Test Vehicle and Metrology for Defectivity Study in Wet Processes

Controlling defectivity is critical for achieving high yield and performance in advanced CMOS fabrication. Wet processing presents key challenges such as pattern collapse, non-uniform etching, and incomplete cleaning in high-aspect-ratio (HAR) structures. To effectively optimize single-wafer wet process conditions with good across-wafer uniformity, well-designed test vehicles and advanced metrology are indispensable. This paper provides an overview of 300 mm patterned wafer test vehicles, as well as recent developments in advanced metrologies. Together, they offer a robust framework for quantitatively assessing process performance, thereby enabling more efficient and reliable single-wafer processing.