Laser Enhanced Direct Print Additive Manufacturing of Embedded Circular Cross-Section Optical Fiber Interconnects for Board Level Computing Devices

摘要： Integrated photonics have many compelling advantages for computing and communication applications, including in high-speed and extremely wide bandwidth operations. Current systems are typically hybrid assemblies of packaged photonic devices where printed circuit boards often serve to route electrical signals and power, and in some cases, have runs of optical fibers. We present a flexible, low cost assembly method of optical interconnects for photonic systems that could enable higher transmission rates, lower power requirements, improved signal integrity and timing, less heat generation, and improved security of communication signals. The new process is based on laser enhanced direct print additive manufacturing (LE-DPAM) that combines fused deposition modeling (FDM) of plastic, micro-dispensing of rubber-like materials, and picosecond laser subtraction. The process is demonstrated by fabricating few-mode and multi-mode optical fibers in a controlled manner such that compact, 3-dimensional optical interconnects can be printed along non-lineal paths. We have produced working optical interconnects with fiber core diameters from 70-μm to as small as 12-μm. Our results demonstrate surface roughness of less than 100 nm, and optical transmitted power of 63% that of a commercial fiber, for proof of concept devices. We anticipate these devices to be a starting point in the development of more sophisticated electro-optical computing devices using this new LE-DPAM technique. The LE-DPAM approach could lead to large scale integrated photonic computing devices that would replace our current generation of servers, computers, and phones.