Fundamentals of wafer rinse processes and the interactions with water conservation and recycling in semiconductor manufacturing plants

Production and distribution of ultra-pure water (UPW) in semiconductor manufacturing plants has significant environmental and economic impact. Most of the UPW is used for wafer rinsing. In recent years two strategies have been used to lower water usage in fabs: one is the minimization of rinse water usage by more efficient rinse tools and techniques; the other is the reuse and/or recycle of water recovered from various applications, particularly from the final stages of rinse. The implementation of these methods with minimum contamination risk requires better understanding of the fundamentals of the rinse process, the dynamics of the rate limiting step(s), and the interactions between rinse and recycle.