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Printed electronics is a set of printing methods used to create electrical devices on various substrates. Printing typically uses common printing equipment suitable for defining patterns on material, such as screen printing, flexography, gravure, offset lithography, and inkjet. By electronic industry standards, these are low cost processes. Electrically functional electronic or optical inks are deposited on the substrate, creating active or passive devices, such as thin film transistors; capacitors; coils; resistors. Printed electronics is expected to facilitate widespread, very low-cost, low-performance electronics for applications such as flexible displays, smart labels, decorative and animated posters, and active clothing that do not require high performance.〔 Coatanéa, E., Kantola, V., Kulovesi, J., Lahti, L., Lin, R., & Zavodchikova, M. (2009). Printed Electronics, Now and Future. In Neuvo, Y., & Ylönen, S. (eds.), Bit Bang – Rays to the Future. Helsinki University of Technology (TKK), MIDE, Helsinki University Print, Helsinki, Finland, 63-102. ISBN 978-952-248-078-1. http://lib.tkk.fi/Reports/2009/isbn9789522480781.pdf〕 The term ''printed electronics'' is often related to organic electronics or plastic electronics, in which one or more inks are composed of carbon-based compounds. These other terms refer to the ink material, which can be deposited by solution-based, vacuum-based or other processes. Printed electronics, in contrast, specifies the process, and, subject to the specific requirements of the printing process selected, can utilize any solution-based material. This includes organic semiconductors, inorganic semiconductors, metallic conductors, nanoparticles, nanotubes, etc. For the preparation of printed electronics nearly all industrial printing methods are employed. Similar to conventional printing, printed electronics applies ink layers one atop another.〔 H.-K. Roth et al., Materialwissenschaft und Werkstofftechnik 32 (2001) 789.〕 So the coherent development of printing methods and ink materials are the field's essential tasks. The most important benefit of printing is low-cost volume fabrication. The lower cost enables use in more applications.〔 J.M. Xu, Synthetic Metals 115 (2000) 1.〕 An example is RFID-systems, which enable contactless identification in trade and transport. In some domains, such as light-emitting diodes printing does not impact performance.〔 Printing on flexible substrates allows electronics to be placed on curved surfaces, for example, putting solar cells on vehicle roofs. More typically, conventional semiconductors justify their much higher costs by providing much higher performance. ==Resolution, registration, thickness, holes, materials== The maximum required resolution of structures in conventional printing is determined by the human eye. Feature sizes smaller than approximately 20 µm cannot be distinguished by the human eye and consequently exceed the capabilities of conventional printing processes.〔 A. Blayo and B. Pineaux, Joint sOC-EUSAI Conference, Grenoble, 2005.〕 In contrast, higher resolution and smaller structures are necessary in much electronics printing, because they directly affect circuit density and functionality (especially transistors). A similar requirement holds for the precision with which layers are printed on top of each other (layer to layer registration). Control of thickness, holes, and material compatibility (wetting, adhesion, solvation) are essential, but matter in conventional printing only if the eye can detect them. Conversely, the visual impression is irrelevant for printed electronics.〔 U. Fügmann et al., mstNews 2 (2006) 13.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「printed electronics」の詳細全文を読む スポンサード リンク
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