Solder joint flip chip interconnection
View Patent ↗A flip chip interconnect has a tapering interconnect structure, and the area of contact of the interconnect structure with the site on the substrate metallization is less than the area of contact of the interconnect structure with the die pad. Also, a bond-on-lead or bond-on-narrow pad or bond on a small area of a contact pad interconnection includes such tapering flip chip interconnects. Also, methods for making the interconnect structure include providing a die having interconnect pads, providing a substrate having interconnect sites on a patterned conductive layer, providing a bump on a die pad, providing a fusible electrically conductive material either at the interconnect site or on the bump, mating the bump to the interconnect site, and heating to melt the fusible material.
1. A semiconductor device, comprising:
a substrate having a non-wettable surface;
a lead formed over the non-wettable surface with a portion of the lead forming a lead interconnect site having a width equal to a width of the lead;
a semiconductor die; and
a bump formed between the semiconductor die and lead interconnect site, the bump having a first profile with a first width across the lead interconnect site and a second profile having a length along the lead interconnect site greater than the first width.
2. The semiconductor device of claim 1 , wherein the bump includes a first region with a first melting temperature and a second region having a second melting temperature that is different from the first melting temperature of the first region.
3. The semiconductor device of claim 1 , wherein the first or second profile includes a tapered form that reduces stress on the semiconductor die.
4. The semiconductor device of claim 1 , further including a mask layer formed over the substrate with an opening over the lead interconnect site and over a portion of the substrate.
5. The semiconductor device of claim 1 , wherein the bump has a second width opposite the first width that is greater than the first width.
6. The semiconductor device of claim 1 , further including an underfill material deposited between the semiconductor die and substrate.
7. A method of making semiconductor device, comprising:
providing a substrate;
forming a lead over the substrate with a portion of the lead forming a lead interconnect site having a width equal to a width of the lead;
providing a semiconductor die; and
forming a bump between the semiconductor die and lead interconnect site, the bump including a first profile having a width across the lead interconnect site, and a second profile having a length along the lead interconnect site greater than the width.
8. The method of claim 7 , wherein the bump includes a first region with a first melting temperature and a second region having a second melting temperature that is different from the first melting temperature of the first region.
9. The method of claim 7 , wherein the bump has a collapsible region including eutectic solder, tin, silver, copper, or lead, and a non-collapsible region including lead solder, copper, gold, or nickel.
10. The method of claim 7 , wherein the lead has a width of 20-100 micrometers.
11. The method of claim 7 , further including depositing an underfill material between the semiconductor die and substrate.
12. The method of claim 7 , wherein the substrate is non-wettable.
13. The method of claim 7 , wherein the first or second profile includes a tapered form that reduces stress on the semiconductor die.
14. A semiconductor device, comprising:
a substrate;
a lead formed over the substrate;
a semiconductor die; and
a bump formed between the semiconductor die and lead, the bump including a first profile having a width across the lead and a second profile having a length along the lead different from the width.
15. The semiconductor device of claim 14 , wherein the first or second profiles includes a tapered form that reduces stress on the semiconductor die.
16. The semiconductor device of claim 14 , further including a mask layer formed over the substrate with an opening over the lead and over a portion of the substrate.
17. The semiconductor device of claim 14 , wherein the bump includes a first region with a first melting temperature and a second region having a second melting temperature that is different from the first melting temperature of the first region.
18. The semiconductor device of claim 14 , wherein the bump has a collapsible region including eutectic solder, tin, silver, copper, or lead, and a non-collapsible region including lead solder, copper, gold, or nickel.
19. The semiconductor device of claim 14 , further including an underfill material deposited between the semiconductor die and substrate.
20. A semiconductor device, comprising:
a substrate;
a lead formed over the substrate;
a semiconductor die; and
a bump formed between the semiconductor die and lead, the bump including a first profile having a width across the lead and a second profile having a length along the lead greater than the width.
21. The semiconductor device of claim 20 , wherein the substrate has a non-wettable surface.
22. The semiconductor device of claim 20 , wherein the bump includes a first region with a first melting temperature and a second region having a second melting temperature that is different from the first melting temperature of the first region.
23. The semiconductor device of claim 20 , wherein the bump has a collapsible region including eutectic solder, tin, silver, copper, or lead, and a non-collapsible region including lead solder, copper, gold, or nickel.
24. The semiconductor device of claim 20 , further including an underfill material deposited between the semiconductor die and substrate.
25. The semiconductor device of claim 20 , wherein the bump includes a tapered form that reduces stress on the semiconductor die.
26. A method of making semiconductor device, comprising:
providing a substrate including a conductive trace;
providing a semiconductor die; and
forming an interconnect structure between the semiconductor die and an interconnect site of the conductive trace with a length of the interconnect structure along the interconnect site greater than a width of the interconnect structure across the interconnect site.
27. The method of claim 26 , wherein the interconnect structure includes a bump.
28. The method of claim 26 , wherein the interconnect structure includes a tapered profile.
29. The method of claim 26 , wherein the interconnect structure includes a non-fusible portion and a fusible portion.
30. The method of claim 29 , wherein the non-fusible portion includes lead solder, copper, gold, or nickel.
31. The method of claim 29 , wherein the fusible portion includes eutectic solder, tin, silver, copper, or lead.
32. The method of claim 26 , wherein the conductive trace includes a width of 20-100 micrometers.
33. The method of claim 26 , further including depositing an underfill material between the semiconductor die and substrate.
34. A method of making semiconductor device, comprising:
providing a substrate including a conductive trace;
providing a semiconductor die; and
forming an interconnect structure between the semiconductor die and an interconnect site of the conductive trace with the interconnect structure elongated along a length of the conductive trace.
35. The method of claim 34 , wherein the interconnect structure includes a bump.
36. The method of claim 34 , wherein the interconnect structure includes a tapered profile.
37. The method of claim 34 , wherein the interconnect structure includes a non-fusible portion and a fusible portion.
38. The method of claim 37 , wherein the non-fusible portion includes lead solder, copper, gold, or nickel.
39. The method of claim 37 , wherein the fusible portion includes eutectic solder, tin, silver, copper, or lead.
40. The method of claim 34 , wherein the conductive trace includes a width of 20-100 micrometers.
41. The method of claim 34 , further including depositing an underfill material between the semiconductor die and substrate.
42. A semiconductor device, comprising:
a substrate including a conductive trace;
a semiconductor die; and
an interconnect structure formed between the semiconductor die and an interconnect site of the conductive trace with the interconnect structure elongated along a length of the conductive trace.
43. The semiconductor device of claim 42 , wherein the interconnect structure includes a bump.
44. The semiconductor device of claim 42 , wherein the interconnect structure includes a tapered profile.
45. The semiconductor device of claim 42 , wherein the interconnect structure includes a non-fusible portion and a fusible portion.
46. The semiconductor device of claim 45 , wherein the non-fusible portion includes lead solder, copper, gold, or nickel.
47. The semiconductor device of claim 45 , wherein the fusible portion includes eutectic solder, tin, silver, copper, or lead.
48. The semiconductor device of claim 42 , wherein the conductive trace includes a width of 20-100 micrometers.
49. The semiconductor device of claim 42 , further including an underfill material deposited between the semiconductor die and the substrate.