Co-Packaged Optics (CPO) Technology Full Module Test Vehicle Demonstrations

We built co-packaged optics modules having polymer waveguide fiber interfaces successfully. We tested two types of assembly orders with Photonic-Integrated-Circuit (PIC) to Polymer Optical-Waveguides (PWG) first and PIC to PWG last. We characterized optical link performance before and after reflow, which indicated flip chip & BGA reflow compatibility. Full module build hardware underwent reliability pre-conditioning and then underwent JEDEC reliability stress testing, including (1) deep thermal cycling, (2) low-temperature storage, (3) high-temperature storage, and (4) high temperature and high humidity test followed by characterization. We evaluated the optical link loss of PIC to PWG to Ferrule assemblies using twelve channels per PIC with a 50-micrometer pitch at the PIC to PWG interface. Feasibility of further reduction of this pitch to less than 25 micrometers has been shown using modeling and prototype polymer waveguide hardware. This polymer optical waveguide method allows to support chip and optical waveguide bandwidth density up to 12 times larger compared to the case using standard v-groove single mode fiber interconnection.