Method for the metallization of optical fibers

Abstract

An improved method for providing high-quality optical fiber metallization with the required length at the required location. The method enables metallized optical fibers to be soldered and connected to mechanical components while reducing the level of stress in the metal coatings and providing strong adhesion, good conductivity and connectivity. The advantage of the method is a combination of vacuum evaporation and electroless deposition for the optical fiber metallization. A strong adhesion of the metal layer is achieved by the use of an evaporated thin metal layer, comprising an adhesion layer and a seed layer. The stress reduction is achieved due to electroless deposition, which is adequately thick for subsequent soldering/welding or other applications. The method comprises preparation for evaporation, preparation of optical fibers, evaporation of the thin metal adhesion and seed layer on the optical fiber, electroless deposition of an adequately thick metal layer, and acceptance testing. Metallization of optical fibers at any location across the fiber (patterned metallization) additionally includes application of an organic masking layer to the fiber before the metallization process, metallization of the fiber according to the present invention and subsequent dissolution of the masking layer. The inventive method applies to any fiber, in particular to SM (Single Mode) fibers and to PM (Polarization Maintaining) fibers.