Packaging of VCSEL arrays for cost-effective interconnects at <10 meters

Packaging techniques for optically connecting cabinet to cabinet, board to board within a chassis, or chip to chip within an MCM are described. An integrated interconnect fabric connecting router modules distributed across several boards within a cabinet, or across more than one cabinet is being developed, which requires innovative packaging technologies. The project is developing a 2 Gigabyte link including (1) a transceiver incorporating VCSEL arrays, photodetector arrays and CMOS drive/receive circuitry, (2) a board-to-board waveguide connection consisting of fibers attached to a laminate which can be appliqued to the board, and (3) blind mate connectors for both board to backplane and board to fiber cable interfaces. In the area of chip to chip interconnects "smart pixel module" technology is being developed, i.e. a self-contained package which integrates (1) two dimensional arrays of silicon based processing, drive and receive circuitry, (2) two dimensional arrays of VCSELs and photodetectors, and (3) the passive optics required to condition and route the input and output optical beams. The active optoelectronic devices (VCSELs and photodetectors) are bump bonded directly to the silicon, with the passive lenses bended directly to the 2D assembly. The integration of the VCSELs, photodetectors and lenses will be carried out at wafer scale. In implementing interconnects for distances of 10 meters or less, the focus is upon reducing costs by increasing the levels of integration while still achieving high yields, utilizing low cost CMOS circuits wherever possible, developing reliable, robust, low power dissipation optoelectronic devices, and robust, scalable passive interconnection systems.