Optical based methodologies are the most popular ones for the characterization of transparent and semitransparent thin or thick films, offering non destructive and highly accurate measurements.

Film Characterization tools designed and developed by Thetametrisis are based on White Light Reflectance Spectroscopy (WLRS), a methodology that analyses the reflected interference spectrum from the sample, and offering real time measurements of film thickness, refractive index and absorption coefficients of thin and thick transparent or semitransparent films at very low cost compared to other techniques without compromise in accuracy and application range. Due to the particular design of the Thetametrisis tools, it is possible to extend their usage in various applications such as in liquids and in controlled (e.g. temperature and/or gas ambient) environments.

The implemented algorithms in FR-Monitor, the supplied software with every FR-tool, supports not only single film measurements over a reflective substrate, but also multilayer films stacks over a reflective substrate or even suspended single or multilayer films stacks.

In particular compared to Spectroscopic Ellipsometry (SE) the tools offered by Thetametrisis offer very high level of integration of the measurement set-up, high flexibility, state of the art software at a significantly lower cost. Furthermore, depend of the FR-tool configuration, typical absorbance/transmittance, fluoresces and reflectance measurements are supported.

A detail presentation of the principle of operation and the requirement experimental set-up of Absorbance/Transmittance, Fluoresce, Reflectance optical measurements, White Light Reflectance Spectroscopy methodology and Single Wavelengths Interferometry (a simplified approach of WLRS) are presented below:

Optical Measurements,
basic principles of Absorbance, Transmitance, Fluorescence
and Reflectance measurements.

Singe Wavelength Interferometry (SWI) measurements,
a very low cost technique for in situ monitoring of film thickness changes .

White light Reflectance Spectroscopy,
a low cost high accurate technique for film measurements it can be used
for both in situ & in vitro measurements.

Technologies Comparison,
advantages and disadvantages of presented Film Characterization techniques

Applications,
presentation of typical applications of the above described techniques.