Profiling cost and profitability potential associated with recovery, recycle, and reuse of spent rinse waters from semiconductor wafer rinsing processes

This paper profiles the environment, safety and health (ESH) cost and profitability potential associated with recycling spent rinse waters from semiconductor wafer rinsing processes. An ESH cost modeling software tool was used to (a) account for activities that drive environment, safety and health costs, (b) estimate their economic impact, and (c) calculate the profitability potential between ultrapure water (UPW) nonrecycling and recycling options. The study found that the ESH cost model provided a flexible, low maintenance, decision-oriented approach for understanding the full cost and potential profitability of owning recycling systems. The financial analysis cost study looked at a typical 200 mm wafer fabrication facility processing 480000 wafers annually, using 500 gal/min of UPW and recycling at 70%. Both direct and gal/direct costs were calculated. The financial analysis study showed that the annual incremental cost difference between nonrecycle ($2.8 M) and recycle ($1.5 M) is approximately ($1.28 M). This annual cost reduction taken over the 15 year estimated productive/economic life of the system, results in a net present value of ($4335034)