October 26, 2017
Current Trends of Optical Metrology
An interview with Dr. Peter de Groot
Optical metrology providers are responding to customer demands for greater data density and ever more complex applications, often in difficult environments. AZoM spoke with Dr. Peter de Groot, of ZYGO, about his thoughts and expertise surrounding the subject and how he feels ZYGO will lead the industry moving forward.
AZO: Can you briefly describe ZYGO, the kinds of products that you sell, and the markets that you serve?
PdG: Sure! ZYGO was founded 50 years ago by Connecticut entrepreneurs as a provider of custom optics and precision engineering systems for optics fabrication. Metrology instruments for positioning and surface analysis became part of the business early in the development of the company, as a natural extension of the optics fabrication activity. Today about two thirds of what we sell falls into the metrology bucket, and the other third continues the tradition of state-of-the-art optics. Most of our metrology systems address high-precision needs in semiconductor lithography, consumer electronics, optical testing, precision manufacturing – generally, anywhere where high-performance dimensional metrology is key to process development and manufacturing yield.
AZO: What do you see as the major trends in optical metrology?
PdG: A major pull from the metrology market is for greater data density for ever more complex applications, often in difficult environments. A couple of examples illustrate the point. The smart phones that we carry with us everywhere have amazing camera lenses, made up of multiple aspheric elements. The manufacturing yield for the lens assembly depends not only on the shape of these complicated aspheres, but on the various built-in features that allow the individual lenses to fall into alignment when assembled in the lens barrel. Manufacturers want as much information as they can get about the surfaces and the interlocking alignment features, as quickly as possible, with high confidence. We have been addressing this need with the COMPASS™ system, which combines interference microscopy, multi-axis staging and entirely new software for evaluating lens molds as well as individual production lenses.
Another example is the testing of large flat optics, where there is an increasing emphasis on detailed full-field 3D imaging covering form, waviness and even surface roughness in one go. We recently introduced the Verifire™ HDX with an 11-megapixel camera and matching optics. This system may hold the world's record for data rate in a laser Fizeau interferometer – 250 million independent surface topography points per second, with a noise level of less than a nanometer. This kind of performance would have been difficult to imagine when I began my career the 1980's.
Click here to read the rest of this insightful article on the AZO Optics web site.
Zygo Corporation is a worldwide supplier of advanced optical metrology systems, high precision optical components, and complex electro-optical system design and manufacturing services.