Precise metrology and visualization of super-smooth surfaces (surfaces with roughness on the order of 1 nm, or less) can present several challenges. Optical instrumentation is most commonly used for these types of surfaces, due to their inherent non-contact technology. However, many optical technologies fall short in their capability to measure the surfaces with the accuracy, precision or repeatability necessary for adequate quality or process control.
One optical technology, Coherence Scanning Interferometry (CSI), offers clear advantages and superior performance on super-smooth surfaces compared to other 3D areal optical metrology techniques (i.e. confocal microscopy, focus variation). However, not all CSI-based instruments offer the same capabilities or level of performance. Interested to learn more? Read on...
ZYGO continues to excite the industry with market-leading innovation and performance. Our latest generation of 3D Optical Profiler products (NewView™ 9000; Nexview™ NX2) incorporate a slew of features designed to out-perform all others, while delivering the required performance that manufacturers of ultra-precision surfaces expect.
With Smart Setup, there's no guesswork or expert-level training required. Simply position your part and surface and click one button. The system automatically optimizes the various setup parameters, providing you with reliable data in less than one minute. What's more, it "sees" things you don't. Perfect for those super-smooth surfaces that lack discernable feature details. How's that for simple (and smart)?
This patented technique uses the best of CSI and the best of PSI to yield measurements with the highest level of precision and speed, with the lowest possible noise. Integrating automatic calibration and focus during scanning ensures that data is acquired at perfect focus – for each measurement. With SmartPSI, a series of surface measurements in rapid succession yield superior results on super-smooth surfaces, yielding results on the order of 0.06 nm Sq with 0.005 nm repeatability – in just seconds. And with more averaging, even smoother surfaces and better repeatability are achievable.
It's not enough to simply setup and acquire data – analyzing surface data should be smart and easy as well. One way that super-smooth surfaces are characterized is using the Power Spectral Density (PSD) Plot. PSD's are usually created from line profiles, which are easily extracted from a surface map in Mx™ Software. Line profiles, however, are sensitive to alignment and positioning – and if these are done incorrectly, the PSD can be misleading. With ZYGO's non-directional PSD analysis – a position-insensitive PSD is created for the entire map, making it simple to identify interesting surface structure.
If you would like to learn more or get in touch with us, please fill out the form below. We also have offices and demonstration equipment all over the place, so chances are we can easily arrange to see these capabilities in action – on your own parts!
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