Development of infrared spectroscopic ellipsometer by synchronous rotation of the polarizer and analyzer

A type of infrared spectroscopic ellipsometer was designed and constructed to study the optical properties of materials in the 2.5-12.5μm wavelength range. The incident angle was continuously variable between 20° and 90°. The system operations, including data acquisition and reduction, preamplifier gain control, incident angle, wavelength setting and scanning were fully and automatically controlled by a computer. The reflectivity of Au and refractive index of GaAs bulk material, measured by the infrared ellipsometer, were given as an example, and a comparison of the results with other methods was also given. The experimental skill and main system errors were discussed.