Measurement setup, Measurement signal – Ocean Optics ElliCalc User Manual
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Ocean Optics Germany GmbH Thin Film Metrology
4
1.1
Measurement setup
A broadband white light source is focused on a thin layer under oblique incidence. The incoming light is
polarized by a “polarizer”, the reflected light is analyzed by an other polarizer, the so called “analyzer”. The
intensity as a function of wavelength is measured by a spectrometer, a PC extracts the wanted information.
1.2
Measurement signal
The typical modulated signal of such a spectroscopic thin film measurement might look like this (after some
data manipulations):
On the screen you see two different curves (Ψ/∆or tan(Ψ) and cos(∆) as a function of wavelength. ElliCalc
uses these signals to extract thicknesses and optical data for this (SiO
2
) layer on Si.
white light
source
polarizer
analyzer
spectrometer