Marco Asa, Andrea Scaccabarozzi
Description:Woollam VASE is a variable angle spectroscopic ellipsometer. Typical applications are the determination of the thickness and refractive index of thin films and coatings, the analysis of diffusion from surfaces, and the study of grating diffraction efficiency. The hardware is supported by a software, WVASE32, dedicated to the interpretation of the ellipsometric spectra, with access to a wide database of materials and models.
Working principleA complete description on ellipsometric techniques can be found at http://www.jawoollam.com/tutorial_1.html
- Measurements can be performed over the spectral range from 260nm to 1700nm, and over the incidence angle range from 15 to 90 degrees.
- Anisotropic and depolarizing samples can also be analyzed.
- Allowed sample sizes range from few millimiters to a 200 mm wafer.