OPTICAL WAVE-GUIDE CHARACTERIZATION OF DIELECTRIC FILMS DEPOSITED BY REACTIVE LOW-VOLTAGE ION PLATING

We determine the quality of single films of various oxides, which are deposited on thermally oxidized silicon wafers by reactive low-voltage ion plating (RLVIP), by measuring their optical waveguide losses. We use a prism coupler for inserting the radiation of a wavelength-select able He-Ne laser into the waveguide and a CCD camera for imaging the l ight scattered from the surface of the films. The waveguide losses of the RLVIP films are typically of the order of 1 to 10 dB/cm. Some data obtained for TiO2 layers on thermally grown SiO2 and RLVIP SiO2 seem to confirm the presence of an absorbing boundary layer between RLVIP S iO2 and TiO2 that has been found in SiO2-TiO2 multilayers. The wavegui de measurements also reveal unusual index gradients in thick (approxim ately 10 mum) single layers Of Al2O3 derived from multimode effective index calculations.