METHOD OF FORMING BALL BOND
A method of forming a ball bond ( 10 ) includes forming a bonding ball ( 12 ) at an end of a bonding wire ( 16 ). The bonding ball ( 12 ) is preformed to a substantially ball bond shape at a preform location ( 14 ) remote from a bonding site ( 24 ). The preformed bonding ball ( 22 ) is subsequently bonded to the bonding site ( 24 ).
1 . A method of forming a ball bond, comprising:
forming a bonding ball at an end of a bonding wire;
preforming the bonding ball to a substantially ball bond shape at a preform location remote from a bonding site; and
bonding the preformed bonding ball to the bonding site.
2 . The method of forming a ball bond according to claim 1 , wherein the perform location is adjacent to the bonding site.
3 . The method of forming a ball bond according to claim 1 , wherein the step of preforming comprises deforming the bonding ball against a first surface.
4 . The method of forming a ball bond according to claim 3 , wherein the bonding ball is deformed to a predetermined ball bond diameter.
5 . The method of forming a ball bond according to claim 3 , wherein the bonding ball is deformed to a predetermined ball bond height.
6 . The method of forming a ball bond according to claim 5 , wherein the bonding ball is deformed to a height of between about 10 μm and about 30 μm and a diameter of between about 40 microns (μm) and about 80 μm.
7 . The method of forming a ball bond according to claim 3 , wherein the first surface is contoured, the preformed bonding ball conforming to the first surface contour.
8 . The method of forming a ball bond according to claim 3 , wherein the first surface is of a harder material than the bonding wire.
9 . The method of forming a ball bond according to claim 1 , wherein after the preforming and before the bonding, the preformed bonding ball is removed from the preform location and moved to the bonding site.
10 . A method of forming a ball bond, comprising:
forming a bonding ball at an end of a bonding wire;
deforming the bonding ball against a first surface;
removing the deformed bonding ball from the first surface; and
bonding the deformed bonding ball to a second surface, wherein the second surface is adjacent to the first surface.
11 . The method of forming a ball bond according to claim 10 , wherein the bonding ball is deformed to a substantially ball bond shape.
12 . The method of forming a ball bond according to claim 10 , wherein the bonding ball is deformed to a predetermined ball bond diameter.
13 . The method of forming a ball bond according to claim 12 , wherein the bonding ball is deformed to a diameter of between about 40 microns (μm) and about 80 μm.
14 . The method of forming a ball bond according to claim 10 , wherein the bonding ball is deformed to a predetermined ball bond height.
15 . The method of forming a ball bond according to claim 14 , wherein the bonding ball is deformed to a height of between about 10 μm and about 30 μm.
16 . The method of forming a ball bond according to claim 10 , wherein after the removing and before the bonding, the preformed bonding ball is moved from the first surface to the second surface.
17 . The method of forming a ball bond according to claim 10 , wherein the first surface is of a harder material than the bonding wire.
18 . The method of forming a ball bond according to claim 10 , wherein the first and second surfaces are respectively surfaces of first and second connection pads on an integrated circuit (IC) die.
19 . A semiconductor package, comprising:
a die carrier having a plurality of bonding sites;
an integrated circuit (IC) die attached to the die carrier, the IC die having a plurality of first connection pads and a plurality of second connection pads, wherein indentation marks are formed on the first connection pads; and
a plurality of wires electrically connecting the bonding sites on the die carrier to the second connection pads on the IC die, wherein the wires include preformed ball bonds for the connections of the wires to the second connection pads.
20 . The semiconductor package of claim 19 , wherein the indentation marks on the first connection pads are of a substantially same shape as corresponding surfaces of the preformed ball bonds in contact with the second connection pads.