Investigation of thin films of high- and low-absorbing substances by the method of spectroellipsometry with excitation of surface polaritons

Abstract

The authors developed the methodology for optical property investigation of thin films of high and low absorbing substances on transparent and opaque substrates by means of spectroellipsometry with excitation of surface polaritons. For thin films of low absorbing substances on opaque substrates we used Beattie ellipsometric method with excitation of surface polaritons according to Otto scheme, and for the films of high absorbing substances on transparent substrates we used the same Beattie method with excitation of surface polaritons according to Kretschmann scheme. Measurements of ellipsometric parameters of several angles of incidence gave the possibility to use the solution of inverse ellipsometry task by means of electronic computer and to determine optical constants of thin films, their thicknesses, and optical constants of substrates in the case of high absorbing metal substrates. Obtained results of spectral relations of optical constants either for massive aluminum or for thin aluminum films gave us possibility to draw some interesting conclusions of their electron structure. In addition, they gave an opportunity to observe experimentally the separation of optical conductivity bands caused by electron transition in K and W points of Brillouin zone.