Wire bonding over active circuits
View Patent ↗A semiconductor device includes a semiconductor die mounted over a package substrate. The die has a bond pad located thereover. A stud bump consisting substantially of a first metal is located on the bond pad. A wire consisting substantially of a different second metal is bonded to the stud bump.
1. A semiconductor device, comprising:
a semiconductor die mounted over a package substrate and having a bond pad located thereover;
a stud bump located on said bond pad, said stud bump consisting substantially of a first metal;
a first wire bonded to said stud bump, said first wire consisting substantially of a different second metal; and
a second wire bonded directly to a second bond pad located over said die.
2. The semiconductor device as recited in claim 1 , wherein said second metal is harder than said first metal.
3. The semiconductor device as recited in claim 1 , wherein said first metal is more malleable than said second metal.
4. The semiconductor device as recited in claim 1 , wherein said stud bump comprises gold.
5. The semiconductor device as recited in claim 1 , wherein said first wire comprises copper.
6. The semiconductor device as recited in claim 4 , wherein said stud bump further comprises palladium.
7. The semiconductor device as recited in claim 1 , further comprising a low-k dielectric layer or an active circuit under said bond pad.
8. A method of manufacturing a semiconductor device, comprising:
providing a semiconductor die over a package substrate, said die having a bond pad formed thereover;
forming a stud bump on said bond pad, said stud bump consisting substantially of a first metal;
bonding a first end of a bond wire to said stud bump, said wire consisting substantially of a different second metal;
bonding a second end of said bond wire to a bond site on said package substrate; and
doping said stud bump or said wire with a dopant selected to inhibit intermetallic formation between said stud bump and said wire.
9. The method as recited in claim 8 , wherein said first metal has a lower modulus than said second metal.
10. The method as recited in claim 8 , wherein said first metal is more malleable than said second metal.
11. The method as recited in claim 8 , wherein said stud bump is formed by a ball bonding process.
12. The method as recited in claim 8 , wherein said semiconductor die comprises a low-k dielectric under said bond pad.
13. The method as recited in claim 8 , wherein said stud bump comprises gold and said wire comprises copper.
14. A semiconductor device, comprising:
an integrated circuit package having a substrate;
a semiconductor die having first and second bond pads formed thereover and mounted over said substrate;
a gold stud bump bonded to said first bond pad;
a copper first wire connecting said gold stud bump and a bond site on said substrate; and
a second wire connected directly to said second bond pad.
15. The semiconductor device recited in claim 14 , wherein said gold stud bump is formed by a ball bonding process.
16. The semiconductor device recited in claim 14 , wherein said gold stud bump comprises palladium.
17. A semiconductor device, comprising:
a semiconductor die mounted over a package substrate and having a bond pad located thereover;
a stud bump located on said bond pad, said stud bump consisting substantially of a first metal;
a wire bonded to said stud bump, said wire consisting substantially of a different second metal; and
a low-k dielectric layer located between said bond pad and said semiconductor die.
18. A semiconductor device, comprising:
a semiconductor die mounted over a package substrate and having a bond pad located thereover;
a stud bump located on said bond pad, said stud bump consisting substantially of a first metal;
a wire bonded to said stud bump, said wire consisting substantially of a different second metal; and
an active circuit located between said bond pad and said semiconductor die.
19. A method of manufacturing a semiconductor device, comprising:
providing a semiconductor die over a package substrate, said die having a bond pad formed thereover;
forming a stud bump on said bond pad, said stud bump consisting substantially of a first metal;
forming a low-k dielectric layer between said bond pad and said semiconductor die;
bonding a first end of a bond wire to said stud bump, said bond wire consisting substantially of a different second metal; and
bonding a second end of said bond wire to a bond site on said package substrate.
20. A method of manufacturing a semiconductor device, comprising:
providing a semiconductor die over a package substrate, said die having a bond pad formed thereover;
forming a stud bump on said bond pad, said stud bump consisting substantially of a first metal;
forming an active circuit between said bond pad and said semiconductor die;
bonding a first end of a bond wire to said stud bump, said bond wire consisting substantially of a different second metal; and
bonding a second end of said bond wire to a bond site on said package substrate.