A SILICON MICROBENCH CONCEPT FOR OPTOELECTRONIC PACKAGING

摘要

Optoelectronics (o/e) is currently too expensive for widespread application. The packaging (or fiber pigtailing) of o/e components may comprise up to 90% of the component's cost for some high performance components, and usually at least 50%. The development of an automated packaging system can greatly lower these packaging costs, enabling a host of new applications in areas of great economic and defense benefit to the US, including optical computer interconnects for advanced computing and ATM switch backplanes, advanced optical networks, and fiber optic gyros, to name just a few potentially high-impact applications.We believe that the pigtailing process must be automated to realize a significant reduction in the cost of o/e packages. We are addressing issues of automating the fiber pigtailing process on silicon waferboards or microbenches. This paper focuses on reflowing solders for the attachment of o/e components. We have recently developed miniature polysilicon heaters which are integrated on silicon microbenches. These miniature heaters avoid the problem of raising the entire microbench to the solder melting point to attach components. Most importantly, these miniature heaters are completely compatible with automating the attachment process.Designing silicon microbenches with on-board heaters requires some care. The thermal properties of the microbench itself along with all coatings on the surface and any heatsinking materials must be understood. The heaters must operate in a current and voltage regime compatible with the overall characteristics of the o/e package. Inadvertently reflowing solder in unanticipated locations may occur unless the thermal behavior of the microbench is thoroughly known. This paper describes the design and fabrication of our microbenches and an experimental and theoretical study we have performed on these silicon microbenches which gives us a complete picture of their thermal behavior.