3D - Optical Surface Profilometer Laboratory

Objective
To measure the surface profile in order to quantify its roughness critical dimensions, such as step, curvature, and flatness, from the surface topography.
Equipment & Details
3D-Optical surface profilometerManufacturer- Bruker
Model- Contour GT
Year of Installation- 2014
Specifications |
|
Max. Scan Range |
Up to 10 mm |
RMS Repeatability (PSI) |
0.02 nm* |
Lateral Resolution |
0.38 μm min (Sparrow criterion); 0.26 μm (with AcuityXR®) |
Step Height Accuracy |
< 0.75%** |
Step Height Repeatability |
< 0.1% 1 sigma repeatability |
Max Scan Speed |
47 μm/sec (with standard camera) |
Sample Reflectivity |
0.05% - 100% |
Max. Sample Slope |
Up to 40° (shiny surfaces); Up to 87° (rough surfaces) |
Sample Height |
Up to 100 mm (4 in.) |
Sample Weight |
Up to 4.5 kg (10 lb) |
XY Sample Stage |
150 mm (6 in.) manual or automated option |
Tip/Tilt Function |
±6° manual in stage |
Optical Metrology Module |
Patented dual-LED illumination; Single-objective adapter; Optional automated or manual turret; Single or auto FOV lenses |
Objectives |
Parfocal: 2.5x, 5x, 10x, 20x, 50x, 115x LWD: 1.5x, 2x, 5x, 10x TTM: 2x, 5x, 10x, 20x Brightfield: 2.5x, 5x, 10x, 50x |
Available Zoom Lenses |
0.55x, 0.75x, 1x, 1.5x, 2x |
Camera |
Standard monochrome: 640 x 480 High-resolution monochrome (option): 1280 x 860 Standard color (option): 640 x 480 High-resolution color (option): 1280 x 860 |
Software System |
Vision64 Control and Analysis Software on Windows 7 64-bit OS |
Software Packages |
Production interface; Acuity XR; Annular Analysis; High Speed AF; Optical Analyses; Advanced Image |
XY Automation |
Manual stitching standard; Automated stitching, scatter and grid automation standard with motorized XY stage |
Calibration- |
Via traceable step standards |
System Footprint |
450 mm (W) x 534 mm (D) x 632 mm (H) |
System Weight |
60.3 kg (133 lb) |
Sample Details
Metallic, coated sample, thin films
Dimension: 10x10mm or larger
Preparation: No polishing is required
3D Surface contour of Electron beam welded pure niobium sample



Prof. Jyotsna Dutta Majumdar
Metallurgical & Materials Engineeringjyotsna@metal.iitkgp.ac.in
+91-3222-283288
Utility and Working Principle
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 (an "interferogram") below, 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 – 3D surface map, is obtained.