Automated correlation of electrical failures to in-line inspections in a submicron semiconductor wafer fab

This paper summarises the status of work ongoing to correlate electrical failure sites in memory devices to in-line inspection data, with the ultimate objective of supporting yield improvement through the isolation of cause and effect mechanisms. The use of the KLA2130 and the Tencor SS7200 automatic systems has proved to be complimentary in linking in-line defectivity with electrical failures. The corresponding analysis approaches have different strengths and weaknesses: The KLA software provides important functionality, such as wafermaps, size distributions and pareto charts, but requires interactive use, whereas the analysis of Tencor data can be performed in batch mode, which can be advantageous in a data-rich environment