Methods and apparatus for wire bonding with wire length adjustment in an integrated circuit
An integrated circuit is wire bonded in a manner such that there is consistent RF performance from integrated circuit package to integrated circuit package. Bond distances within the integrated circuit are measured, each corresponding to a wire bond to be formed. An area under a hypothetical wire bond profile is calculated as a function of the bond distances, a baseline wire length, and a baseline loop height. A wire is bonded across a given one of the bond distances to form a given one of the wire bonds. A wire bond profile for the given wire bond is provided having an area thereunder that is substantially equal to the calculated area.
1. Apparatus for performing a wire-bonding operation in an integrated circuit, the apparatus comprising:
a memory; and
at least one processor, coupled to the memory, and operative to control the performance of the following operations: (i) measuring a plurality of bond distances within the integrated circuit, each bond distance corresponding to one of a plurality of wire bonds to be formed; (ii) calculating an area under a hypothetical wire bond profile as a function of the plurality of bond distances, a baseline wire length, and a baseline loop height; and (iii) bonding a wire across a given one of the plurality of bond distances to form a given one of the plurality of wire bonds; the bonding operation being configured to provide a wire bond profile for the given wire bond having an area thereunder that is substantially equal to the area calculated in the calculating operation.
2. The apparatus of claim 1 , wherein the calculating operation calculates the area under the hypothetical wire bond profile using an average of the plurality of bond distances.
3. The apparatus of claim 1 , wherein the area under the wire bond profile for the given wire bond is adjusted by adjusting a loop height of the given wire bond relative to the baseline loop height.
4. The apparatus of claim 1 , wherein the area under the wire bond profile for the given wire bond is adjusted by adjusting a wire length of the given wire bond relative to the baseline wire length.
5. The apparatus of claim 1 , wherein the calculating operation comprises calculating the area under the hypothetical wire bond profile using an integration technique.
6. The apparatus of claim 1 , wherein the bonding operation comprises calculating an area under a hypothetical wire bond profile for the given wire bond using the given bond distance, the baseline bond wire length, and the baseline loop height.
7. The apparatus of claim 6 , wherein the bonding operation comprises comparing the area under the hypothetical wire bond profile for the given wire bond to the area calculated as a function of the plurality of bond distances.
8. The apparatus of claim 1 , wherein the area under the wire bond profile for the given wire bond is adjusted in conjunction with the bonding operation if that area differs from the calculated area by more than a designated amount.
9. The apparatus of claim 1 , wherein the bonding operation is repeated for each of the plurality of wire bonds to be formed.
10. The apparatus of claim 1 , wherein the bonding operation comprises bonding the wire between a die of the integrated circuit and a capacitor of the integrated circuit.
11. The apparatus of claim 1 , wherein the bonding operation comprises bonding the wire between a capacitor of the integrated circuit and a lead of a package of the integrated circuit.
12. The apparatus of claim 1 , wherein the bonding operation comprises bonding the wire between a die of the integrated circuit and a lead of a package of the integrated circuit.
13. The apparatus of claim 1 , wherein the bonding operation comprises bonding the wire to a bond pad.
14. The apparatus of claim 1 , wherein the bonding operation comprises bonding the wire to a bond strip.
15. The apparatus of claim 1 , wherein the memory and processor are implemented in a computer.
16. The apparatus of claim 15 , further comprising a bonding tool coupled to the computer, and operative to perform the bonding operation.
17. A computer-readable storage medium having program code embodied therein for controlling the performance of a wire-bonding operation in an integrated circuit, wherein the program code when executed performs the steps of:
measuring a plurality of bond distances within the integrated circuit, each bond distance corresponding to one of a plurality of wire bonds to be formed;
calculating an area under a hypothetical wire bond profile as a function of the plurality of bond distances, a baseline wire length, and a baseline loop height; and
bonding a wire across a given one of the plurality of bond distances to form a given one of the plurality of wire bonds;
the bonding step being configured to provide a wire bond profile for the given wire bond having an area thereunder that is substantially equal to the calculated area.
18. The storage medium of claim 17 , wherein the calculating step calculates the area under the hypothetical wire bond profile using an average of the plurality of bond distances.
19. The storage medium of claim 17 , wherein the area under the wire bond profile for the given wire bond is adjusted by adjusting a loop height of the given wire bond relative to the baseline loop height.
20. The storage medium of claim 17 , wherein the area under the wire bond profile for the given wire bond is adjusted by adjusting a wire length of the given wire bond relative to the baseline wire length.