Integrated circuit die for wire bonding and flip-chip mounting
An integrated circuit die carries conductive pads and thereon, the larger pads being suitable for flip-chip assembly and the smaller pads being suitable for wire bond assembly. The pitch between pads is at least the minimum required for flip-chip assembly, whereas the pitch between each of pads and the adjacent pad or pads is at least the minimum required for wire bond assembly. For wire bond assembly a passivation layer exposing all pads is provided, whereas for flip-chip assembly a passivation layer exposes only certain pads so that conductive bumps may be provided. The provision of pads complying with the minimum spacing requirements for both flip-chip and wire bond assembly enables a “dual purpose” (e.g. one set of pads being for normal production and another set for testing purposes) die to be produced without any increase in die size.
1. An integrated circuit die including first and second sets of conductive pads for enabling external connections to be made to the integrated circuit, there being at least a first predetermined center-to-center spacing between each pad of the first set and the adjacent pad or pads of the first set, and at least a second predetermined center-to-center spacing, less than said first spacing, between each pad of the second set and the adjacent pad or pads of the first and second sets, wherein the pads of the first set are disposed in two lines adjacent one or more edges of the die, the pads of the first set in one of the two lines being disposed in staggered relationship with respect to the pads of the first set in the other of the two lines, and a passivation layer exposing only pads of the first set, or exposing pads of the first and second sets.
2. A die as claimed in claim 1 wherein the pads of the second set are disposed in one of the two lines.
3. A die as claimed in claim 1 wherein the pads of the first set are larger in area than the pads of the second set.
4. A die as claimed in claim 3 wherein the area of each pad of the first set and the first predetermined center-to-center spacing are suitable for flip-chip assembly of the die, and the area of each pad of the second set and the second predetermined center-to-center spacing are suitable for wire bond assembly of the die.
5. A die as claimed in claim 1 wherein the pads of the second set are disposed in line adjacent one or more edges of the die.
6. A die as claimed in claim 1 wherein the pads of the second set are disposed in one of the two lines.
7. A die as claimed in any preceding claim wherein the first set of pads is connected to one set of connection points in the integrated circuit, and the second set of pads is connected to another set of connection points in the integrated circuit.