Ball grid array package with stepped stiffener layer
View Patent ↗Electrically, thermally and mechanically enhanced ball grid array (BGA) packages are described. An IC die is mounted on a first surface of a stiffener. A first surface of a substrate is attached to a second surface of the stiffener that is opposed to the first surface of the stiffener. A bond pad of the IC die is coupled to a contact pad on the first surface of the substrate with a wire bond. The wire bond is coupled over a recessed step region in the first surface of the stiffener and through a through-pattern in the stiffener that has an edge adjacent to the recessed step region. The through-pattern in the stiffener is one of an opening through the stiffener, a recessed portion in an edge of the stiffener, or other through-pattern.
1. A ball grid array (BGA) package, comprising:
a stiffener that has
a first surface,
a second surface opposed to said first surface,
an opening through said stiffener that is open at said first surface and said second surface of said stiffener, and
a recessed step region in said first surface of said stiffener along an edge of said opening;
a substantially planar substrate that has a plurality of contact pads on a first surface of said substrate that are electrically connected through said substrate to a plurality of solder ball pads on a second surface of said substrate, wherein said second surface of said stiffener is attached to said first surface of said substrate; and
an IC die mounted to said first surface of said stiffener.
2. The package of claim 1 , wherein said edge is a closest edge of said opening to a central region of said first surface of said stiffener.
3. The stiffener of claim 1 , wherein said opening is substantially rectangular or trapezoidal shaped.
4. The stiffener of claim 1 , wherein said opening is irregular shaped.
5. The stiffener of claim 1 , wherein said recessed step region is substantially rectangular shaped.
6. The stiffener of claim 1 , wherein said recessed step region is substantially trapezoidal shaped.
7. The stiffener of claim 1 , wherein said recessed step region is irregular shaped.
8. The package of claim 1 , wherein said first surface and said second surface of said stiffener are substantially planar, and wherein said recessed step region has a surface that is substantially planar.
9. The package of claim 1 , further comprising:
a second opening through said stiffener that is open at said first surface and said second surface of said stiffener;
a second recessed step region in said first surface of said stiffener along an edge of said second opening.
10. The package of claim 1 , further comprising:
a plurality of openings through said stiffener that are open at said first surface and said second surface of said stiffener;
a plurality of recessed step regions in said first surface of said stiffener, wherein each of said plurality of recessed step regions is located along an edge of a corresponding opening of said plurality of openings.
11. The package of claim 1 , wherein said recessed step region is plated with an electrically conductive material.
12. The package of claim 1 , wherein an area of said first surface of said stiffener adjacent to said recessed step region is plated with an electrically conductive material.
13. The package of claim 11 , wherein said electrically conductive material includes at least one metal.
14. The package of claim 13 , wherein said at least one metal includes at least one of gold and silver.
15. The package of claim 1 , further comprising:
a wire bond that couples a bond pad of said IC die to a contact pad of said plurality of contact pads over said recessed step region and through said opening.
16. The package of claim 1 , further comprising:
a wire bond that couples a bond pad of said IC die to said recessed step region.
17. The package of claim 1 , further comprising:
a wire bond that couples a bond pad of said IC die to said first surface of said stiffener.
18. A ball grid array (BGA) package, comprising:
a stiffener that has
a first surface,
a second surface opposed to said first surface,
a recessed edge portion in an edge of said first surface and said second surface, and
a recessed step region in said first surface of said stiffener along said recessed edge portion;
a substantially planar substrate that has a plurality of contact pads on a first surface of said substrate that are electrically connected through said substrate to a plurality of solder ball pads on a second surface of said substrate, wherein said second surface of said stiffener is attached to said first surface of said substrate; and
an IC die mounted to said first surface of said stiffener.
19. The stiffener of claim 18 , wherein said recessed edge portion is substantially rectangular or trapezoidal shaped.
20. The stiffener of claim 18 , wherein said recessed edge portion is irregular shaped.
21. The stiffener of claim 18 , wherein said recessed step region is substantially rectangular shaped.
22. The stiffener of claim 18 , wherein said recessed step region is substantially trapezoidal shaped.
23. The stiffener of claim 18 , wherein said recessed step region is irregular shaped.
24. The package of claim 18 , wherein said first surface and said second surface of said stiffener are substantially planar, and wherein said recessed step region has a surface that is substantially planar.
25. The package of claim 18 , further comprising:
a second recessed edge portion in a second edge of said first surface and said second surface of said stiffener; and
a second recessed step region in said first surface of said stiffener along said second recessed edge portion.
26. The package of claim 18 , further comprising:
a plurality of recessed edge portions that each correspond to an edge of said first surface and said second surface of said stiffener; and
a plurality of recessed step regions in said first surface of said stiffener, wherein each of said plurality of recessed step regions is located along a corresponding recessed edge portion of said plurality of recessed edge portions.
27. The package of claim 18 , wherein said recessed step region is plated with an electrically conductive material.
28. The package of claim 18 , wherein an area of said first surface of said stiffener adjacent to said recessed step region is plated with an electrically conductive material.
29. The package of claim 27 , wherein said electrically conductive material includes at least one metal.
30. The package of claim 29 , wherein said at least one metal includes at least one of gold and silver.
31. The package of claim 18 , further comprising:
a wire bond that couples a bond pad of said IC die to a contact pad of said plurality of contact pads over said recessed step region and through said recessed edge portion.
32. The package of claim 18 , further comprising:
a wire bond that couples a bond pad of said IC die to said recessed step region.
33. The package of claim 18 , further comprising:
a wire bond that couples a bond pad of said IC die to said first surface of said stiffener.
34. A stiffener in a ball grid array (BGA) package, comprising:
a first surface;
a second surface opposed to said first surface;
a first opening through the stiffener that is open at said first surface and said second surface;
a first recessed step region in said first surface along an edge of said first opening;
a second opening through the stiffener that is open at said first surface and said second surface; and
a second recessed step region in said first surface along an edge of said second opening.
35. The stiffener of claim 34 , wherein said edge along said first opening is a closest edge of said first opening to a central region of said first surface of said stiffener.
36. The stiffener of claim 34 , wherein said first opening is substantially rectangular or trapezoidal shaped.
37. The stiffener of claim 34 , wherein said first opening is irregular shaped.
38. The stiffener of claim 34 , wherein said first recessed step region is substantially rectangular shaped.
39. The stiffener of claim 34 , wherein said first recessed step region is substantially trapezoidal shaped.
40. The stiffener of claim 34 , wherein said first recessed step region is irregular shaped.
41. The stiffener of claim 34 , wherein said first surface and said second surface are substantially planar, and wherein said first recessed step region has a surface that is substantially planar.
42. The stiffener of claim 34 , wherein said first recessed step region is plated with an electrically conductive material.
43. The stiffener of claim 42 , wherein said electrically conductive material includes at least one metal.
44. The stiffener of claim 43 , wherein said at least one metal includes at least one of gold and silver.
45. The stiffener of claim 34 , wherein an area of said first surface adjacent to said first recessed step region is plated with an electrically conductive material.
46. The stiffener of claim 34 , wherein said first recessed step region, an area of said first surface adjacent to said first recessed step region, and a surface area between said first recessed step region and said area of said first surface are plated with an electrically conductive material.
47. The stiffener of claim 34 , wherein the stiffener is a heat spreader.
48. The stiffener of claim 34 , wherein the stiffener comprises at least one metal.
49. The stiffener of claim 48 , wherein said at least one metal includes copper.
50. The stiffener of claim 48 , wherein said at least one metal includes aluminum.
51. The stiffener of claim 34 , wherein the stiffener comprises at least one of a ceramic, a dielectric material, an organic material, and a plastic.
52. The stiffener of claim 34 , wherein the stiffener is electrically conductive.
53. A stiffener in a ball grid array (BGA) package, comprising:
a first surface, having a central portion for mounting an IC die;
a second surface opposed to said first surface;
a first recessed edge portion in an outer edge of said first surface and said second surface;
a first recessed step region in said first surface along said first recessed edge portion;
a second recessed edge portion in an outer edge of said first surface and said second surface; and
a second recessed step region in said first surface along said second recessed edge portion.
54. The stiffener of claim 53 , wherein said first recessed edge portion is substantially rectangular or trapezoidal shaped.
55. The stiffener of claim 53 , wherein said first recessed edge portion is irregular shaped.
56. The stiffener of claim 53 , wherein said first recessed step region is substantially rectangular shaped.
57. The stiffener of claim 53 , wherein said first recessed step region is substantially trapezoidal shaped.
58. The stiffener of claim 53 , wherein said first recessed step region is irregular shaped.
59. The stiffener of claim 53 , wherein said first surface and said second surface are substantially planar, and wherein said first recessed step region has a surface that is substantially planar.
60. The stiffener of claim 53 , wherein said first recessed step region is plated with an electrically conductive material.
61. The stiffener of claim 53 , wherein an area of said first surface adjacent to said first recessed step region is plated with an electrically conductive material.
62. The stiffener of claim 61 , wherein said electrically conductive material includes at least one metal.
63. The stiffener of claim 62 , wherein said at least one metal includes at least one of gold and silver.
64. The stiffener of claim 53 , wherein the stiffener is a heat spreader.
65. The stiffener of claim 53 , wherein the stiffener comprises at least one metal.
66. The stiffener of claim 65 , wherein said at least one metal includes copper.
67. The stiffener of claim 65 , wherein said at least one metal includes aluminum.
68. The stiffener of claim 53 , wherein the stiffener comprises at least one of a ceramic, a dielectric material, an organic material, and a plastic.
69. The stiffener of claim 53 , wherein the stiffener is electrically conductive.
70. A stiffener in a ball grid array (BGA) package, comprising:
a first surface, having a central portion for mounting an IC die;
a second surface opposed to said first surface;
a plurality of openings through the stiffener that are open at said first surface and said second surface; and
a plurality of recessed step regions in said first surface, wherein each of said plurality of recessed step regions is located along an edge of a corresponding opening of said plurality of openings.
71. A stiffener in a ball grid array (BGA) package, comprising:
a first surface, having a central portion for mounting an IC die;
a second surface opposed to said first surface;
a plurality of recessed edge portions that each correspond to an outer edge of said first surface and said second surface; and
a plurality of recessed step regions in said first surface, wherein each of said plurality of recessed step regions is located along a corresponding recessed edge portion of said plurality of recessed edge portions.