How Ultrapure Water Impacts Yield in Wafer Fabrication
In wafer fabrication, yield is everything. A small percentage change can decide whether a fab is profitable or under pressure. While advanced tools, materials, and process recipes get most of the attention, one of the most powerful yield drivers often operates quietly in the background — ultrapure water. Water touches the wafer more than almost any other substance during manufacturing. It cleans, rinses, and prepares surfaces hundreds of times before a chip is complete. When this water is truly pure, it protects yield. When it is not, yield suffers — sometimes in ways that are difficult to trace. Yield Starts With a Clean Surface Every process step in wafer fabrication depends on a perfectly clean surface. Before a new layer is deposited or patterned, the wafer must be free from particles, ions, and residues. Ultrapure water is used after etching, chemical cleaning, CMP, and lithography to ensure nothing unwanted remains behind. If contaminants are present in the rinse water, they ...