is the
investigation of plasma-exposed components. Material
scientists wish to inspect exactly the same spot – before and
after exposure. This requires that the components, such as a
divertor tile from the ASDEX Upgrade fusion research facility
or a component with soldered water connections be mounted
and traversed in the microscope. For this purpose, IPP acquired
an SEM from Zeiss with a custom high-load sample stage.
Furthermore, an integrated focused ion beam can be used to
prepare cross-sections on a micrometre scale.
The sample stage must position a divertor tile (230 x 105
square millimetres) with an accuracy of five micrometres, even
when tilted; the drift should be less than 100 nanometres over
five minutes. At a maximum load of ten kilograms, an image
resolution better than ten nanometres must be achieved. Other
specifications for the custom stage, which Kammrath & Weiss
GmbH manufactured on behalf of Zeiss, were a tilt range from
-15 to +70 degrees, rotation through 360 degrees, and a vertical
motion range of 100 millimetres.
A first class accessory
Heavy-duty stage for scanning electron microscope
No SEM manufacturer offers a standard stage that
can move a sample with a weight of ten kilograms and
a length of up to 230 millimetres under the electron
and ion beam to work in the micrometre or nanometre
range. High positional accuracy, low drift, and low
vibration – Kammrath & Weiss GmbH, experts for
special microscopy solutions, were challenged to meet
unprecedented requirements. “With the successful
implementation of the stage, we have gained a lot of
experience in the mechanical construction and the
control of the stage,” the company concludes. “For us,
it’s a reference project because we were able to show
what is possible with a standard SEM when we refine it
with our product.”
Photo: Kammrath & Weiss GmbH