Comparing 3D optical microscopy techniques for metrology applications

In this application note, Bruker Nano discusses the metrology advantages of Bruker’s ContourGT^® 3D optical microscopes over confocal microscopes for certain applications. Key to these advantages is the ability to maintain subnanometer vertical resolution and 0.1 nanometer RMS repeatability, regardless of magnification or field of view.

3D optical microscopy is a mainstay metrology technology across a wide range of industries. There are a few techniques that provide a 3D surface representation from a microscope image, including the two key techniques of white light interferometry (WLI) and confocal microscopy, also known as laser scanning confocal microscopy (LSCM). These two methods are ubiquitous for measuring nanometers-to-millimeters surface heights. The principle of operation for each method provides different advantages and disadvantages.