Dr. Theodore Vorburger is a Guest Researcher in the Surface and Nanostructure Metrology Group in the Semiconductor and Dimensional Metrology Division at the National Institute of Standards and Technology. He was a Group Leader at NIST from 1987 until his retirement in 2009. This group is responsible for surface roughness and step height calibrations, which underpin the U.S. measurement system for surface finish, and for traceable linewidth measurements using critical dimension atomic force microscopes. He is a member of a project team that has developed standard bullets and cartridge cases for crime laboratories. Previously, Ted led the development of a calibrated atomic force microscope for calibrations of surface nano-scale length specimens, the development of atom-based step height standards for calibration of atomic force microscopes, and the development of a light scattering system for measuring surface roughness, and collaborated in the development of the world’s first sinusoidal-roughness Standard Reference Materials.
Surface finish is important to the function of industrial components ranging from extreme ultraviolet (EUV) mirrors to six lane highways. In this tutorial we emphasize the wide range of techniques that can be used to characterize surface finish. We first discuss the differences between the classes of methods—line profiling, area topography, and area-integrating. We particularly highlight the techniques of stylus profiling, optical profiling, scanned probe microscopy, and light scattering. We then discuss bandwidth limits for these techniques, which determine the ranges of spatial wavelengths that can be measured by each. Height resolution is another important limitation of instrument performance; however, for several types of instruments, the height resolution is at the atomic and subatomic levels. We also describe surface parameters and statistical functions, which are used to characterize the finish of engineering surfaces. Lastly, we discuss documentary standards developed to describe the instrument properties, the surface parameters, and the digital filters used to control the range of spatial wavelengths to be evaluated for different applications. Another recent development in standardization is the development of public websites for comparison of software calculations of surface parameters. These sites have been developed by NIST (http://pml.nist.gov/smats), the National Physical Laboratory, and Physikalische Technische Bundesanstalt, and their results have been compared with one another.
Session Date and Time
Tuesday, January 22, Afternoon (Half Day) 1:00pm - 5:00pm
Please mail/fax/email the completed registration form and payment to:
Dr. Chittaranjan Sahay (Director)