PLANAR AND WAFER LEVEL PACKAGING OF SEMICONDUCTOR LASERS AND PHOTO DETECTORS FOR TRANSMITTER OPTICAL SUB-ASSEMBLIES

摘要

A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser (310) and photo detector (320) are affixed to a planar substrate (302). The planar substrate (302) provides electrical connections to the components. A lens cap (330) with a microlens (332) is formed and affixed to the substrate (302) with a seal (338). The lens cap (330) forms a hermetically sealed cavity enclosing the laser (316) and photo detector (320). The inside surface of the lens cap (330) has a reflective coating (336) with a central opening over the emitting aperture of the laser (310). The central opening has an anti-reflective coating (337). Light from the laser (310) is directed and shaped by the lens cap (330) to couple into an external light guide (339). Residual light from the edge of the laser (310) reflects off the inside surface of the lens cap (330) and is incident upon the photo detector (320). In an alternate method, the laser (310) may be packaged using flip-chip assembly.