Refractive Index of SiO_(2) Thin Films Deposited by Pulsed Laser Deposition with Silicone Targets for Fabricating Waveguide Devices

摘要

We deposited SiO_(2) films with different refractive indices by pulsed laser deposition with silicone targets. The deposition rate could control the refractive index of the films. The refractive index of the film deposited at 0.05 nm/pulse is greater than that of the film at 0.1 nm/pulse. The origin of the refractive index changes was to be film porosity changes, which was observed by surface profile meter. The deposited films were free of impurities such as OH and carbon. Thus, a 0.4-μm-thick SiO_(2) cladding film deposited at 0.1 nm/pulse was firstly formed on the whole surface of Si wafer, and then a 1-μm-thick SiO_(2) core film at 0.05 nm/pulse was fabricated in a line on the sample. Again, the sample was coated with a 0.1-μm-thick film at 0.1 nm/pulse. The sample functioned as an optical waveguide for a 633-nm line of He-Ne laser.