22 June 2013 Precision heterodyne ellipsometry with an improved conic fitting algorithm
Author Affiliations +
Proceedings Volume 8769, International Conference on Optics in Precision Engineering and Nanotechnology (icOPEN2013); 87692F (2013) https://doi.org/10.1117/12.2019043
Event: International Conference on Optics in Precision Engineering and Nanotechnology (icOPEN2013), 2013, Singapore, Singapore
Abstract
Ellipsometers based on heterodyne interferometers are inherently capable of precise measurements, with the ellipsometric angles determined from the amplitude and phase of a pair of quadrature signals. These signals are generally displayed as a Lissajous figure and the primary limitation to accuracy is determined by the goodness-of-fit to the ellipse, especially for ellipses with high ellipticity. In this paper we describe an improvement to the ellipse­ fitting algorithm of Halir & Flusser. A Michelson interferometer was constructed and a polarizer-quarterwave plate combination used to generate ellipses of moderate to extreme ellipticity. We show experimentally that our method yields excellent fits, even for axis ratios approaching 300: 1, yielding a one-sigma error of 0.5 mrad (less than λ/10000) in the presence of measurement noise.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lionel R. Watkins, Matthew J. Collett, "Precision heterodyne ellipsometry with an improved conic fitting algorithm", Proc. SPIE 8769, International Conference on Optics in Precision Engineering and Nanotechnology (icOPEN2013), 87692F (22 June 2013); doi: 10.1117/12.2019043; https://doi.org/10.1117/12.2019043
PROCEEDINGS
5 PAGES


SHARE
RELATED CONTENT

Phase shift via polarizer in an heterodyne interferometer
Proceedings of SPIE (October 24 2005)
Applications Of High Speed Pulsed-Laser Interferometry
Proceedings of SPIE (June 07 1989)
Integer Michelson Interferometer
Proceedings of SPIE (April 03 1989)
Phase shifting interferometric imaging ellipsometer
Proceedings of SPIE (October 03 1997)
Novel roll angular displacement amplifier
Proceedings of SPIE (May 30 2003)

Back to Top