An interference fringe modulation skewing effect in white-light vertical scanning interferometry that can produce a batwings artifact in a step height measurement is described. The skewing occurs at a position on or close to the edge of a step in the sample under measurement when the step height is less than the coherence length of the light source used. A diffraction model is used to explain the effect.
© 2000 Optical Society of America
(120.6650) Instrumentation, measurement, and metrology : Surface measurements, figure
(120.6660) Instrumentation, measurement, and metrology : Surface measurements, roughness
(180.3170) Microscopy : Interference microscopy
Akiko Harasaki and James C. Wyant, "Fringe Modulation Skewing Effect in White-Light Vertical Scanning Interferometry," Appl. Opt. 39, 2101-2106 (2000)