Method and apparatus for controlling the use of chemicals with expiration dates

摘要

A method and apparatus are provided for controlling the use of chemical materials in a semiconductor factory. The control is based upon the relationship among certain important dates relative to the useful life of the chemical materials used in the semiconductor manufacturing process. These dates include the current date and the expiration date, a critical date and a warning date for each chemical used on a particular assembly line. The expiration date is based upon a date beyond which the chemicals are not to be used in the semiconductor factory process. The critical date is usually no more than 3-4 days before the expiration date. Certain chemicals need more careful monitoring during this critical period. The warning date, usually a week before the expiration date, is used to alert the relevant engineering and production staff that a period of close attention on a particular production run is required. There are four major decision points in the method that is implemented by the apparatus.