Die-up ball grid array package with enhanced stiffener
An electrically and thermally enhanced die-up tape substrate ball grid array (BGA) package and die-up plastic substrate BGA package are described. A substrate that has a first surface and a second surface is provided. The stiffener has a first surface and a second surface. The second stiffener surface is attached to the first substrate surface. An IC die has a first surface and a second surface. The first IC die surface is mounted to the first stiffener surface. A plurality of solder balls is attached to the second substrate surface. In one aspect, a heat spreader is mounted to the second IC die surface. In another aspect, the stiffener is coupled to ground to act as a ground plane. In another aspect, the substrate has a window opening that exposes a portion of the second stiffener surface. The exposed portion of the second stiffener surface is configured to be coupled to a printed circuit board (PCB). In another aspect, a metal ring is attached to the first stiffener surface. In another aspect, wire bond openings in the stiffener are bridged by one or more studs.
1. A ball grid array (BGA) package, comprising:
a substrate having an electrically insulating layer and a plurality of electrically conductive features formed on a first surface of said insulating layer, said substrate further having a substantially continuous planar electrically conductive layer on a second surface of said insulating layer;
a stiffener having a first surface attached to said first surface of said insulating layer;
an integrated circuit (IC) die having a first surface mounted to a second surface of said stiffener;
at least one electrically conductive via that extends through said substrate, and electrically couples an electrically conductive feature on from said first surface of said insulating layer to said electrically conductive layer on said second surface of said insulating layer; and
at least one wire bond that couples at least one bond pad on a second surface of said IC die to said electrically conductive feature, wherein said at least one wire bond extends through at least one opening through said stiffener that is open at said first and second surfaces of said stiffener.
2. The BGA package of claim 1 , wherein said at least one bond pad is coupled to a ground potential signal in said IC die, whereby said electrically conductive layer serves as a ground plane.
3. The BGA package of claim 1 , wherein said at least one bond pad is coupled to a power potential signal in said IC die, whereby said electrically conductive layer serves as a power plane.
4. The BGA package of claim 1 , wherein a portion of said electrically conductive layer is accessible as at least one solder ball pad.
5. The BGA package of claim 4 , further comprising:
at least one solder ball coupled to said at least one electrically conductive via.
6. The BGA package of claim 1 , further comprising:
a second at least one wire bond that couples a second at least one bond pad on said second surface of said IC die to at least one of said plurality of electrically conductive features on said first surface of said insulating layer, wherein said second at least one wire bond extends through said at least one opening through said stiffener.
7. The BGA package of claim 6 , wherein said plurality of electrically conductive features is electrically coupled through said substrate to a plurality of solder balls on said second surface of said insulating layer.
8. The BGA package of claim 1 , wherein said substrate is a tape substrate.
9. The BGA package of claim 1 , wherein said substrate is an organic substrate.
10. The BGA package of claim 1 , wherein said plurality of electrically conductive features include traces and contact pads.
11. The BGA package of claim 1 , wherein said electrically insulating layer includes polyimide tape.
12. The package of claim 1 , wherein said electrically conductive layer includes at least one metal.
13. The package of claim 12 , wherein said at least one metal includes copper.
14. The package of claim 12 , wherein said at least one metal includes aluminum.
15. The BGA package of claim 1 , further comprising:
an encapsulating material that encapsulates said IC die and said second surface of said stiffener.
16. The BGA package of claim 15 , wherein said encapsulating material includes one of a resin, a mold compound, and an epoxy.
17. The BGA package of claim 1 , further comprises:
a conductive material that fills said at least one electrically conductive via.
18. The BGA package of claim 17 , wherein said conductive material includes solder.
19. The BGA package of claim 1 , further comprising:
an array of thermally conductive vias that extend through said substrate from said first surface of said insulating layer to said second surface of said insulating layer, wherein said array of thermally conductive vias is coupled to said first surface of said stiffener; and
an array of solder balls, wherein each solder ball of said array of solder balls is coupled to said stiffener by a corresponding via of said array of thermally conductive vias.
20. The BGA package of claim 19 , wherein said stiffener, said array of thermally conductive vias, and said array of solder balls provide a thermally and electrically conductive path from said IC die to a printed circuit board (PCB) when the BGA package is mounted to the PCB.
21. The BGA package of claim 19 , wherein said array of thermally conductive vias is positioned within an area of said substrate to which said first surface of said IC die is attached.
22. The BGA package of claim 19 , wherein said stiffener is electrically conductive, and wherein the BGA package further comprises a second at least one wire bond that couples a second at least one bond pad on said second surface of said IC die to said second surface of said stiffener.
23. The BGA package of claim 22 , wherein said second at least one bond pad is coupled to a ground potential signal in said IC die, whereby said stiffener serves as a ground plane.
24. The BGA package of claim 23 , wherein said first at least one bond pad is coupled to said ground potential signal in said IC die, whereby said electrically conductive layer serves as a ground plane; and wherein said array of thermally conductive vias is coupled to said electrically conductive layer.
25. The BGA package of claim 23 , wherein said first at least one bond pad is coupled to a power potential signal in said IC die, whereby said electrically conductive layer serves as a power plane; and wherein said array of thermally conductive vias is electrically isolated from said electrically conductive layer.
26. The BGA package of claim 22 , wherein said second at least one bond pad is coupled to a power potential signal in said IC die, whereby said stiffener serves as a power plane.
27. The BGA package of claim 26 , wherein said at first least one bond pad is coupled to a ground potential signal in said IC die, whereby said electrically conductive layer serves as a ground plane; and wherein said array of thermally conductive vias is electrically isolated from said electrically conductive layer.
28. The BGA package of claim 26 , wherein said first at least one bond pad is coupled to said power potential signal in said IC die, whereby said electrically conductive layer serves as a power plane; and wherein said array of thermally conductive vias is coupled to said electrically conductive layer.
29. The BGA package of claim 26 , wherein said first at least one bond pad is coupled to a second power potential signal in said IC die, whereby said electrically conductive layer serves as a power plane of said second potential; and wherein said array of thermally conductive vias is electrically isolated from said electrically conductive layer.
30. The BGA package of claim 22 , wherein said stiffener is a substantially planar metal plate.
31. The BGA package of claim 30 , wherein said metal plate includes copper.
32. The BGA package of claim 30 , wherein said metal plate includes aluminum.