Direct Attach of Photonic Components on Substrates With Optical Interconnects

Direct attach of lasers and photodiodes on boards with optical interconnects can facilitate high-density packaging of high-speed optical components. For the technology demonstration, test chips are assembled by means of optical polymer pillars on substrates with embedded arrays of waveguides (WGs) and 45deg mirrors. The light couples vertically though the optical pillars enabling 1.5-dB reduction of the WG-to-chip coupling loss to 0.5dB. The insertion loss of the module tested is less than 2 dB and 10-Gb/s signal transmission through the module is demonstrated with bit-error rate <10^-12. Three-dimensional finite-element analysis provides results on the stress distribution in the displaced pillars of different shapes