Warpage control stiffener ring package and fabrication method
View Patent ↗A warpage control stiffener ring package includes a substrate having an upper surface and corners. A segmented stiffener ring is formed of “L” shaped segments, each segment being mounted to the upper surface at a corner of the substrate, wherein a gap exists between each of the segments. By forming the segmented stiffener ring of segments having gaps therebetween, warpage of the segmented stiffener ring itself, and thus the thermal stress applied by the segmented stiffener ring on to the substrate, is reduced as compared to a continuous stiffener ring. This allows the segmented stiffener ring to be designed to minimize warpage of the warpage control stiffener ring package.
1. A structure comprising:
a substrate comprising:
a rectangular upper surface; and
corners;
a uniform thickness segmented stiffener ring comprising a plurality of segments, each segment of the plurality of segments coupled to the upper surface of the substrate at a respective corner of the substrate, wherein a gap exists between each segment of the plurality of segments.
2. The structure of claim 1 wherein a thermal coefficient of expansion of the segmented stiffener ring is greater than a thermal coefficient of expansion of the substrate.
3. The structure of claim 1 wherein each segment of the plurality of segments is L-shaped.
4. The structure of claim 1 wherein the segmented stiffener ring pulls the corners towards the segmented stiffener ring upon cooling.
5. The structure of claim 1 further comprising an integrated circuit chip coupled to the substrate.
6. The structure of claim 1 wherein each segment of the plurality of segments comprises a body at a respective corner of the substrate.
7. The structure of claim 6 wherein each segment of the plurality of segments further comprises a plurality of legs extending from the body.
8. The structure of claim 7 comprising a respective space on the upper surface of the substrate between each of the plurality of legs and a respective side of the substrate.
9. The structure of claim 7 wherein each segment further comprises a finger extending from a leg of the plurality of legs.
10. A structure comprising:
a substrate comprising:
an upper surface; and
corners;
a uniform thickness segmented stiffener ring comprising segments, each segment being coupled to the upper surface at a corner of the substrate, wherein a gap exists between each segment;
an electronic component coupled to the substrate; and
an inner stiffener ring between the segmented stiffener ring and the electronic component.
11. The structure of claim 10 wherein the inner stiffener ring is segmented.
12. The structure of claim 10 wherein the inner stiffener ring is continuous.
13. A structure comprising:
a substrate comprising:
a rectangular upper surface; and
corners;
a partially adhered continuous stiffener ring coupled to the upper surface, the partially adhered continuous stiffener ring comprising:
non-adherent corner portions at the corners of the substrate, the non-adherent corner portions being un-adhered to the upper surface of the substrate; and
adherent side portions adhered to the upper surface of the substrate.
14. The structure of claim 13 wherein the non-adherent corner portions are free to move relative to the upper surface.
15. The structure of claim 13 wherein the partially adhered continuous stiffener ring comprises a rectangular ring adjacent sides of the substrate.
16. The structure of claim 15 wherein the partially adhered continuous stiffener ring comprises corners and sides, the non-adherent corner portions comprising the corners of the partially adhered continuous stiffener ring and portions of the sides adjacent the corners of the partially adhered continuous stiffener ring.
17. The structure of claim 15 wherein the adherent side portions comprise center portions of the sides of the partially adhered continuous stiffener ring.
18. A structure comprising:
a substrate comprising:
an upper surface; and
corners;
a partially adhered continuous stiffener ring coupled to the upper surface, the partially adhered continuous stiffener ring comprising:
non-adherent corner portions at the corners, the non-adherent corner portions being un-adhered to the upper surface; and
adherent side portions adhered to the upper surface; and
a stiffener ring adhesive coupling the adherent side portions to the upper surface.
19. A structure comprising:
a substrate comprising:
an upper surface; and
corners;
a segmented stiffener ring comprising segments, each segment being coupled to the upper surface at a corner of the substrate, wherein a gap exists between each segment, the segmented stiffener ring varying in thickness along a length of the segmented stiffener ring.
20. The structure of claim 19 wherein the segmented stiffener ring is thickest at the corners of the substrate.
21. The structure of claim 20 wherein the segmented stiffener ring tapers to become thinner away from the corners of the substrate.
22. A structure comprising:
a substrate comprising:
an upper surface; and
corners;
a partially adhered continuous stiffener ring coupled to the upper surface, the partially adhered continuous stiffener ring comprising:
non-adherent corner portions at the corners, the non-adherent corner portions being un-adhered to the upper surface; and
adherent side portions adhered to the upper surface; and
a first cross member extending between a first of the adherent side portions and a second of the adherent side portions.
23. The structure of claim 22 , further comprising:
a second cross member extending between the first of the adherent side portions and the second of the adherent side portions; and
an electronic component coupled to the substrate between the first and second cross members.