EVALUATION OF PRODUCTION DISPATCHING RULES THROUGH SCHEDULING SIMULATION IN THE FINAL TEST PROCESS OF LSI MANUFACTURING SYSTEM

Seven production dispatching rules in the real final test process of a one-chip microcomputer are evaluated through an event-driven simulation analysis with regard to the total number of processed lots, the number of tardy lots, the average turnaround time, and the cost per chip. The first rule is the well-known first-in first-out rule. The second is the rule intended to reduce the number of jig exchanges. The third is a rule that considers the allowable waiting time in station queues in addition to the second rule. A station includes a group of machines used for similar processing stages. The fourth rule considers the allowable flow time in the final test process in addition to the second rule. The fifth rule considers the remaining processing time of the machines in use in addition to the second rule. The sixth rule uses lot indication weighted by the waiting time in queue in addition to the second rule. The seventh and last rule considers the remaining processing time of the machines in use in addition to the sixth rule. By applying the simulation with dispatching rules to a real final test plan of 2086 lots per month, including 102 product types, it is shown that the seventh rule is superior to the others. © 1998 Scripta Technica. Electron Comm Jpn Pt 2, 80(6): 34–42, 1997