Metal cap assembly for optical communications
A cap assembly for optical communications comprising a housing that includes a front side perpendicular from a bottom side, opposing parallel first and second sides perpendicular from the bottom side, and a back side disposed perpendicularly between the first side and the second side offset from respective ends of the first side and the second side opposite the front side. The back side includes an opening there-through and a three-sided ledge formed along an interior of the first side leg, an exterior of the back side, and an interior of the second side leg. The cap assembly further includes a window configured to contact the three-sided ledge of the back side, the glass panel covering the opening there-through and attached to the assembly via a solder pre-form.
1. A method of forming at least one window for attachment to a metal cap assembly, comprising:
coating each side of an associated wafer;
forming a pattern on one side of the associated wafer;
layering a metallization seal ring onto the coating of the one side of the associated wafer in accordance with the pattern formed thereon; and
dicing the wafer in accordance with the pattern to form the at least one window, wherein the pattern is formed around the perimeter of the at least one window.
2. The method according to claim 1 , wherein layering the metallization seal ring onto the coating of the one side of the associated wafer in accordance with the pattern formed thereon further comprises layering a seed layer, an intermediate layer and a top layer onto said pattern.
3. The method according to claim 2 , wherein the seed layer comprises chromium, the intermediate layer comprises nickel, and the top layer comprises gold.
4. The method according to claim 3 , wherein attachment of the at least one window to the cap assembly comprises forming a hermetic seal between the at least one window and a back side of a housing of the metal cap assembly using a first solder pre-form inserted therebetween, wherein the housing includes:
a back side of the housing, which includes an opening therethrough; and
a first and second side of the housing, which both extend past the back side of the housing,
wherein the at least one window is configured to contact the back side of the housing covering the opening, but does not extend past the first and second sides of the housing.