Total resource circulation in chemical mechanical polishing wastewater treatment from semiconductor manufacturing industry: A review
Bi-Cheng Chang, Hsing‐Jung Ho, Atsushi Iizuka
Abstract
With water resources increasingly scarce, water recycling has become essential. The semiconductor industry's rapid growth has led to a surge in water demand. Unlike industrial wastewater, semiconductor wastewater is complex and hazardous, complicating its recycling and necessitates research. During semiconductor processes, chemical mechanical polishing (CMP) involves the grinding of wafers, which generate large amounts of fine particles that contaminate products, requiring significant water use for cleaning. Therefore, CMP accounts for the largest share of water usage, making CMP wastewater a primary focus of water recycling efforts. Semiconductor factories typically use chemical treatment for CMP wastewater, but this treatment generates sludge that cannot be effectively treated, leading to its disposal, even though it contains valuable metals and materials. The semiconductor industry has focused on resource recycling, and zero waste has become a future trend recently, and CMP wastewater containing untreatable sludge has become a critical issue. Here, we provide a comprehensive review of the literature on CMP wastewater treatment. Existing CMP recycling methods mainly focus on water recycling, while effective strategies for recycling the CMP sludge, which contains metals and materials, are lacking. In this study, the total resource circulation concept for CMP wastewater treatment is proposed, encompassing both water and sludge recycling. Membrane filtration shows significant potential for recycling water from CMP wastewater. For sludge recycling, Cu recovery through electrolysis or acid leaching is recommended first. The remaining SiO 2 and CeO 2 can be separated and purified by chemical treatment, ultimately achieving the goal of zero waste of CMP wastewater. • The current state and technologies of CMP wastewater treatment are summarized. • A perspective on the complete resource circulation of CMP wastewater is proposed. • The benefits and promising methods for water recycling are compared. • Effective methods for recycling CMP sludge are suggested.