17 December 1998 Soft x-ray ellipsometer using transmission multilayer polarizers
Author Affiliations +
A soft X-ray ellipsometer using transmissive multilayer polarizers has been developed. It employs monochromatic 13-nm radiation from a synchrotron as a light source. Fifty free- standing pairs of semitransparent Mo/Si multilayers were used as a transmissive polarizer and as an analyzer. A fabricated polarizer functioned well both as a linear polarizer and as a phase retarder. It had a polarizance of 0.999 and a phase retardation of 90 degrees; and the relative transmittance was 0.785. Arranging two transmissive polarizers in the polarizer/compensator-sample-analyzer configuration enabled full control of the polarization of the probe beam. The modified polarization of light reflected from a sample was analyzed by the rotating-analyzer ellipsometry method. This system was applied to measurements on Silicon on insulator (SOI) substrates with an ultrathin superficial Si layer. We verified that there was a large change in the ellipsometric angles in the interference region. A soft X-ray ellipsometer is a very promising tool for thickness measurements on SOI substrates because of its high sensitivity to the thickness of the superficial Si layer and its insensitivity to the thickness of the buried SiO2 layer.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Tsuneyuki Haga, Yuichi Utsumi, Sei-ichi Itabashi, "Soft x-ray ellipsometer using transmission multilayer polarizers", Proc. SPIE 3443, X-Ray and Ultraviolet Spectroscopy and Polarimetry II, (17 December 1998); doi: 10.1117/12.333605; https://doi.org/10.1117/12.333605

Back to Top