Temperature Coefficients of Refractive Indices of TiO₂-SiO₂ Films

We investigated the temperature coefficients of the refractive indices of TiO2-SiO2 films with different TiO2, concentrations at varying annealing temperature. We found that the temperature coefficients change from positive to negative in such films with a TiO2 concentration of more than 50 mol% in such a high-temperature annealing. We obtained a negative temperature coefficient of -4.7 x 10(-5) 1/degrees C for film with a TiO2 concentration of 74 mol%.