We proposed and demonstrated a new all-polymer based fabrication process for an all-polymer flexible and parallel
optical interconnect cable in which a vertical light coupler is integrated. The approach potentially cut down the cost by
eliminating a metallization process for alignment of multiple masks. Throughout the process we used a polyimide as the
substrate, coated by Epoclad as claddings, then AP2210B and WPR 5100 were used to fabricate waveguides and 45
degree mirror couplers, respectively. In addition, precisely aligned mirror couplers to waveguides are achieved by using
polymer-based, non-metallic, and transparent phase-based alignment marks. We tested a feature specific phase-based
alignment system. In addition, the shape and depth of the phase-based alignment marks are optimized for phase contrast
and Schlieren imaging. Our results shows that a contrast of the image is enhanced compared to that of observed by a
conventional imaging system. Such process enables to integrate polymer based waveguides by only using the polymer
based alignment marks on the WPR 5100 layer.
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