Smart in-line defectivity/metrology process control solution for advanced 3D integration

Abstract When combined with in-line local metrology, Automatic Visual Inspection/Classification is a powerful tool to characterize 3D interconnect processes, either at the R&D level or in volume manufacturing environments. A new methodology that uses visual inspection results to drive local smart metrology was used for the first time to control the fabrication process of micro-pillar/micro-bump vertical contacts. Quantification of the inspection time when the smart logic concept was used revealed a throughput increase of 23% on average, while consistency of the automatic morphological accuracy was preserved as confirmed by in-line mechanical profilometry. The morphology characterization is discussed with respect to the electrical performances at die level.