摘要 |
A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser and photo detector are affixed to a planar substrate. A lens cap with a microlens is formed and affixed to the substrate with a seal. The lens cap forms a hermetically sealed cavity enclosing the laser and photo detector. Light from the laser is directed and shaped by the lens cap to couple into an external light guide. In an alternate method, the laser may be packaged using flip-chip assembly. A precision protrusion is also provided in the receptacle that fits into a photo-lithographically defined cavity in the substrate of the planar subpackage, thereby passively effecting and maintaining alignment of the axis of the microlens with respect to the central axis of the mating ferrule. The axial distance, in the direction of the laser beam, between the lens and the mating connector ferrule is controlled by the connector stop or front face of the MT ferrule. The axial distance between the lens and the mating connector ferrule may also be controlled by either the depth of the cavity or height of the protrusion. Alternatively, a protrusion that is photo-lithographically defined in the substrate of the subpackage could fit into a cavity in the receptacle or ferrule to passively effect and maintain alignment. |