A Simple Apparatus for the Determination of the Optical Constants and the Thickness of Absorbing Thin Films
- Authors: CALI', C; MOSCA, M; TARGIA, G
- Publication year: 2001
- Type: Articolo in rivista (Articolo in rivista)
- OA Link: http://hdl.handle.net/10447/45218
Abstract
We report on a simple and inexpensive apparatus useful for measuring the optical constants n, k and the thickness of weakly absorbing thin films. The measurement is based on an accurate determination of the reflectance and transmittance of a specimen illuminated by a laser beam. The laser beam is incident on a transparent substrate coated with the film to be evaluated, with an angle of incidence equal to the Brewster angle for the substrate, and its polarization can be switched between the p and s states. If the thickness is known to be within a presumptive range, measurements of the p and s reflectance and transmittance allow a calculation of the optical constants n, k and the thickness of the film, provided the absorption is weak.