We present precise measurements of the refractive-index dispersion in the 0.6–1.5-μm range of dielectric films commonly used to form optical waveguides on Si. These are thermal SiO2 and phosphosilicate glasses formed from several types of low pressure chemical vapor deposition and Si3N4 formed by LPCVD. Mode refractive-index measurements were made with absolute accuracies of 1 × 10−4. We show that for samples ≳3 μm thick, the error in the film refractive index, determined by extrapolation of the mode refractive index data of the lowest two modes, is ≲1 × 10−4. Annealing studies of the phosphosilicate glass samples show that films containing 2% or more of P reached their equilibrium refractive indices after annealing at 800°C, while undoped silica films require annealing at 1100°C to reach equilibrium.
© 1988 Optical Society of America
Original Manuscript: May 9, 1988
Published: October 1, 1988
H. J. Lee, C. H. Henry, K. J. Orlowsky, R. F. Kazarinov, and T. Y. Kometani, "Refractive-index dispersion of phosphosilicate glass, thermal oxide, and silicon nitride films on silicon," Appl. Opt. 27, 4104-4109 (1988)