GENERAL INFORMATION | STANDARD OPERATING PROCEDURE

The Woollam Variable-Angle Spectroscopic Ellipsometer (VASE) is an optical characterization instrument used to measure the thickness and optical properties of thin films and multilayer structures. Ellipsometry measures changes in light polarization upon reflection from a sample surface to determine film thickness, refractive index, extinction coefficient, and dielectric function as a function of wavelength. The VASE system allows continuous adjustment of the angle of incidence, enhancing the accuracy and reliability of extracted optical constants and enabling characterization of anisotropic materials. The system is equipped with a Si/InGaAs detector providing a spectral range from 190 to 2500 nm for comprehensive optical characterization from ultraviolet to near-infrared wavelengths. An alternate focusing attachment enables analysis with a spot size of approximately 200 microns for spatially resolved measurements. Advanced modeling software enables fitting of complex multilayer structures and extraction of material properties with sub-nanometer thickness resolution.

It is commonly used for characterizing thin films in semiconductors, photovoltaics, displays, optical coatings, and protective layers. Applications include process control and quality assurance in thin film deposition, determination of band gap and absorption properties, analysis of surface roughness and interface quality, characterization of transparent conductive oxides, and study of organic and polymeric films.

For more information please contact Dr. Luca Telesca.