Microlithography is a general name for any manufacturing process that can create a minutely patterned thin film of protective materials over a substrate, such as a silicon wafer, in order to protect selected areas of it during subsequent etching, deposition, or ion implantation operations.[
The term is normally used for processes that can reliably produce features of microscopic size, such as 10 or less. The term nanolithography may be used to designate processes that can produce nanotechnology features, such as less than 100 .
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Microlithography is a microfabrication process that is extensively used in the semiconductor industry and also manufacture microelectromechanical systems.
Processes
Specific microlithography processes include:
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Photolithography using light projected on a photosensitive material film (photoresist).
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Electron beam lithography, using a steerable electron beam.
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Nanoimprinting
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Interference lithography
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Magnetolithography
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Scanning probe lithography
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Surface-charge lithography
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Diffraction lithography
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These processes differ in speed and cost, as well as in the material they can be applied to and the range of feature sizes they can produce. For instance, while the size of features achievable with photolithography is limited by the wavelength of the light used, the technique it is considerably faster and simpler than electron beam lithography, that can achieve much smaller ones.
Applications
The main application for microlithography is fabrication of integrated circuits ("electronic chips"), such as solid-state memories and . They can also be used to create diffraction gratings, microscope calibration grids, and other flat structures with microscopic details.
See also
[John N Helbert (2001), Handbook of VLSI Microlithography. Elsevier Science, 1022 pages. ]
[Bruce W. Smith and Kazuaki Suzuki (2007): Microlithography: Science and Technology, 2nd Edition. CRC Press, 864 pages. ]
