Angle resolved optical metrology

There has been a substantial increase in the research and development of optical metrology techniques as applied to linewidth and overlay metrology for semiconductor manufacturing. Much of this activity has been in advancing scatterometry applications for metrology. In recent years we have been developing a related technique known as scatterfield optical microscopy, which combines elements of scatterometry and bright field imaging. In this paper we present the application of this technique to optical system alignment, calibration, and characterization for the purpose of accurate normalization of optical data, which can be compared with optical simulations involving only absolute measurement parameters. We show a series of experimental data from lines prepared using a focus exposure matrix on silicon and make comparisons between the experimental and theoretical results. The data show agreement on the nanometer scale using parametric simulation libraries and no "tunable" parameters.