Patent ID: 9287185
Filing Date: 2016-03-15
CPC Classification: G01R,H01L

Claim Text:
1. A method comprising: testing a wafer comprising integrated circuit chips to produce test data; determining an original statistical variance of an original failure distribution using the test data; performing a process of creating a reconstructed failure distribution using sampling sizes of the test data that are less than all of the test data; determining a first statistical variance of the reconstructed failure distribution relative to sample size; determining a second statistical variance of a mean time to failure relative to sample size using the test data; combining the first statistical variance and the second statistical variance into a total reconstruction variance; determining whether the original statistical variance is less than the total reconstruction variance to identify whether additional wafers can be subjected to sample-based testing using the process of creating the reconstructed failure distribution with the sampling sizes; prohibiting the sample-based testing of the additional wafers based on the original statistical variance being less than the total reconstruction variance; and permitting the sample-based testing of the additional wafers based on the original statistical variance not being less than the total reconstruction variance.