Abstract

Wideband in-situ optical monitoring enables the on-line characterization of optical coatings. Such characterization is an important part of the deposition error compensation process.^1,2 In the case of bulk-like thin films and highly stable deposition processes it is possible to determine only one parameter, the current layer thickness, after the deposition of each layer.² In the case of porous thin films and less stable deposition processes a reliable determination of optical coating parameters is more difficult, and a search for several parameters may be required after each layer deposition. A direct determination of multiple parameters from a single spectral monitoring scan may result in the instability of the determination of optical coating parameters. For this reason, a special mathematical treatment is required to provide stability of the on-line characterization procedure.

© 1998 Optical Society of America