MACHINE VISION INSPECTION IN A FULLY AUTOMATED TEST LINE

摘要

The Linked Power Line at Siemens Semiconductor's Regensburg facility is used to manufacture TO-220 and TO-263 power devices. The test area of the Linked Power Line consists of trim and form, electrical test, mark, automatic visual inspection and final pack. This line features no human handling, fully automatic vision inspection for all customer critical defects, and automatic data logging by lot.rnThe vision system from Applied Intelligent Systems, Inc., uses three cameras and computer controlled LED lighting to inspect top, bottom,rnand lead sides of the part for defects in molding, lead forming, and handling. The vision system displays lot statistics and prints reports, with SECS/GEM communication to a cell controller in development.rnMachine vision inspection has resulted in faster feedback for process control. Control for molding has been improved from sampled manual SPC to 100% inspection of production volume with fast feedback to the process, which is on a different line. Feedback for trim and form is essentially real time. Process problems can be detected and corrected before leading to defective units and yields have improved for each process. The overall defect rate is now significantly lower than conventional lines at other Siemens facilities manufacturing the same types of parts. The paper explains how these benefits were achieved and some of the obstacles that must be overcome in integrated back-end manufacturing.