160-Gb/s Bidirectional Parallel Optical Transceiver Module for Board-Level Interconnects Using a Single-Chip CMOS IC

We report here on the design, fabrication and high-speed performance of a novel parallel optical module with sixteen 10-Gb/s transmitter and receiver channels for a 160-Gb/s bidirectional aggregate data rate. The module utilizes a single-chip CMOS optical transceiver containing both transmitter and receiver circuits. 16-channel high-speed photodiode (PD) and VCSEL arrays are flip-chip attached to the low-power CMOS IC. The substrate emitting/illuminated VCSEL and PD arrays operate at 985 nm and include collimating lenses integrated into the backside of the substrate. The IC-OE assembly is then flip-chip attached to a high density organic package forming the transceiver optical module. The exclusive use of flip-chip packaging for both the IC-to-optoelectronic (OE) devices and for the IC-to-organic package minimizes the module footprint and associated packaging parasitics. The OE-on-IC assembly achieves a high area efficiency of 9.4 Gb/s/mm² (Schow et al., 2007). The complete organic carrier transceiver package provides a low-cost, low-profile module similar to a conventional chip-carrier that can be directly surface mounted to a circuit board using a conventional BGA solder process. SLC transceiver modules with transmitter and receiver OE-IC arrays were assembled and characterized. Operation of all 16 transmitters in the transceiver module was demonstrated at data rates >10 Gb/s. Similarly, all 16 receiver channels operated error-free at >10 Gb/s. The receiver eye-diagrams were generated using a second transceiver source and therefore constitute a full transceiver optical link.