A PROJECTED-OUT DATE MANAGEMENT STRUCTURE IN A WAFER FAB

摘要

Projected-out date is the time that the fabrication of a lot is expected to be finished.rnProjected-out date management is a management (PDCA) process focused on the obtaining, evaluation,rnmodification, and release of a projected-out date. A projected-out date is not precise owing to manyrncauses including the inconsistency of human interventions, the emergence of hot lots, thernincompleteness of line-balancing worsened by line reentrancy, unexpected changes or fluctuations inrnproduction conditions, incomplete cycle time or stage cycle time statistics, and so on. The purpose ofrnthis study is to investigate these possible causes and to construct a whole structure of projected-outrndate management to aggregate and coordinate efforts and techniques in improving the accuracy of arnprojected-out date in a semiconductor fabrication plant. Based on this management structure, wernexpect that the overall efficiency and reliability of output projection in a fab can also be improved. Thernprojected-out date management structure is composed of four major parts: (1) projected-out daterndetermination; (2) projected-out date release; (3) projected-out date evaluation; (4) projected-out daternmodification.