Optical 3D Profiler

Optical profilometry (OP) is a non-contact interferometric-based method for characterizing surface topography. A typical OP analysis provides 2D and 3D images of a surface, numerous roughness statistics, and feature dimensions.

Optical profiling uses the wave properties of light to compare the optical path difference between a test surface and a reference surface. Inside an optical interference profiler, a light beam is split, reflecting half the beam from a test material which is passed through the focal plane of a microscope objective and the other half of the split beam is reflected from the reference mirror. When the distance from the beam splitter to the reference mirror is the same distance as the beam splitter is from the test surface and the split beams are recombined, constructive and destructive interference occurs in the combined beam wherever the length of the light beams vary. This creates the light and dark bands known as interference fringes. Since the reference mirror is of a known flatness - that is, it is as close to perfect flatness as possible - the optical path differences are due to height variances in the test surface. This interference beam is focused into a digital camera, which sees the constructive interference areas as lighter and the destructive interference areas as darker. In the interference image each transition from light to dark represents one-half a wavelength of difference between the reference path and the test path. If the wavelength is known, it is possible to calculate height differences across a surface, in fractions of a wave. From these height differences, a surface measurement - a 3D surface map, if you will - is obtained.

Optical profilometry is suitable for numerous applications and sample types because it can accommodate many sample geometries, offering a wide range of possible analytical dimensions and a versatile Z-range, covering a broad range of potential surface roughness.

Technical specifications

Manufacturer: Filmetrics Inc.
Model: Profilm 3D

• PSI and VSI modes
• Vertical range: 0-3μm (PSI), 50nm-10mm (VSI)
• Stage size: 100x100mm automatic
• Vertical Resolution: 0.1nm (PSI), 1nm (VSI)
• Field size: 0.03mg to 15mg
• Manual X-Y stage 2.0x1.7mm (10x objective)
• Lateral resolution: 1μm

The Optical 3D Profiler has received funds from the CENanoTech project. In turn, the CENanoTech projectThe CENanoTech project (ref.: 2015 FEDER/S-16) is funded through the call for the development of R&D infrastructures launched by the Regional Ministry of Economy and Knowledge, of the Generalitat de Catalunya, with funding received from the European Regional Development Fund. The project has also been co-funded by the Severo Ochoa Programme granted by the Spanish Ministry of Economy, Industry and Competitiveness.