POLRRIZER RZIMUTH [deg]Fig. 1. (A) Function F(P) = a" 2 + 3I2 - 1 for two different PMpositions. (B) and (C) The same curves before correction (circles)and after correction of the Fourier coefficients for the polarization-dependent sensitivity and nonlinearity of the detection system
The correction coefficients may appear to be a func-tion of wavelength mainly through the PDS of thedetector. That is why when the ellipsometer is used asa spectroscopic instrument these coefficients must bemeasured at some different wavelengths in the spec-tral region of interest.
References1. P. Hauge and F. Dill, "Design and Operation of ETA, an Auto-
mated Ellipsometer," IBM J. Res. Dev. 12, 472 (1973).2. G. Candela and C. Deane, "An Ellipsometry System for High
Accuracy Metrology of Thin Films," Proc. Soc. Photo-Opt. In-strum. Eng. 480, 2 (1984).
3. S. Jasperson and S. Scrnatterly, "An Improved Method for HighReflectivity Ellipsometry Based on a New Polarization Modula-tion Technique," Rev. Sci. Instrum. 40, 761 (1969).
4. B. Drevillon et al., "Fast Polarization Modulated EllipsometerUsing a Microprocessor System for Digital Fourier Analysis,"Rev. Sci. Instrum. 53, 969 (1982).
5. D. Aspnes, "Precision Bounds to Ellipsometer Systems," Appl.Opt. 14, 1131 (1975).
6. P. Hauge, "Recent Developments in Instrumentation in Ellip-sometry," Surf. Sci. 96, 108 (1980).
7. W. Hunter, "Effects of Detector Nonlinearity on Calibrationand Data Reduction of Rotating-Analyzer Ellipsometers," J.Opt. Soc. Am. 66, 94 (1976).
8. D. Aspnes and A. Studna, "Methods for Drift Stabilization andPhotomultiplier Linearization for Photometric Ellipsometersand Polarimeters," Rev. Sci. Instrum. 49, 291 (1978).
9. R. Azzam and N. Bashara, Ellipsometry and Polarized Light(North-Holland, Amsterdam, 1977).
10. S. Russev, "Automated Ellipsometric Device," Bulg. J. Phys. 15,5 (1988).
Collected Papers On ton ResearchSome of the world's most advanced research on laser coolingand storage of atomic ions is performed at NIST's Boulder, Colo.,laboratories. A recent publication, Trapped Ions and LaserCooling 11 (NIST TN 1324), reproduces a number of papers of thisTime and Frequency Division research group and is a companionto an earlier collection of papers. Subjects covered includespectroscopy and frequency standards, quantum jumps, and non-neutral plasma studies. The publication is available from the Super-intendent of Documents, U.S. Government Printing Office,Washington, D.C. 20402. Order by stock number 003-003-02918-1for $ 10 prepaid.
15 April 1989 / Vol. 28, No. 8 / APPLIED OPTICS 1507
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