System and method for identification of a reference integrated circuit for a pick-and-place equipment

1. A method of alignment of an integrated circuit chip pick-and-place equipment with an origin position of a wafer that supports these circuits, wherein at least one reference pattern formed on a reference chip during manufacture of the integrated circuits is optically searched on the wafer, the reference pattern being different from optically-recognizable patterns on other chips, and wherein the reference chip comprises geometric patterns that can be optically recognized in a passivation level or in a last metallization level of the wafer.

2. The method of claim 1 , wherein several reference chips are distributed in the wafer.

3. A system of integrated circuit assembly by means of a visual recognition pick-and-place equipment, comprising means for implementing the method of claim 1 .

4. An integrated circuit wafer, comprising at least one reference chip comprising in a passivation level or in a last metal level of the chip at least one optically-recognizable pattern, different from the patterns of the other chips formed in the wafer.

5. A method of aligning a wafer and a pick-and-place piece of equipment, the wafer including a plurality of integrated circuits formed on the wafer and the wafer further including a passivation layer and a metallization layer, and the method comprising:

forming a first optically recognizable reference pattern in the passivation layer or the metallization layer of at least one reference integrated circuit contained on the wafer; and

forming a second optically recognizable pattern on the integrated circuits other than each reference integrated circuit, the second optically recognizable pattern being different than the first optically recognizable reference pattern.

6. The method of claim 5 wherein each first optically recognizable reference pattern comprises a plurality of rectilinear parallel opaque patterns, a plurality of perpendicular opaque patterns adjacent the rectilinear parallel opaque patterns, and an opaque pattern surrounding the rectilinear parallel opaque patterns and the perpendicular opaque patterns.

7. The method of claim 1 further comprising creating an electronic file containing data regarding the location of each reference integrated circuit and data regarding which ones of the other integrated circuits are functional and/or defective.

8. The method of claim 7 further comprising:

sawing the wafer to separate the integrated circuits;

removing functional ones of the sawed integrated circuits and not removing during this operation the reference integrated circuits.

9. The method of claim 1 wherein some of the integrated circuits in the wafer are different sizes than other ones of the integrated circuits.

10. A wafer comprising a plurality of integrated circuits formed on the wafer, the wafer including a passivation layer and a metallization layer, and the wafer including at least one reference integrated circuit containing a first optically recognizable reference pattern formed in the passivation layer or the metallization layer, and at least some of the remaining integrated circuits containing a second optically recognizable pattern, the second optically recognizable pattern being different than the first optically recognizable reference pattern.

11. The wafer of claim 10 wherein each first optically recognizable reference pattern comprises a plurality of rectilinear parallel opaque patterns, a plurality of perpendicular opaque patterns adjacent the rectilinear parallel opaque patterns, and an opaque pattern surrounding the rectilinear parallel opaque patterns and the perpendicular opaque patterns.

12. The wafer of claim 10 wherein some of the integrated circuits in the wafer are different sizes than other ones of the integrated circuits.

13. An integrated circuit test system, comprising:

a plurality of wafers, each wafer including a plurality of integrated circuits formed on the wafer, the wafer including a passivation layer and a metallization layer, and the wafer including at least one reference integrated circuit containing a first optically recognizable reference pattern formed in the passivation layer or the metallization layer, and at least some of the remaining integrated circuits containing a second optically recognizable pattern, the second optically recognizable pattern being different than the first optically recognizable reference pattern;

a front end test station operable to test the wafers and to generate a file indicating which ones of the integrated circuits are functional and/or defective; and

a back end test station adapted to receive the tested wafers and a file from the front end work station, the back end test station operable to remove functional ones of the integrated circuits from the wafers using the file and the first optically recognizable reference pattern and the second optically recognizable pattern.

14. The integrated circuit test station of claim 13 wherein the file comprises an electronic file.

15. The integrated circuit test station of claim 14 wherein the file only indicates the locations of defective ones of the integrated circuits.

16. The integrated circuit test station of claim 13 wherein the back end test station is operable to saw the wafers as part of removing functional ones of the integrated circuits.

17. The integrated circuit test system of claim 16 wherein some of the integrated circuits are different sizes than other ones of the integrated circuits.

18. The integrated circuit test system of claim 13 wherein the first optically recognizable reference pattern includes a geometric pattern including a plurality of parallel opaque elements.

19. The method of claim 1 wherein each first geometric pattern comprises a plurality of rectilinear parallel opaque patterns, a plurality of perpendicular opaque patterns adjacent the rectilinear parallel opaque patterns, and an opaque pattern surrounding the rectilinear parallel opaque patterns and the perpendicular opaque patterns.

20. The method of claim 1 wherein some of the integrated circuits in the wafer are different sizes than other ones of the integrated circuits.