Managing factory risk to improve customer satisfaction

Due to one single event that scrapped over 900 wafers, an approach was developed to prevent this type of catastrophic scrap from reoccurring. This factory-wide approach considered the affects of (1) People, Process and Methods; (2) Facilities; (3) Gases, Chemicals and other Source components. It also evaluated each individual process in extreme detail. This approach focused on measurable outputs to maintain process control. By implementing this approach of assessing factory risk, in-line scrap decreased by 27% over a one year period of time. In the 19 months since this approach was initiated, there has not been one in-line event that scrapped more than 375 wafers. Scrap reduction was accomplished by many different methods including increasing the sample frequency between measurable outputs, measuring product wafers where appropriate, modifying procedures including training, upgrading the factory infrastructure, adding tool sensorization, and applying SPC correctly.