Post passivation interconnection schemes on top of the IC chips
View Patent ↗A new method is provided for the creation of interconnect lines. Fine line interconnects are provided in a first layer of dielectric overlying semiconductor circuits that have been created in or on the surface of a substrate. A layer of passivation is deposited over the layer of dielectric and a thick second layer of dielectric is created over the surface of the layer of passivation. Thick and wide post-passivation interconnect lines are created in the thick second layer of dielectric. The first layer of dielectric may also be eliminated, creating the wide thick passivation interconnect network on the surface of the layer of passivation that has been deposited over the surface of a substrate.
1. An integrated circuit chip comprising:
a silicon substrate;
an ESD circuit in or on said silicon substrate;
an internal circuit in or on said silicon substrate, wherein said internal circuit comprises a MOS device;
a dielectric layer over said silicon substrate;
a first metallization structure over said silicon substrate and in said dielectric layer, wherein said first metallization structure is connected to said ESD circuit;
a second metallization structure over said silicon substrate and in said dielectric layer, wherein said second metallization structure is connected to said internal circuit;
a passivation layer over said dielectric layer;
a first via in said passivation layer, wherein said first via is connected to said first metallization structure;
a second via in said passivation layer, wherein said second via is connected to said second metallization structure; and
a third metallization structure over said passivation layer, wherein said third metallization structure is connected to said first and second vias, wherein said ESD circuit is connected to said internal circuit through, in sequence, said first metallization structure, said first via, said third metallization structure, said second via and said second metallization structure, and wherein said third metallization structure comprises a metal line having a sheet resistance of smaller than 7 milliohms per square, said metal line comprising an adhesion/barrier layer, a seed layer on said adhesion/barrier layer and an electroplated metal layer on said seed layer, wherein the material of said electroplated metal layer is the same as that of said seed layer, wherein an undercut with an edge of said adhesion/barrier layer recessed from an edge of said electroplated metal layer is between 0.03 and 2 micrometers.
2. The integrated circuit chip of claim 1 , wherein said metal line has a thickness between 2 and 100 micrometers.
3. The integrated circuit chip of claim 1 , wherein said metal line has a width greater than 2 micrometers.
4. The integrated circuit chip of claim 1 , wherein said electroplated metal layer comprises electroplated gold.
5. The integrated circuit chip of claim 1 , wherein said passivation layer comprises a nitride layer having a thickness greater than 0.3 micrometers.
6. The integrated circuit chip of claim 1 , wherein said passivation layer comprises an oxide layer and a nitride layer over said oxide layer.
7. The integrated circuit chip component of claim 1 , wherein said adhesion/barrier layer comprises titanium.
8. An integrated circuit chip comprising:
a silicon substrate;
a driver, receiver or I/O circuit in or on said silicon substrate;
an internal circuit in or on said silicon substrate, wherein said internal circuit comprises a MOS device;
a first metallization structure over said silicon substrate and in said dielectric layer, wherein said first metallization structure is connected to a first node of said driver, receiver or I/O circuit;
a second metallization structure over said silicon substrate and in said dielectric layer, wherein said second metallization structure is connected to said internet circuit;
a passivation layer over said dielectric layer;
a first via in said passivation layer, wherein said first via is connected to said first metallization structure;
a second via in said passivation layer, wherein said second via is connected to said second metallization structure;
a third metallization structure over said passivation layer, wherein said third metallization structure is connected to said first and second vias, wherein said first node of said driver, receiver or I/O circuit is connected to said internal circuit through, in sequence, said first metallization structure, said first via, said third metallization structure, said second via and said second metallization structure, and wherein said third metallization structure comprises a metal line having a sheet resistance of smaller than 7 milliohms per square; and
a fourth metallization structure over said silicon substrate and in said dielectric layer, wherein said fourth metallization structure connects a second node of said driver, receiver or I/O circuit to an external circuit.
9. The integrated circuit chip of claim 8 , wherein said metal line has a thickness between 2 and 100 micrometers.
10. The integrated circuit chip of claim 8 , wherein said metal line has a width greater than 2 micrometers.
11. The integrated circuit chip component of claim 8 , wherein said metal line comprises electroplated gold.
12. The integrated circuit chip component of claim 8 , wherein said passivation layer comprises a nitride layer having a thickness greater than 0.3 micrometers.
13. The integrated circuit chip of claim 8 , wherein said passivation layer comprises an oxide layer and a nitride layer over said oxide layer.
14. The integrated circuit chip of claim 8 , wherein said metal line comprises a titanium-containing layer and a metal layer on said titanium-containing layer.
15. An integrated circuit chip comprising:
a silicon substrate;
a first internal circuit in or on said silicon substrate, wherein said first internal circuit comprises a MOS device;
a second internal circuit in or on said silicon substrate;
a dielectric layer over said silicon substrate;
a first metallization structure over said silicon substrate and in said dielectric layer, wherein said first metallization structure is connected to said first internal circuit;
a second metallization structure over said silicon substrate and in said dielectric layer, wherein said second metallization structure is connected to said second internal circuit;
a passivation layer over said dielectric layer, wherein said passivation layer comprises an oxide layer and a nitride layer over said oxide layer, wherein said passivation layer comprises an oxide layer and a nitride layer over said oxide layer, wherein said nitride layer has a thickness greater than 0.3 micrometers;
a first via in said passivation layer, wherein said first via is connected to said first metallization structure;
a second via in said passivation layer, wherein said second via is connected to said second metallization structure; and
a third metallization structure over said passivation layer, wherein said third metallization structure is connected to said first and second vias, wherein said first internal circuit has a signal node connected to said second internal circuit through, in sequence, said first metallization structure, said first via, said third metallization structure, said second via and said second metallization structure, and wherein said third metallization structure comprises a metal line having a sheet resistance of smaller than 7 milliohms per square, said metal line comprising an adhesion/barrier layer, a seed layer on said adhesion/barrier layer and an electroplated metal layer on said seed layer, wherein the material of said electroplated metal layer is the same as that of said seed layer, wherein an undercut with an edge of said adhesion/barrier layer recessed from an edge of said electroplated metal layer is between 0.03 and 2 micrometers.
16. The integrated circuit chip of claim 15 , wherein said metal line has a thickness between 2 and 100 micrometers.
17. The integrated circuit chip of claim 15 , wherein said metal line has a width greater than 2 micrometers.
18. The integrated circuit chip of claim 15 , wherein said electroplated metal layer comprises electroplated gold.
19. The integrated circuit chip of claim 15 , wherein said passivation layer comprises a nitride layer having a thickness greater than 0.3 micrometers.
20. The integrated circuit chip of claim 15 , wherein said passivation layer comprises an oxide layer and a nitride layer over said oxide layer.
21. The integrated circuit chip of claim 15 , wherein said adhesion/barrier layer comprises titanium.
22. The integrated circuit chip of claim 1 , wherein said electroplated metal layer comprises electroplated copper.
23. The integrated circuit chip of claim 1 , wherein said metal line further comprises a nickel layer on said electroplated metal layer.
24. The integrated circuit chip of claim 1 further comprising a polymer layer between said passivation layer and said third metallization structure.
25. The integrated circuit chip of claim 1 further comprising a polymer layer over said third metallization structure.
26. The integrated circuit chip of claim 8 , wherein said metal line comprises electroplated copper.
27. The integrated circuit chip of claim 8 , wherein said metal line comprises nickel.
28. The integrated circuit chip of claim 8 further comprising a polymer layer between said passivation layer and said third metallization structure.
29. The integrated circuit chip of claim 8 further comprising a polymer layer over said third metallization structure.
30. The integrated circuit chip of claim 15 , wherein said electroplated metal layer comprises electroplated copper.
31. The integrated circuit chip of claim 15 , wherein said metal line further comprises a nickel layer on said electroplated metal layer.
32. The integrated circuit chip of claim 15 further comprising a polymer layer between said passivation layer and said third metallization structure.
33. The integrated circuit chip of claim 15 further comprising a polymer layer over said third metallization structure.