Quasi-hermetic photonic packages with polymer sealants in a central office environment

Full-hermetic package is ideal for protecting photonic device from adverse environment attacks. With increasing market pressure to lower the packaging and manufacturing cost of photonic components, designers are tuming more and more to new design approaches. In a controlled central office environment, a quasi-hermetic package may provide sufficient protection against moisture penetration. One of the challenges of hermetic packaging is to get light into, through, and uut of the package. Many new devices have fiber arrays comprised of multiple fiber ribbons transport through the metal wall. The creation of a hermetic seal at the point where multifiber arrays are transversing the package wall is particular challenging and expensive. The feasibility of an altemative fiber ribbon feed through seal based on polymer sealants is studied. Telcordia GR-1221-CORE and MIL-STD-883 specify that the upper limit of intemal moisture content is 5,000 ppm for hermetic packages. For a passive optical component used in a controlled central office environment, GR-122 1-GORE requires 500 hours of damp heat (75"C/90%RH or 85"C/85%RH) for qualification, and 2000 hours test data for information. The goal of a quasi-hermetic seal in this study is to keep the moisture content below 10,000 ppm after 1,000 hours of damp heat. A moisture sensor is imbedded in the package. The intemal moisture content is followed throughout the damp heat test. It's determined that for certain geometries quasi-hermeticity has been achieved.