Flip-Chip Interconnection Technique for Beyond 100-Gb/s (4 × 25.8-Gb/s) EADFB Laser Array Transmitter

We developed a flip-chip interconnection technique that is suitable for an EADFB laser array transmitter operating at more than 100 Gb/s (4 × 25 Gb/s). The flip-chip interconnection technique provides a good thermal flow comparable to that of the conventional wire interconnection technique but with a higher modulation bandwidth and lower electrical crosstalk. For a flip-chip interconnection 112-Gb/s (4 × 27.9 Gb/s) module, the OTU4 mask margin is only 4% worse for simultaneous four-channel operation than for single-channel operation. For a flip-chip interconnection 400-Gb/s (8 × 50 Gb/s) module, we obtained clear eye openings for all eight lanes with simultaneous eight-channel operation.