International Business Machines Corporation

Board of Regents of the University of Nebraska

J.a. Woollam Co.

Stephen P Ducharme

Blaine D Johs

John A Woollam

John Campbell Scott

Robert J Twieg

William E Moerner

Craig M Herzinger

Steven E Green

Hassanayn M El Hajj

Hassanayn Machlab El Hajj

Disclosed is a system and method for controlling polarization state determining parameters of a polarized beam of light in an ellipsometer or polarimeter and the like system, (eg. a modulation element ellipsometer system), so that they are in ranges wherein the sensitivity, (of a sample system characterizing PSI and DELTA value monitoring detector used to measure changes in said polarization state resulting from interaction with a 'composite sample system,' comprised of a sample system per se. and a beam polarization state determining variable retarder, to noise and measurement errors etc. therein), is reduced. The present invention allows determining sample system per se. characterizing PSI and DELTA values, from Composite Sample System characterizing PSI and DELTA values, by compensating for the presence of present invention components, (VR1) and/or VR2), added to an ellipsometer or polarimeter and the like system. The present invention also improves the ability of an ellipsometer or polarimeter and the like system fitted with present invention components (VR1) and/or (VR2) to provide usably accurate and precise sample system characterizing PSI and DELTA determining data values, wherein a sample system per se. investigating polarized beam of light is oriented at other than a Principal or Brewster Angle of Incidence thereto, the use of which Angle of Incidence would otherwise be difficult, if not impossible. Practice of the present invention also allows determination of the 'Handedness' of a polarized beam of light, and of sample system Jones or Mueller Matrix component values. As well, the present invention provides means for making system components (VR1) and/or (VR2) added to an ellipsometer or polarimeter and the like system, essentially end user transparent when desired, without removal thereof from said ellipsometer or polarimeter system.

System and method for improving data acquisition capability in

In an ellipsometer, a phase-modulated, polarized light beam is applied to a sample, electrical signals are obtained representing the orthogonal planes of polarization of the light after it has interacted with the sample and the constants of the sample are calculated from the two resulting electrical signals. The phase modulation is sufficiently small so that the calibration errors are negligible. For this purpose, the phase modulator, phase modulates the light within a range of no more than ten degrees peak to peak. The two electrical signals are expanded by Fourier analysis and the coefficients thereof utilized to calculate psi and delta.

Ellipsometer

The present invention relates to polymeric materials that exhibit an erasable photorefractive effect which can be fabricated into optical devices such as optical wave guides.

Photorefractive materials

In an ellipsometer, a phase-modulated, polarized light beam is applied to a sample, electrical signals are obtained representing the orthogonal planes of polarization of the light after it has interacted with the sample and the constants of the sample are calculated from the two resulting electrical signals. The phase modulation is sufficiently small so that the calibration errors are negligible. For this purpose, the phase modulator phase modulates the light within a range of no more than ten degrees modulations peak to peak. The two electrical signals are expanded by Fourier analysis and the coefficients thereof utilized to calculate psi and delta.

Small modulation ellipsometry

Growing community of inventors

Lincoln, NE, United States of America

Stephen P Ducharme