Parallel Optical Transmitter Module Using Angled Fibers and a V-Grooved Silicon Optical Bench for VCSEL Array

摘要

We propose an advanced structure of optical sub-assembly (OSA) for packaging of the vertical-cavity surface-emitting laser (VCSEL) array, using (111) facet mirror of the V-groove ends formed in a silicon optical bench (SiOB) and angled fiber apertures. The feature of our OSA can provide a low optical crosstalk between neighboring channels, a low feedback reflection, and a large misalignment tolerance along the V-groove. We describe the optimized design of fiber angle, VCSEL position, and fiber position. The fabricated OSA structure consists of 12 channels of angled fiber array, 54.7° V-grooves, Au-coated mirrors on (111) end facet of the V-grooves, and flip-chip-bonded VCSEL array on a SiOB. In this structure, the beam emitted from the VCSEL is deflected at the 54.7° mirror of (111) end facet and propagated into the angled fiber. The angled fiber array was polished by 57°. Fabricated OSAs showed a coupling efficiency of 30%-50% that is 25 times larger than that obtained from an OSA with a vertically flat fiber array. Our OSA showed large misalignment tolerance of about 90 μm along the longitudinal direction in the V-groove. We fabricated a parallel optical transmitter module using the OSA and demonstrated 12 channels ×2.5 Gb/s data transmission with a clear eye diagram.