1060-nm 28-Gb/s -Channel Modules Operated Over the Case Temperature Range

To reduce the power consumption of 4-channel 28-Gb/s miniature optical modules, a 4-channel double intra-cavity 1060-nm InGaAs/GaAs quantum-well vertical-cavity surface-emitting laser (VCSEL) array with 5-μm-wide apertures, a high differential gain, and a low temperature-insensitive differential resistance in conjunction with a specially optimized thermo-electric cooler heat sink for a reduced thermal resistance are used. Most important is the excellent resistance compatibility between the VCSEL and a low-power SiGe BiCMOS driver IC. Consequently, a 4-channel 28-Gb/s NRZ PRBS 2³¹ - 1 link operation at a bit error rate of 10-12 for an operational case temperature ranging from 25 °C to 70 °C was achieved at an unprecedentedly low VCSEL bias current of only 4 mA.