StraDex
Non-contact measurement of layer thicknesses during production processes and for quality assurance
Sensor types
StraDex sensor heads are used primarily for non-contact thickness measurement of single- or multilayer materials such as films, foils, coatings, or other (quasi)transparent materials such as silicon or glass. The sensors can function at two different optical wavelengths. Light of wavelength 1300 nm has the advantage that it can penetrate light-scattering layers. The alternative wavelength of 830 nm is available for especially thin layers (a few µm).
In the case of highly transparent materials with very smooth surfaces, such as glass or optical plastics, maximum thicknesses of up to 800 µm can be measured in-line during machining (such as grinding or polishing). The upper limit for the semiconductor material silicon is 350 µm – except for special applications.
In highly dynamic production environments, such as in blown film extrusion, it is possible to measure (multi)layers up to a total thickness of 300 µm. Under these production conditions it is also possible to determine the thickness of coatings (e.g. optical layers or adhesives) down to 5 µm with a precision of < 100 nm.
StraDex f24 has the greatest working distance of 24–44 mm. This sensor head is preferred for layer thickness measurements on wafer substrates. StraDex f2 focuses on 2–22 mm working distances and is used to determine layer or coating thicknesses in dynamic and possibly very rough production processes. StraDex p permits determination of thin layers as well as profilometry of the surface of an object. To this end, the spot of just 5 µm diameter is maintained at a constant distance of 8 mm from the autofocusing sensor window.
In contrast to the other sensors, StraDex a does not illuminate a spot but an area. This sensor was developed with the aim of measuring especially thin layers and or performing high resolution 3D topography over an area of < 1 mm2.
Sensor heads StraDex
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| Attachment | Size |
|---|---|
| StraDex_Produktlinie.pdf | 3.02 MB |