Meeting the Electrical, Optical, and Thermal Design Challenges of Photonic-Packaging

Integrated photonics is a promising route toward high-performance next-generation ICT and sensing devices. Although fiber-packaging is perhaps the most widely discussed obstacle to low-cost photonic devices, electronic-photonic integration and thermal-stabilization are also significant design considerations that need to be properly managed. Using a state-of-the-art Si-photonic optical-network-unit as a worked example, we illustrate some key challenges and solutions in the field of photonic-packaging. Specifically, we describe a novel solder-reflow bonding process for the face-to-face three-dimensional (3-D) integration of photonic and electronic integrated circuits, discuss current and future multichannel fiber-alignment techniques, and investigate the coefficient-of-performance of the thermo-electric cooler that stabilizes the temperature of the photonic components. The challenge of photonic-packaging is to simultaneously satisfy these electrical, optical, and thermal design requirements on small-footprint devices, while establishing a route to scalable commercial implementation.