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This chapter reviews elements of the study that are not central to the particular technologies studied, but that nonetheless affect both the development and the efficacy of micromanufacturing. Facets of the educational systems, business potentials and practices, governmental policies, and cultural characteristics in all of the countries visited drive and/or enable the technological development necessary for moving micromanufacturing forward. While this chapter makes some effort to compare the U.S. with other countries on these issues, readers can easily conduct similar comparisons from their own perspectives. [ABSTRACT FROM AUTHOR]

For the WTEC study, the mutually agreed-upon working definition of non-lithography machining included, (1) mechanical (traditional) machining and, (2) non-mechanical (non-traditional) machining. In addition to non-lithography-based micromachines, the study panelists were also interested in establishing the impact of microelectromechanical systems (MEMS) and nanoelectromechanical systems (NEMS) on non-lithography-based machining. Examples include the use of MEMS to make a micromold for plastic micromolding, nanoimprint lithography (NIL) and the fabrication of fibers using MEMS spinnerettes. The panel agreed that lithography-based MEMS and NEMS advances are highly oversold in the most public relations-hungry universities and government institutes in the U.S. Although less advertised, nonlithography micromachining, practiced mostly in highly competitive, private companies such as Sankyo Seiki, Samsung, and Olympus is most likely to continue to lead to more practical products faster. These products include lenses for telephone cameras, flat panel displays, automotive parts, microfuel cells, microbatteries, micromotors, and desktop factories (DTFs). Based on the state-of-the-art and current investment levels, both private and government, Germany, Switzerland, Japan, and Korea will gain the most from developments in non-lithography-based machining, given their long tradition with and heavy investment in this field. The U.S. over the last twenty years has emphasized lithography-based MEMS with outstanding research results and a dominant market position, but as many MEMS products have become commodity products, Asian countries stand to reap more benefits in the near future from it. Actually, even MEMS foundries, which are very hard to make profitable in the U.S., are moving more and more to Asia; Olympus in Japan has already the largest MEMS foundry in the world. During our Asia trip we gained, in general, more from our industrial visits than from the visits to academic institutions—this is understandable as micromanufacturing is very applied and product-driven, and academia is not. We believe that to succeed in nonlithography- based machining a stronger-than-usual link with industrial partners and academia is required. In this regard we are now behind in the U.S., although it was in the U.S. that the trend of academia/industry collaborations started. The links between industry and academia are now better in both Europe and in Asia. It was speculated that technology transfer offices in U.S. academia have become so unwieldy that they prevent smoother and better collaboration with industry. In some showrooms of the Asian hosts, the panel came to realize that none of the products on display were manufactured in the U.S. anymore. As noted in Chapter 4, new product demands are stimulating the invention of new materials and processes. The loss of manufacturing goes well beyond the loss of one class of products. If a technical community is dissociated from the product needs of the day, say those involved in making larger flat-panel displays or the latest mobile phones, communities cannot invent and eventually cannot teach effectively anymore. Chapter 4 lists several such new manufacturing processes. A yet more sobering realization is that we might invent new technologies, say in nanofabrication, but not be able to manufacture the products that incorporate them. It is naïve to say that those new products will still be designed in the U.S. because the latest manufacturing processes and newest materials need to be understood and used in order for a good design to be developed.… [ABSTRACT FROM AUTHOR]

This chapter focuses on metrology, sensors and controls for micromanufacturing. In general, a variety of sensors are employed in micromanufacturing. Many of them are used for metrology, and in particular dimensional metrology. Most are used on production machines to provide feedback during production. Few metrology systems for process and product control are available. The sensors and metrology systems available for product and process analysis are, in general, slow and not readily implemented. From a metrology and sensing perspective, the currently available systems are mostly two-dimensional in nature. Most of the measurement systems are fairly slow, which makes them suitable for R&D as their measurement speed limits their utility on actual production lines. Controllers fall into two architecture categories, open and closed (standard computer numerical control (CNC) controller architecture). In most cases, commercially available systems employ more traditional closed architecture controllers, while research and development teams tend to use open architecture systems. For most manufacturing systems, process control is a desired capability. In many cases it is achieved by measuring parameters from both the process and the product and adjusting process parameters to improve the quality of the part. In general, this approach is far from being achieved in the micromanufacturing field as the actual measurement of part and process parameters in real-time is limited to a few very special instances. Furthermore once a measurement is made, the process must be tuned according to the process model. In most cases, such models do not exist. Thus, in order to effectively achieve process control and quality enhancement, improved real-time metrology systems and sensors are needed along with models that accurately describe the various manufacturing processes at the micro level such that true process control can be enabled. [ABSTRACT FROM AUTHOR]

Manufacturing processes convert raw material into desired parts to make usable and saleable products. All manufacturing processes are evaluated and then selected for specific applications based on the type and amount of energy involved, the process mechanism and its capability (including accuracy and repeatability), environmental effects, and economy. In addition to these measures, micromanufacturing processes also need to be evaluated on the quality of the removal (or plastic deformation or addition) of the smallest amount of material in one cycle, as well as the achievable precision of the related micromanufacturing equipment. This chapter begins by describing the status of the micromanufacturing processes observed during the WTEC visits to Asia and Europe. The state-of-the-art of micromanufacturing processes in the U.S. is also included in this chapter. The sites visited in Asia and Europe include industry, universities and research organizations. Specific issues of process mechanism, modeling and simulation, surface integrity, and scaling effects are summarized in the second part of this chapter. [ABSTRACT FROM AUTHOR]

Materials play an important role in manufactured goods. Materials must possess both acceptable properties for their intended applications and a suitable ability to be manufactured. These criteria hold true for micromanufacturing, in which parts have overall dimensions of less than 1 mm. This chapter begins by reviewing materials usage in Asian and European research in micromanufacturing, categorized by manufacturing process. Following that, specific treatment is given to materials factors that are unique to micromanufacturing. [ABSTRACT FROM AUTHOR]

The purpose of this chapter is to review the existing capabilities that may be used to design parts that will be micromanufactured without lithography-based processes. In the past five to 10 years, non-lithography-based meso- and microscale (NLBMM) parts have seen increased use in medical applications, consumer products, defense applications, and several other areas. These technologies promise to have an impact on the economy, improve health and safety, raise our standard of living, and form a middlescale stepping stone by which the benefits of nanotechnology may be accessed. The technologies used to design NLBMM parts and the processes and equipment used to fabricate them are in a nascent stage. These technologies have been, for the most part, borrowed from the design practices of macroscale engineering and very large-scale integration (VLSI). At present, most designers have difficulty ascertaining the appropriate time to use pre-existing design knowledge, theory and tools. Designers must be able to assess the suitability of pre-existing technology for the design of NLBMM parts. Otherwise, design processes will be long and iterative, with the result that the products' benefits will be either delayed or lost. As designers, we must understand the nature of this new technology and work hard to generate the design knowledge, theories and tools that will enable the widespread and rapid advance of NLBMM technology. Given the nascent state of NLBMM technology, this chapter focuses on the technologies that "should be." Some of these technologies may be borrowed or adapted from the macroscale and VLSI design domains, whereas others will have to be fundamentally different. This chapter aims to explain the aspects of NLBMM parts design that are fundamentally unique and the circumstances in which these unique differences call for new design knowledge, theories and tools. Toward this end, this chapter contains discussions on the following topics: (1) the reasons why unique requirements exist for the design of NLBMM parts, (2) the existing knowledge and practices that may be borrowed to design NLBMM parts, and (3) the gaps between existing technologies and the requirements for NLBMM part design. The topics are arranged so that members of disparate design communities (e.g., decision theorists, hardware and mechanical designers, design theorists, industrial designers, and process design specialists) may make use of the knowledge gained during this study. [ABSTRACT FROM AUTHOR]

For the purpose of this study, the term micromanufacturing refers to the creation of high-precision three-dimensional (3D) products using a variety of materials and possessing features with sizes ranging from tens of micrometers to a few millimeters (See Figure 1.1). While microscale technologies are well established in the semiconductor and microelectronics fields, the same cannot be said for manufacturing products involving complex 3D geometry and high accuracies in a range of non-silicon materials. At the same time, the trends in industrial and military products that demand miniaturization, design flexibility, reduced energy consumption, and high accuracy continue to accelerate—especially in the medical, biotechnology, telecommunications, and energy fields. By and large, countries with traditional strengths in manufacturing, such as Japan and Germany, have continued to invest heavily in recent years in micromanufacturing R&D for several reasons. First, the demand from the global market for ever-smaller parts and systems at reasonable cost and superior performance is strong. This demand tends to drive the high-end research. Second, the prospects of multidisciplinary research are causing companies increasingly to blend material science, biology, chemistry, physics, and engineering to speed up technology innovation and thereby new applications based on microtechnology. [ABSTRACT FROM AUTHOR]