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陳誠亮 李瑞元 洪詩雯
Cheng-Liang Chen Jui-Yuan Lee Szu-Wen Hung
Introduction tank in order to open the possibilities of inter-fab water reuse.
This concept may be a helpful strategy to solve the water
n a semiconductor factory, water shortage problem.
is one of the indispensable utility
Ifor several process operation.
For example, water is essential for Background
doing backside grinding on wafer,
cleaning process tool, blowing down n academic research, the methodologies on water
air contaminant in scrubber, serving minimization can be generally classified into two broad
as cooling medium to remove extra Icategories: the graphical based pinch analysis (Wang and
heat. Since the large amount of water Smith, 1994a,b; Kuo and Smith, 1998) and the mathematical-
c on s u mpt ion i n s e m ic onductor model based optimization technique (Galan and Grossmann,
factory and the insufficient of water 1998; Huang et al., 1999; Gunaratnam et al., 2005; Karuppiah
resource in recent years in Taiwan, and Grossmann, 2006). In addition, a new design manner
Taiwan Semiconductor Manufacturing with internal RCW tanks to simplify the network complexity
Company(TSMC) puts a lot of effort on and to improve the overall practicability was proposed (Feng
enhancing water recycle rate in each and Seider, 2001; Wang et al., 2003; Zheng et al., 2006; Ma et
fab. However, for the time being, the al., 2007). More recently, Liu Y. Z.’s group (2008) presented a
implementation of water recycle focuses hybrid structure for the design of water networks, in which
on the scope in individual fab. This work the compromise between network complexity and
article aims to propose an inspiring freshwater requirement has been discussed. All of the above-
concept to discuss the opportunities of mentioned works have focused on water integration within
inter-fab water recycle. single fabs. In order to further enhance water recovery
The possibilities of inter-fab water potential, inter-fab water integration should be taken into
recycle is worth exploring, since account (Olesen and Polley, 1996; Liao et al., 2007; Chew et al.,
several TSMC’s Fabs are situated in 2008).
neighboring area in Hsinchu. Besides, This article presents a general formulation for water
the quality and quantity of effluent are integration within a production site, e.g. an industrial park of
different form Fab to Fab because of the different fabs, or a process fab with operations grouped into
difference in processes. The effluent different geographical locations according to the fab layout
which cannot be reused in a certain fab and/or processing tasks. Opportunities for the transfer of
may have the potential to be reuse in water between fabs (or, zones) are considered, and design
another fab. options are fully incorporated in the formulation, so it serves
At present , severa l i n ner-fab as a base to apply various integration schemes. An illustrative
Reuse City Water (RCW) tanks are example is provided to demonstrate the application of the
established to store effluents for further proposed formulation.
reuse in each fab. These effluents may
come from air washer drain, MAU/AHU
condense, AWR reclaim effluent, LSS Methodology
reclaim effluent and some other sources.
The new concept discussing in this Problem Statement
article is to install an inter-fab RCW Given is a total site with a set of plants. Each plant includes a
NEW FAB TECHNOLOGY JOURNAL APRIL 2012 17
