Testing process performance based on the yield: an application to the liquid-crystal display module

摘要

Process capability indices have been introduced to provide numerical measures on whether a manufacturing process is capable of reproducing items meeting the specifications predetermined by the product designers or the consumers. Process yield is one of the most common criteria used in the manufacturing industry for measuring process perfor- mance. The formula S_(pk) has been proposed to calculate the process yield for normal processes. The formula S_(pk) provides an exact measure on the process yield. Unfortunately, the statistical properties of the estimated S-circurnflex _(pk) are mathematically intractable. In this paper, we apply the bootstrap simulation method to construct the lower confidence bound of S_(pk). We then present a real-world application to the liquid-crystal display module process, to illustrate how we may apply the formula S_(pk) to actual data collected from the factories.