Development and characterization of optoelectronic circuit boards produced by two-photon polymerization using a polysiloxane containing acrylate functional groups.

Research into the integration of optical interconnects in printed circuit boards (PCBs) is rapidly gaining interest due to the increase in data transfer speeds now required along with the need for miniaturized devices with increased complexity and functionality. We present a method that involves embedding optoelectronic components in a polymeric material and fabricating optical waveguides in one step. A silanol-terminated polysiloxane cross-linked with an acryloxy functional silane is utilized as a matrix material into which the 3D optical waveguides are inscribed by two-photon-induced polymerization. A pulsed femtosecond laser is used to directly write optical waveguides into the material, forming an optical link between lasers and photodiodes that are directly mounted on a specially designed PCB. The boards produced were characterized by monitoring the transmitted photocurrent as well as temperature-dependent data transmission properties. Data rates exceeding 4 Gbit/s were achieved.