Abstract

We demonstrate a technique of applying the prism-coupler method to the characterization of dielectric films that are too thin to support enough guided modes in air for the normal application of the method. The technique is based on applying suitable index-matching liquids on the surface of the thin film to increase the number of effective indexes available for the determination of the refractive index and the thickness of the film. With this technique, even thin films that do not support any guided modes in air can be characterized. We apply the technique to the characterization of polymer thin films as thin as 100–200 nm and discuss its performance and limitation.

© 2007 IEEE

Birefringence measurements of thin dielectric films by the prism coupler method

Gervais Leclerc and Arthur Yelon
Appl. Opt. 23(16) 2760-2762 (1984)

Theory of Prism–Film Coupler and Thin-Film Light Guides

P. K. Tien and R. Ulrich
J. Opt. Soc. Am. 60(10) 1325-1337 (1970)

Birefringent prism couplers for thin-film optical waveguides

Irwin J. Kurland and Henry L. Bertoni
Appl. Opt. 17(7) 1030-1037 (1978)

Measurement of Thin Film Parameters with a Prism Coupler

R. Ulrich and R. Torge
Appl. Opt. 12(12) 2901-2908 (1973)

Determining the refractive index and thickness of thin films from prism coupler measurements

Steven T. Kirsch
Appl. Opt. 20(12) 2085-2089 (1981)