“CURING ” LOW YIELDS & RELIABILITY ISSUES IN PHOTONICS ASSEMBLY

The desire for high performance photonic components is often at odds with manufacturing process limitations and selection of compatible adhesive materials used in the fiber bonding process. Use of high performance adhesives, while desirable, typically requires longer curing times and higher temperature cure conditions to obtain the best results. Along with selection issues, low yields and reliability concerns are often attributed to adhesive performance and/or the process of curing the adhesive during assembly. Movement during post cure of adhesive joints leads to yield loss. Furthermore, reliability failures are reported highest during temperature cycling, due to improper bonding at the fiber interface. This paper provides an overview of application trials and dedicated development of a rapid curing technique that offers controlled, selective heating of the bond line. The use of microwave energy for curing polymeric adhesives in photonic component assembly has demonstrated cycle time reduction up to 10 to 20 times. Results of rapidly controlling the adhesive cure profile have shown process enhancement potential by minimizing or eliminating fiber joint movement during the adhesive cure cycle. In addition, the ability to selectively heat the bond line only and not the fiber cladding allows cure process temperatures compatible with full adhesive performance properties