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The main technique used in the NSC project, "Building the hierarchical production planning system for the semiconductor fabrication" is the drum-buffer-rope (DBR) scheduling, developed from theory of constrains (TOC) philosophy. This research builds a hierarchical production planning and detailed schedule planning system. The system first based on the capacity requests of a long period (three months) to determine a schedule plan for the bottleneck resource. Then according to the bottleneck resources schedule, it constructs detailed schedule of critical resources and proceeds the capacity planning for non-critical resources for a short period. However, the performance of dispatching may influence the achievement of the detailed schedule planning. This thesis therefore aims at constructing a dispatching module for non-critical resources to accomplish the goal of detailed schedule. The machine types discussed in the non-critical resources dispatching module include general type, furnaces and implanters. The general types of machine have no specific characteristics while the furnaces and implanters have the batch process and group set-up time characteristics respectively. The adoptions of dispatching rules are as follows. The effect-emergency rule is applied to general types of machines to give the effect parts the higher priority to process. The minimum-emergency-cost rule is applied to furnaces to choose the best loading recipe and the best loading time. The DKFAM rule is adopted for implanters to determine the time switching to process another subfamily, while the effect-emergency rule is used to sequence the parts belong to a subfamily. The forecasting information about the wafer in the upstream and downstream workstations are provided while a dispatching rule is applied so as to make a correct dispatching decision. When using DBR scheduling concept, the buffer and the rod length plays an important role in the detailed scheduling stage. This length relates to the load of a factory and the loose of due dates. It also affects the performance of the dispatching model. This thesis also discusses the influence of the buffer and the rod length on the dispatching performance.
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