Advanced Quality Control (AQC) of Silicon Wafer Specifications for Yield Enhancement for Smart Manufacturing
Chen–Fu Chien, Yin-Hung Chen, Mei-Fang Lo
Abstract
Silicon wafers are critical raw materials for semiconductor fabrication. Wafer characteristics and specifications will affect the yield of integrated circuits fabricated on the wafer. As critical dimensions for semiconductor manufacturing are shrinking, defining wafer characteristics and specifications for the corresponding semiconductor devices is crucial for yield enhancement and smart manufacturing. However, to the best of our knowledge, none of existing studies have investigated the relationship between wafer characteristics and process variables. Focusing on the needs in real settings, this study aims to develop an advanced quality control (AQC) solution for raw wafers for yield enhancement in advance, in which the UNISON framework is employed to derive the optimal raw material specifications for different products. For validation, an empirical study was conducted in a leading semiconductor fab to derive rules to effectively improve the quality indices including defect count, overlay errors, anti-contamination capability, and yield. The results have shown practical viability of the proposed AQC approach as associated effort to enhance existing approaches including advanced process/equipment control (APC/AEC). Indeed, the developed solution is implemented in real settings as partial effort for enabling Industry 3.5.