Study On The Spare Part Inventory Management Of The Semiconductor Wafer Fabrication

The Semiconductor Wafer Fabrication System (SWFS) is a very complex system with a variety of different kinds of equipment. Also, the production process is complicated. The spare parts are crucial to keep the SWFS running smoothly. The spare parts inventory management is necessary to reduce the production cost. Therefore, this research studies the effective methodology of spare parts inventory management in the industry of SWFS. There exist several problems in the current spare parts inventory management in the wafer fabrication industry: (1)lack of scientific spare parts classification method; (2)lack of the scientific and efficient spare parts demand forecasting method;(3)lack of a spare parts management information system. Based on the analysis of the situation of the wafer fabrication industry this research proposes some solutions for the spare part inventory management. The major contributions are as follows.Firstly, the classification is the fundamental issue of the spare parts inventory management. Based on the analysis of the current methods of parts classification used in the wafer fabrication industrial, a multi-dimensional classification method is proposed. This method is more accurate, effective in spare parts classification. Secondly, the demand forecasting is one of the important issues in the spare parts inventory management. The demand fluctuation influences the purchasing and inventory control to a great extent. Accurate forecasting is not only the assurance of safety and smooth production, but also very important in reducing the production cost and enhancing the customer service level. Because the demand of spare parts is always uncertain and fluctuating, it is very difficult to do the forecast accurately by traditional method. The gray prediction method is very powerful when handling nonlinear problems, and it only needs very few data and small samples. Therefore, this method is applied to build a model for the spare parts demand forecasting in the wafer fabrication company, in order to improve the forecasting efficiency and enhance the competitive ability of the company.Thirdly, the management information system is also important and a necessary support for the spare parts management. A complete solution of the spare parts management information system for the wafer fabrication company is proposed. The system can be used to improve the current management procedure, and solve some management issues like the optimization of the quota of part, quality control and supply chain management etc. The validity and pertinent of the system is proved by a case study in the wafer fabrication company.