Thin Film Characterization Using Rotating Polarizer Analyzer Ellipsometer with a Speed Ratio 1:3

Sofyan A. Taya, Taher M. El-Agez, Anas A. Alkanoo

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DOI: 10.4236/jemaa.2011.39056                

Abstract

In a recent previous work, we proposed a rotating polarizer-analyzer ellipsometer (RPAE) in which the two elements are rotating synchronously in the same direction with a speed ratio 1:3. We applied this technique to bulk samples. In this work, we present theoretically the characterization of 100 nm SiO₂ thin film using this spectroscopic RPAE. We assume a structure consisting of air (ambient)/SiO₂ (thin film)/c-Si (substrate). The ellipsometric parameters ψ and Δ are calculated when a clean signal is received by the detector and when a hypothetical noise is imposed on this signal. The film thickness and the optical constants of the film are calculated for the noisy signal in the spectrum range 200 - 800 nm. The results are compared with the proposed thickness and with the accepted values for SiO₂ optical constants.

Keywords

Ellipsometry, Rotating Polarizer-Analyzer Ellipsometer, Thin Film Characterization, Optical Constants, C-Si, SiO2

Conflicts of Interest

The authors declare no conflicts of interest.

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