采用CONWIP投料系统的晶圆制造交货期设置方法

Due-Date Assignment for Wafer Fabrication Based on Constant Work-in-Process Release System

交货期设置是晶圆制造车间控制的重要任务之一。根据统计分析和排队理论提出3层结构交货期设置模型预测交货期。采用固定在制品(Constant WIP,CONWIP)投料保持系统在制品恒定和物料流程稳定,提出最大积聚未投放量法确定物料投放时间,采用基于模拟的等待时间分布估计等待时间。实例表明,该模型简单有效,提高了交货期预测的准确性。

Due-date assignment is an important task of shop floor control in wafer fabrication. A three-tier structure of due-date assignment model was constructed to forecast due-date by using the statistical analysis method and queuing theory. The CONWIP release policy was adopted to keep WIP fixed and the material flow stable. The Most Accumulating Unreleased Quantity method was proposed to confirm the release time for the different kinds of raw materials. A simulation-based wait time distribution was used to estimate wait time. Actual data were provided for demonstration of the mode, which proved that it is easy to use, and it significantly improves the accuracy of the forecast of due-date.