Vertical Optical and Electrical Interconnection for Chip-Scale-Packaged Si Photonic Transceivers

Three-dimensional optical and electrical I/O structures for chip-scale Si photonic optical transceivers have been developed. The optical I/O structure, which is called an “optical pin,” has a vertical polymer waveguide structure. The waveguide structure has 125- $\mu$ m-pitch 8°-tilted cores. The tilted cores were formed by oblique-illuminated exposure. The electrical I/O structure comprises 250- $\mu$ m-pitch regularly-arranged through-glass-vias. As these I/O structures are configured on the same side of the Si photonic module, the configuration enables simultaneous optical and electrical bonding to a polymer-waveguide-embedded printed circuit board. The developed I/O structures minimize the packaging area and support 25-Gbps multimode transmission.