Water Conservation in Semiconductor Manufacturing
Chiarello, Ron ; Foster, Justin; Farmen, Lisa
(Etalon Technologies, San Francisco, CA)
Innovations in semiconductor manufacturing must keep pace with nearly constant new product innovations and business needs. Today, manufacturing faces more challenges than at any time in its history as 300 mm wafers, new chemicals, materials, processes and equipment are simultaneously introduced. This leads to increases in consumables and emissions, and combined with the location of Fabs around the world, it is now required that an environmentally correct approach be taken from the outset. In this paper examples are given of the positive impacts environmental technologies have to realize significant gains in cost savings and capacity increases, while minimizing environmental impact. Examples are given for the reduction of ultrapure water (UPW) use. The cost of obtaining water, the construction and maintenance of large-scale deionization plants and the treatment of wastewaters now add significantly to manufacturing costs. A transparent solution is to reduce water consumption, thereby lowering both fixed and operating costs as well as putting less strain on natural resources. The approach presented here has had great success in reducing UPW consumption, and also providing optimized processes that provide shorter process times, higher tool utilization and higher wafer throughputs - all of which lead to a lower cost-of-ownership. Specific examples are presented for front-end-of-line surface prep and chemical-mechanical polishing. Water use reduction at point of uses also impacts wastewater treatment and these issues will be addressed. This technology has been implemented in many fabs world wide resulting in UPW savings (70%), rinse time reductions (60%), increases throughput of (88%) and annual cost savings and cost avoidance of $250K to $8 million per fab.
[abstract as .pdf]