Properties of a leaky quasi-waveguide formed by a thin film of refractive index smaller than the substrate are described. By exciting these leaky waves through the substrate, we have demonstrated a convenient and accurate method of measuring both the refractive index and thickness of thin films. Experimental results are given for polystyrene, with a demonstrated accuracy comparable with both that of prism coupling into a waveguiding film and with ellipsometry.
© 1983 Optical Society of America
Tie-Nan Ding and Elsa Garmire, "Measuring refractive index and thickness of thin films: a new technique," Appl. Opt. 22, 3177-3181 (1983)