PRODUCTION OF THIN GLASS FILM HAVING FUNCTIONABILITY

摘要

PURPOSE:To form an active element in a glass waveguide by immersing a porous thin glass film formed on a substrate into a soln., which is prepd. by dissolving a compd. constituting a functional material, then drying and sintering the compd., thereby forming the thin glass film added with the functional material. CONSTITUTION:The method (immersion method) of immersing the porous thin glass film deposited on the substrate into the liquid dispersed or dissolved with the functional material such as rare earth element and transition element for laser oscillation is used. This method makes use of the extremely high porosity and good air permeability which the porous body consisting of the fine glass particles formed by a vapor growth method using an oxyhydrogen flame possesses. The functional material can be added at a high concn. to the porous body consisting of the fine glass particles. The bulk density of the thin porous film consisting of the fine glass particles deposited on the substrate is preferably adjusted to a 0.2-1.3g/cm<3> range. The liquid contg. the functional material does not sufficiently infiltrate into the porous thin glass film if the bulk density is higher than said range. The porous thin glass film is cracked and is peeled from the substrate when said density is lower than the above-mentioned range.