PRODUCTION OF WAVEGUIDE ADDED WITH RARE EARTH ELEMENT

摘要

PURPOSE:To provide the smaller size, lower loss and multi function by adding a rare earth element with good controllability to a core waveguide which is the light propagating part of the glass waveguide having a planar structure. CONSTITUTION:A glass filter 3 for the core contg. the rare earth element is formed by using an electron beam vapor deposition device on a substrate 1 on which a buffer layer 2 having a low refractive index is formed. The substrate is thereafter heat-treated at a high temp. A metal 4 is then formed on the core glass film 3 by a sputtering device and thereafter, a photoresist film 5 is applied on the metal film 4 and is subjected to photolithography and dry etching to pattern the core glass film 3. The photoresist film 5 and the metal film 4 are removed and the entire part of the core glass waveguide 3 is coated with a clad film 6. The rare earth element is added with the good controllability into the core of the glass waveguide having the planar structure. Thus, the optical device having the small size, the low loss and the multi function is obtd.