Patent ID: 7047469

Claim:
A method of wafer failure signature identification, the method comprising: (a) building up a failure signature database, recording a plurality of failure signature data, each failure signature data including a failure signature, a location field for the faulty dies, a failure mode, a position dependence information and a dependent signature, wherein the position dependence information indicating if the failure signature is related to the location of the faulty dies; (b) testing a selected wafer and generating a test result including the location and the failure mode of the selected wafer, wherein the wafer has a wafer number; and (c) generating a comparison result by comparing the failure mode of the test result with the failure mode of each failure signature data by an automatic comparing means, wherein the comparison result includes a hit or a miss, and when the comparison result is a hit, the comparison result further includes a hit ratio, the wafer number and the failure signature, wherein as the hit ratio of the failure signature data exceeds a predetermined value, the step of comparing the dependent signature of the failure signature database is skipped.