Convenient Ratio Approach for Industrial Implementation in Estimating and Testing Process Yield

In recent years, since portable devices with thin and light designs are essential, the applications of the thin-film transistor liquid crystal display (TFT-LCD) have been applied extensively. Process yield is the most common criterion used in the TFT-LCD manufacturing industry for measuring process performance. The measurement index Spk establishes the relationship between the manufacturing specifications and the actual process performance, which provides an exact measure on process yield. In this paper, we provide two convenient ratio approaches to calculate the lower confidence bounds and critical values extensively for various values of alpha-risk, capability requirements, and sample sizes. Practitioners can use the proposed ratio approaches and procedures to determine whether their process meets the preset capability requirement and make reliable decisions. The convenient ratio approaches can bridge the gap between the theoretical development and factory applications for evaluation of process yields.