In the past, ULIS faced a major crisis which impacted the functionality of the big-runner products. The application JMP® was successfully used during the 3 main steps of crisis resolution, using the 8D methodology:
- - Problem description:
A confidence interval calculation was used in order to compare the failure rates by product.
The “power platform” was used in order to determine whether the defect was originally present or if it was caused by a process drift.
Custom Wafermaps were created in the “Graph builder platform” in order to locate the defect on silicon wafers. The graph builders’ user-friendly interface was also helpful in creating chronograms of batch process histories and in determining when the problem appeared.
- - Root cause analysis and Permanent Corrective Action:
By using JMP®‘s custom designer “distribution platform” and creating screening and response surface experiments, a gas rate variation was found to effect the failure rate.