OPTICAL-PROPERTIES OF PLASMA POLYMER-FILMS

The thickness and the refractive index of thin polymer films were meas ured in situ during plasma polymerization of hexamethyldisiloxane (HMD SO) by ellipsometry. The actual gas composition resulting from the pla sma chemical conversion of organic vapour was analysed by mass spectro metry. The gas composition influences both the deposition process and the film properties. The optical dispersion and transmittance of the d eposited films were characterized by spectroscopic ellipsometry (visib le range) and spectrometry (UV-visible-IR range) respectively. It was found that especially the refractive index can be varied over a wide r ange depending on the plasma conditions, and that films with graded re fractive index can be produced-