OPTICAL-CONSTANTS OF SPUTTER-DEPOSITED TI-CE OXIDE AND ZR-CE OXIDE-FILMS

Films of Ti oxide, Zr oxide, Ce oxide, Ti-Ce oxide, and Zr-Ce oxide we re made by means of reactive de magnetron sputtering in a multitarget arrangement. The films were characterized by x-ray diffraction and ele ctrochemical measurements, both techniques being firmly connected to s toichiometric information. The optical constants n and k were evalued from spectrophotometry and from variable-angle spectroscopic ellipsome try. The two analyses gave consistent results. It was found that n for the mixed-oxide films varied smoothly between the values for the pure oxides, whereas k in the band-gap range showed characteristic differe nces between Ti-Ce oxide and Zr-Ce oxide. It is speculated that this d ifference is associated with structural effects. (C) 1998 Optical Soci ety of America.