Planar glass waveguides for high performance Electrical-Optical-Circuit-Boards (EOCB) -: The glass-layer-concept

In this paper a new concept for Electrical-Optical Circuit Boards (EOCB) using thin glass sheets with integrated multimode optical waveguides will be presented. The thin glass is promising an improvement of the thermal-mechanical behaviour of a PCB as well it provides suitable optical properties. Efforts were therefore begun to, develop a base material that can be laminated in between or on the outside with a thin layer of glass that in subsequent process steps can be structured providing optical waveguides to implement multimodal transmission of light. It will be shown that such glass layers can be handled by standard Iamination technology of the PCB fabrication process. This means, that planar glass waveguides can be incorporated into the circuit board package. Concerning the waveguide structuring several subconcepts are described with focus on ion exchange in molton salt. First experimental results are shown and discussed.