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Increasing systemic error during copper CMP (Chemical Mechanical Planarization) is due to the uneven surfacetopography generated during the process. A mechanistic model based on a fundamental understanding of the processconstituents was proposed to predict material removal rates and the post CMP topography. Two synergisticmechanisms were proposed: 1) chemically dominant behavior is explained by the repetitive removal and formation ofa protective layer on copper surface and chemical dissolution during the process, 2) mechanically dominant removalmechanism is due to the material behavior of copper at the nano-scale and subsequent oxidation and removal of theplastically deformed copper. As a step forward to optimize the process and the manufacturing system, this model wasextended to explain pattern dependent variability during copper CMP.

Currently available life cycle assessment (LCA) tools provide only a rough estimation of the environmental impact of different manufacturing operations (e.g. energy consumption). To address this limitation, a web-based and application programming interface (API) based process analysis software tools were developed to estimate the energy consumption of a computer numerically controlled (CNC) machine tool operation and to evaluate its environmental impact as a first step towards sustainable manufacturing analysis. Acceleration/deceleration of machine tool axes and the direction of axes movement were considered to estimate the total energy demand and processing time of the machine tool operation. Several tool path generation schemes were tested to analyze the energy consumption and resulting green house gas emission of CNC machine tool operation. It showed that tool path generation schemes affect the amount of energy and the processing time required to machine the same part, and location of the machining resulted in different amount and characteristics of green house gas emission.

Production engineering is under constant pressure to satisfy demands for improved productivity while simultaneously achieving high workpiece quality. In addition, environmental awareness is a growing concern to address. New technologies represent new opportunities for increased productivity. This paper shows how the combination of speed stroke grinding and high speed machining can boost both process performance and workpiece quality. Theoretical consideration is validated by experiments and analyzed regarding energetic and environmental aspects. Only a thorough choice of process parameters leads to high process sustainability. Furthermore, lower tensile stresses can positively leverage increased manufacturing effort to optimize the overall product life cycle.

Since machine tools are used extensively throughout their functional life and consequently consuming valuable natural resources and emitting harmful pollutants during this time, this study reviews strategies for characterizing and reducing the energy consumption of milling machine tools during their use. The power demanded by a micromachining center while cutting low carbon steel under varied material removal rates was measured to model the specific energy of the machine tool. Thereafter the power demanded was studied for cutting aluminum and polycarbonate work pieces for the purpose of comparing the difference in cutting power demand relative to that of steel.

The growing demand to reduce environmental impacts has encouraged manufacturers to pursue various green manufacturing technologies and strategies. These solutions, though, may have a direct impact on several productivity metrics including availability, quality, service life, and cost. This study presents an approach to evaluate the trade-offs between the environmental, performance, and financial impacts of green machining technologies by combining green manufacturing principles into life cycle performance evaluation. The approach is validated by investigating the implications of reducing the processing time by increasing the cutting speed and chip load to green a horizontal milling process.

The environmental impact of most consumer products is dominated by their use phase. However, theseimpacts tend to be driven by the manufacture of the product’s components since components fabricatedwith higher precision typically allow the product to operate at higher efficiencies. This paper investigatesthe relationship between precision and life cycle environmental impacts by extending the traditional LCAmethodology to evaluate the impact of manufacturing process precision on the functional performance ofa product during its use phase. The implications of this relationship to manufacturing decision-makingare also discussed as sustainability concerns may support the use of higher precision processes.deee

Millisecond scale benzotriazole (BTA) adsorption kinetics in acidic aqueous solution containing 0.01 M glycine and 0.01 M BTA have been investigated. Chronoamperometry was used to measure current densities on the surface of a micro-copper electrode in pH 4 aqueous solutions containing 0.01 M glycine with or without 0.01 M BTA. In the presence of BTA the current density decreased as the inverse of the square root of time for a few seconds due to adsorption of BTA. At potentials above 0.4 V saturated calomel electrode the current leveled off after a second or so due to the formation of a Cu(I)BTA monolayer on the copper surface. Based on these data a governing equation was constructed and solved to determine the initial kinetics of BTA adsorption. Analysis shows that material removal during copper chemical mechanical planarization (CMP) in this slurry chemistry occurs mostly by direct dissolution of copper species into the aqueous solution rather than mechanical removal of oxidized or pure copper species and that each interaction between a pad asperity and a given site on the copper removes only a small fraction of the Cu(I)BTA species present at that site.

Strategies to reduce energy demand in manufacturing processes are becoming necessary due to the growing concern of carbon emissions and the expected rise of electricity prices over time. To guide the development of these strategies, the results of a life-cycle energy consumption analysis of milling machine tools are first highlighted to show the effect of several factors such as degree of automation, manufacturing environment, transportation, material inputs, and facility inputs on environmental impact. An overview of design and operation strategies to reduce energy consumption is thereafter presented including the implementation of a Kinetic Energy Recovery System (KERS), a process parameter selection strategy, and a web-based energy estimation tool.

Solid state drives (SSDs) show potential for environmental benefits over magnetic data storage due to their lower power consumption. To investigate this possibility, a life-cycle assessment (LCA) of NAND flash over five technology generations (150 nm, 120 nm, 90 nm, 65 nm, and 45 nm) is presented to quantify environmental impacts occurring in flash production and to investigate their trends over time. The inventory of resources and emissions in flash manufacturing, electricity generation and some chemicals are based on process data, while that of fab infrastructure, water and the remaining chemicals are determined using economic input-output life-cycle analysis (EIO-LCA) or hybrid LCA. Over the past decade, impacts have fallen in all impact categories per GB. Sensitivity analysis shows that the most influential factors over the life-cycle global warming potential (GWP) of flash memory are abatement of perfluorinated compounds (PFCs) and reduction of electricity-related emissions in manufacturing. A limited comparison between the life-cycle energy use and GWP of a 100 GB laptop SSD and hard disk drive shows higher impacts for SSD in many use phase scenarios. This comparison is not indicative for all impact categories, however, and is not conclusive due to differences in boundary and functional unit.

Implementing green manufacturing, as the first step towards sustainable production, has been growing in interest and importance over the last few years. The opportunities for developing advanced manufacturing capabilities while, at the same time, reducing the impact of manufacturing on energy use, water and resource consumption and, overall, green house gas emissions and carbon footprint are numerous. This paper reviews the background, vocabulary and motivation for green manufacturing and highlights the competitive opportunities for manufacturers who embrace, seriously, this growing movement. The terms "green" and "sustainable" are defined in a manufacturing context, metrics and tools for assessing manufacturing are described, and some concrete examples of how to begin and what are others doing are given. Some of the future directions of green manufacturing are discussed.

Several strategies in the areas of process planning, machine design, and machine operation exist to develop green machine tools. Before exploring different solutions, a life-cycle energy analysis is first presented to guide subsequent investigation. The results of this analysis provide a range of the environmental impact of the use of machine tools in different types of manufacturing facilities. One strategy explored energy consumption reduction by process parameter selection. The specific energy of the NV1500 DCG was characterized to estimate the environmental burden of the manufacture of a standard part under various cutting conditions. Finally, we present a software solution to implement green machining strategies to aid process planning. This software is a “dashboard” program that estimates environmental impact for a given NC program.

CIRP has had a long history of research and publication on the development and implementation of sensor monitoring of machining operations including tool condition monitoring, unmanned machining, process control and, more recently, advanced topics in machining monitoring, innovative signal processing, sensor fusion and related applications. This keynote follows a recent update of the literature on tool condition monitoring and documents the work of the cutting scientific technical committee in CIRP. The paper reviews the past contributions of CIRP in these areas and provides an up-to-date comprehensive survey of sensor technologies, signal processing, and decision making strategies for process monitoring. Application examples to industrial processes including reconfigurable sensor systems are reported. Future challenges and trends in sensor based machining operation monitoring are presented.

Multiple frameworks have been developed for sustainable or green manufacturing systems and products, which can be roughly divided into life cycle assessment methodologies and life-cycle assessment standards. Methodologies include process LCA, input-output LCA, and hybrid LCA; standards include the ISO14044 standard, the US EPA Life-Cycle Engineering Standard, and various emerging greenhouse gas protocols. We discuss in this paper the differences between these frameworks, and define the specific use cases where each framework is best suited. We achieve this by looking at manufacturing systems and processes across spatial and temporal levels of complexity and assess the suitability of existing frameworks at each level. The main questions addressed are: (1) what are appropriate LCA methodologies for different scales of manufacturing? (2) how do existing standards apply across various levels of manufacturing?

Recently, an increasing number of customers of the machine tool industry have applied life cycle costing (LCC) to compare the cost-effectiveness of different investment options. These concepts have mainly been used to address maintenance costs since these have proven to be one of the most important cost drivers. The approach of life cycle performance (LCP) broadens LCC by considering the relationship between the costs and benefits of a machine over its entire life cycle. With the increasing importance of environmental consciousness, it has become crucial to incorporate environmental impact when evaluating machines. A framework is presented that enables the integration of green manufacturing principles into LCP-evaluation. The role of interoperability within this framework is also discussed.

A life-cycle energy consumption analysis of a Bridgeport manual mill and a Mori Seiki DuraVertical 5060 has been conducted. The use phase incorporated three manufacturing environments: a community shop, a job shop, and a commercial facility. The CO2-equivalent emissions were presented per machined part. While the use phase comprised the majority of the overall emissions, the manufacturing phase emissions were significant especially for the job shop, which is not as efficient as the other facilities due to its inherent need for flexibility. Since the Mori Seiki is heavier, the manufacturing phase of this machine tool had a greater impact on emissions than the Bridgeport. Transportation was small relative to the use phase, which was dominated by cutting, HVAC, and lighting. These results highlight areas for energy reductions in machine tool design as well as the importance of facility type to the manufacture of any product.

Environmental assessment of photovoltaic systems is a rich field, with representations of many technologies, regions and methodologies. This paper discusses some of the factors that strongly affect the outcomes of studies, encourages detailed reporting of normalization parameters and scope, and discusses a cradle to grave framework for benchmarking life cycle assessments of photovoltaic systems.

In this study, we performed a specific precision grinding process in an attempt to improve the mirror-quality finish and tribological characteristics of titanium nitride based coating films (TiN, TiCN, and TiAIN). The ground surfaces were highly smooth with no evidence of cracking, chipping, or peeling, demonstrating that the hard coating films were finished uniformly. For the TiAIN coating, a significant high level mirror-quality finish was achieved with an average roughness Ra of 4 nm. In addition, for all films, the employed grinding process led to superior tribological characteristics. In the case of the TiN film, the precision grinding process produced a carbon- and copper-rich surface layer, as well as higher compressive residual stress.

Reducing the energy consumption of machine tools can significantly improve the environmental performance of manufacturing systems. To achieve this, monitoring of energy consumption patterns in the systems is required. It is vital in these studies to correlate energy usage with the operations being performed in the manufacturing system. However, this can be challenging due to complexity of manufacturing systems and the vast number of data sources. Event stream processing techniques are applied to automate the monitoring and analysis of energy consumption in manufacturing systems. Methods to reduce usage based on the specific patterns discerned are discussed.

One of the major concerns in deburring technology is centered on how to predict the size and shape of burrs to insure uniform removal and, if this is possible, how to design the process or product in advance to minimize or control the burr size. This paper reviews some of the research done over the past several years on this important topic. The paper includes a discussion of burrs in conventional machining, process planning for burr minimization as well as micromachining applications.

Determination of the life-cycle environmental and human health impacts of semiconductor logic is essential to a better understanding of the role information technology can play in achieving energy efficiency or global warming potential reduction goals.This study provides a life-cycle assessment for digital logic chips over seven technology generations, spanning from 1995 through 2010. Environmental indicators include global warming potential, acidification, eutrophication, ground level ozone (smog) formation, potential human cancer and non-cancer health effects, ecotoxicity and water use. While impacts per device area related to fabrication infrastructure and use-phase electricity have increased steadily, those due to transportation and fabrication direct emissions have fallen as a result of changes in process technology, device and wafer sizes and yields over the generations. Electricity, particularly in the use phase, and direct emissions from fabrication are the most important contributors to life-cycle impacts. Despite the large quantities of water used in fabrication, across the life cycle, the largest fraction of water is consumed in generation of electricity for use-phase power. Reducing power consumption in the use phase is the most effective way to limit impacts, particularly for the more recent generations of logic.

The material removal characteristics of a silicon wafer were experimentally investigated with respect to the chemical dissolution and mechanical abrasion of the wafer during silicon chemical mechanical polishing (CMP) using an alkali-based slurry. The silicon surface without native oxide is rapidly dissolved by the slurry containing an amine agent, which effectively leads to the reduced hardness of the loaded silicon wafer due to Si–Si bond breaking during polishing. The abrasive particles in the slurry easily remove the reacted silicon surface, and the removal rate and wafer non-uniformity for abrasive concentrations of 1.5–3 wt% are better than those for other concentrations because of the low and steady coefficient of friction (COF) owing to the evenness of abrasive particles between the wafer and pad. Also, it was found that a high slurry flow rate of 700–1000cm3/min improves wafer non-uniformity owing to the reduced temporal variation of temperature, because the slurry acts as a good cooling source during polishing. However, the removal rate remains almost constant upon varying the slurry flow rate because of the effective dissolution characteristic of the slurry with abundant amine as an accelerator, regardless of the reduction of average temperature with increasing slurry flow rate. In the break-in process used to stabilize the material removal, the viscoelastic behaviors of the pad and the ground wafer surface with native oxide and wheel marks cause a temporal change of the friction force during polishing, which is related to the removal rate and wafer non-uniformity. As a result, the stabilization of removal rate and wafer non-uniformity is achieved through a steady-state process with elevated temperature and reduced COF after a total polishing time of 60 min, based on the removal process of the wafer surface and the permanent deformation in the viscoelastic behavior of the pad.