In electronic waste recycling industry, printed wire boards (PWBs)/integrated chips (ICs) recycling is one of the most challenge tasks due to the fact that PWBs/ICs are diverse and complex in terms of materials and components makeup, as well as the original equipment manufacturing processes. In this paper, we will present environmental benign solution to recover valuable metals from PWB and integrated circuit chips (ICs) dissembled from waste PWB, based on green chemistry methodologies. We will demonstrate that the process/chemistry can selectively separate and recover precious metals from base metals. The 95%-99% recovery rate of precious metals can be achieved from the recycling of PWB and integrated circuit chips.

With <2% of the mass in US landfills, electronic waste (e-waste) accounts for 70% of hazardous materials.Approximately 5% by weight of e-waste consists of valuable secondary resource stock-printed wiring boards (PWBs).Those PWBs with high metal value are sold to overseas smelters and those PWBs with low value are sent to Asia or Africa where the integrated circuits (ICs) are manually desoldered and the trace precious metals are collected either by open burning or from chemical leaching with toxic chemicals such as hot aqua-regia and cyanide, which lead to environmental pollution and human exposure to hazardous chemicals.This paper reports novel cradle-to-cradle PWBs recycling processes and enhanced process efficiencies based on green chemistry and green engineering methodologies for the complete recycling of PWBs.We will describe that one can recover metals and valuable components from end-of-life (EOL) PWBs using cost effective, sustainable, and scalable methods.This includes both chemical desoldering and precious metal reclaim on ATMI's eVOLV TM PWBs recycling line.

Advanced Technology Materials, Inc. (ATMI) has developed a novel process based on green chemistry and green engineering methodologies for reclaiming valuable materials from waste electronics. We have demonstrated that we can recover metals and valuable components from end-of-life products using cost-effective, sustainable, and scalable methods (e.g., systems that are closed-loop, energy efficient and environmentally benign). This includes both chemical desoldering and precious metal reclaim from printed wiring boards (PWBs) and integrated circuits (ICs) near room temperature with all metals recovered and resold. Our current system is processing approximately 400 lbs. per hour of high value printed wiring boards.

Reclamation of wafers results in significant cost savings for integrated circuit manufacturers. To successfully reclaim wafers, particle, metallic, and organic contamination must be removed from the wafer surface after etch-back, grinding, lapping, and polishing. The cleaning and surface conditioning processes used during the reclaim process will be presented in this chapter. Specification for reclaiming wafers, especially removal of copper and other metal contamination and methods to obtain a pristine, particle-free surface are discussed. Comparison of different processes, including standard RCA cleaning compared to simplified cleaning, will be shown and their advantages and disadvantages discussed, and evidence will be provided for how the chemistry and process affects the yield and defect levels of the reclaimed wafers.

Chemical formulations are used because of the specific properties of the components in the mixture working in a synergistic fashion. Each component plays of role in the overall performance of the formulation. The key components for stripping and cleaning formulations are the base chemicals, additives, and in some cases, water for semi-aqueous cleaners. Design of chemical formulations according to solubility principles is used to tailor the solvents to the solute. Practical considerations are also given for designing a formulation.

In semiconductor processing, test wafers are used as particle monitors, film thickness monitors for deposition and oxide growth measurements, dry/wet etch rate monitors, CMP monitors, as well as characterizing new and existing equipment and processes. Depending on fab size and capacity, monthly test wafer usage can be tens of thousands or more. Due to the ever increasing demand for silicon between the IC and solar markets and the high cost of 300mm wafers, chip manufacturers are increasing their efforts to reduce overall spending on silicon - currently by far the largest non equipment related cost [1]. One approach taken by many chip makers is the concept of extending the usable life of test wafers by re-using them as many times as possible through a reclaim process.