Tactile profilometry

At the Fraunhofer IST we use a Dektak XT profilometer from Bruker.
© Fraunhofer IST
At the Fraunhofer IST we use a Dektak XT profilometer from Bruker.

Characterization of surface topography by means of tactile profilometry

Using the stylus method, the surface is scanned along a line with a fine diamond tip and a height profile is recorded. A variety of surface morphological parameters can be determined from the height profile, e.g. roughness, undulation, the height histogram, skew and steepness of the height distribution, mean local surface slope, percentage contact area, etc.

Two devices with different resolutions

The Fraunhofer IST has two stylus instruments for the tactile profilometry at its disposal: the Dektak XT from Brucker (vertical resolution 0.5 nm, lateral resolution 0.2 or 1.25 µm) and the Talysurf from Taylor Hobson (vertical resolution 15 nm, lateral resolution 0.25 µm). Both devices can capture 3D as well as 2D scans. The Talysurf can also be used to characterize large components and complex geometries in terms of roughness and topography.

Determination of layer thickness by means of profilometry

Profilometric film thickness determination
© Fraunhofer IST

Tactile profilometry in practice: Layer thicknesses can be determined very quickly, easily and precisely by preparing a layer and using the profile.

4x4mm 3D surface scanning of a structured steel disk

4x4mm 3D-Oberflächenabtastung einer strukturierten Stahlscheibe
© Fraunhofer IST

It is also possible to determine the degree of roughness on large and heavy components

Rauheitsbestimmung an großen und schweren Bauteilen
© Fraunhofer IST