Increasingly severe global water shortages have prompted semiconductor manufacturers to consider using recycled wastewater and seawater as sources for ultrapure water for manufacturing semiconductors.
Production of ultrapure water from these water sources requires advanced technology capable of removing salts, silica, boron, urea, alcohols, and other impurities. Urea poses a particular challenge, as it impacts both the safety of drinking water and the quality of ultrapure water used in photolithography processes for semiconductor manufacturing. Urea is hard to remove, however, owing to its small molecular size and electrically neutral nature, much like boron in seawater. Improving removal rates for urea and boron while maintaining high water production rates has been a significant challenge in developing RO membranes.
By innovating the RO membrane manufacturing process, Toray has developed a new membrane structure control technology that allows selective water permeation and enhances the removal of urea, boron, alcohol, and other substances. These efforts have culminated in the TBW-XHR series of RO membrane elements, whose urea removal efficiency is double that of conventional systems, achieving high water permeability at low pressure.
The company employed advanced analytical technology from Toray Research Center Inc, in developing this product. Internal evaluations found that urea removal efficiency is nearly 90%, contributing to a stable supply of high-quality ultrapure water needed by advanced semiconductor fabs. The technology reduces urea levels by half compared with conventional methods, supporting ultrapure water production from recycled wastewater.
Toray will present the technology underlying this product at the annual conference of the International Desalination and Reuse Association in Abu Dhabi, United Arab Emirates, from 8–12 December 2024.
