Comparative study of dielectric coating materials for micro-cavity applications

We study the potential of common dielectric coating materials used for the fabrication of high reflectance mirrors in micro-cavity devices used in the visible region. We examine materials grown using E-beam and thermal evaporation and magnetron sputtering. The refractive indices and the extinction coefficients of the coatings were calculated from transmission and reflectance spectrophotometric data. The surface roughness of single layer coatings was measured using atomic force microscopy and the scatter of the thin film coatings was approximated from roughness measurements.