Purpose The purpose of this paper is to provide an overview of the research in a project aimed at developing manufacturing techniques for integrated optical and electronic interconnect printed circuit boards (OPCB) including the motivation for this research, the progress, the achievements and the interactions between the partners. Design/methodology/approach Several polymer waveguide fabrication methods were developed including direct laser write, laser ablation and inkjet printing. Polymer formulations were developed to suit the fabrication methods. Computer‐aided design (CAD) tools were developed and waveguide layout design rules were established. The CAD tools were used to lay out a complex backplane interconnect pattern to meet practical demanding specifications for use in a system demonstrator. Findings Novel polymer formulations for polyacrylate enable faster writing times for laser direct write fabrication. Control of the fabrication parameters enables inkjet printing of polysiloxane waveguides. Several different laser systems can be used to form waveguide structures by ablation. Establishment of waveguide layout design rules from experimental measurements and modelling enables successful first time layout of complex interconnection patterns. Research limitations/implications The complexity and length of the waveguides in a complex backplane interconnect, beyond that achieved in this paper, is limited by the bend loss and by the propagation loss partially caused by waveguide sidewall roughness, so further research in these areas would be beneficial to give a wider range of applicability. Originality/value The paper gives an overview of advances in polymer formulation, fabrication methods and CAD tools, for manufacturing of complex hybrid‐integrated OPCBs.

An overview of the pound1.3 million EPSRC and company matched funded Innovative electronics Manufacturing Research Centre (IeMRC) Flagship project between 3 UK universities and 10 companies entitled ldquointegrated optical and electronic interconnect PCB manufacturingrdquo. The project aims to develop of optical waveguide design rules, layout software, fabrication methods compatible with commercial production, characterisation techniques and optical connector design to provide a supply chain for Polymer Multimode Optical Waveguide Printed Circuit Boards (OPCB) for 10 Gb/s board-to-board interconnections.

Purpose - To introduce the Innovative Electronics Manufacturing Research Centre Flagship Project: Integrated Optical and Electronic Interconnect PCB Manufacturing, its objectives, its consortium of three universities and ten companies and to describe the university research being carried out. This paper briefly reviews the motivation for developing novel polymer formulations, fabrication techniques, layout design rules and characterisation techniques for hybrid electronic and optical printed circuit boards (PCBs)using multimode polymer optical waveguide interconnects. Design/methodology/approach - The authors are investigating a number of different fabrication techniques which they compare with each other and with modelled calculations of waveguide components. The fabrication techniques include photolithography, laser ablation, direct laser writing, embossing, extrusion and ink jet printing.Findings - A number of design rules for polymer multimode waveguides have been found and published. Techniques for ink jetting polymer to print waveguides and laser ablation techniques have been developed. New formulations of polymer which cure faster for direct writing have also been developed.Research limitations/implications - Further work is needed to thicken the ink jet printed polymer and to investigate side wall roughness of the ablated waveguides and development of new polymer formulations for dry film. Further research is also needed on construction of prototype system demonstrators.Practical implications - The fabrication techniques being developed are designed to be transferred to industrial PCB manufacturers to enable them to make higher value optical PCBs. The design rules being discovered are being entered into commercial PCB layout software to aid designers of optical PCBs.Originality/value - The paper is of interest to PCB manufacturers who wish to upgrade their processes to be able to manufacture optical PCBs. The university research is original and some has been published as shown in the publications in the reference list.

In this paper we describe the direct laser writing of complex structures in a multifunctional acrylate polymer system using fan-out and grey-scale diffractive optical elements (DOE). The effective writing speed of waveguides was successfully increased using a fan-out DOE element. The DOEs to produce greyscale outputs (such as an intensity ramp) and other complex outputs (such as Heriot-Watt University logo) were used to fabricate greyscale and complex structures in polymer. Quantitative fabrication results of these structures are presented in this paper.