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For such products newprocesses need to be employed, like the energy beam pro-cesses, based on the principle, that the energy carried on a beam can remove material by melting, vaporization or ab-lation. These processes, developed during the last decadedue to their application in the electronics industry may belisted: Photolithography, X-ray lithography, Micro EDM,Electron beam machining, Focused ion beam, Laser beammachining, Excimer and femtosecond lasers, Scanning Tun-neling Microscopy (STM) and Atomic Force Microscopy(AFM).Probably, the most important application of nanotechnol-ogy is the manufacturing of microchips. By reducing the di-mensions of the chip components their number on the chipcan be increased, making them even faster because the elec-tric signal has to travel less distance between them. The di-mensions of chip components cannot be reduced in size anyfurther with today’s manufacturing methods, because pho-tolithography does not permit the manufacturing of particleswith dimensions of 100 nm or less. Therefore, new methodsare investigated, based, either on the same physical princi-ples as photolithography, like LIGA, which is a deep etchingprocess based on lithography, electroplating and molding oron completely new ideas.Electron beam machining, Focused ion beam and Laserbeam machining are new processes, providing the energy formaterial removal in the form of heat. The main advantageof these methods, for both the tool and the workpiece, isthe virtually zero machining force. Although the mechanical A.G. Mamalis / Journal of Materials Processing Technology 161 (2005) 1–9Fig. 2. Time line for discovery of superconductors [2].properties of the workpiece do not affect the machining pro-cess, its thermal properties, like the melting point, the boilingpoint and the heat capacity, greatly influence the machiningcharacteristics, which may cause problems. Furthermore, due 3 Fig. 3. Mirror surfaces made of superhard materials [2]. Fig. 4. The nanotechnology tree [4]. 4 A.G. Mamalis / Journal of Materials Processing Technology 161 (2005) 1–9Fig. 5. Nanotechnology: present and potential impact [5]. to the excessive heat generated on the machined surface, aheat-affected zone is developed, since the molten materialremaining on the machined surface re-solidifies during cool-ing, whilst the structure of the layers underneath the surfacechanges, resulting in phase transformations in ferrous mate-rials, which may induce residual stresses and changes in thesurface hardness. A typical application of Focused ion beamis the sharpening of diamond cutting tools to a cutting edgeof 10 nm.In Excimer and Femtosecond laser processing, very highquantum energy is induced into the workpiece, exceeding theenergy among atoms, permitting each molecule to be decom-posed into atoms, which are removed from the workpiece.The great advantage of this method, in contrast with the pre-vious methods, is that the developed heat-affected layer isvery small. This particular feature of these processes allowsfor performing very accurate cutting surfaces almost with-out defects. Their main disadvantages are the low machiningspeed and, thus the low efficiency, and the high cost of therequired equipment.In order to use ultraprecision machines in the nanome-ter regime, three-dimensional control of the position of thetool and the workpiece is necessary, obtained with CNC ul-traprecision machine systems, that can provide such control,and with the aid of new measuring methods as the ScanningTunneling Microscopy and the Atomic Force Microscopy. Inparticular, Scanning Tunneling Microscopy is very importantin nanotechnology, because it makes possible atom manipu-lation. The main disadvantage of this method is that it can beonly applied to conducting materials and, therefore, AtomicForce Microscopy has been designed to overcome this disad-vantage. Note, that, the above described nanotechnology pro- cesses need to be controlled for surface integrity and dimen-sional accuracy, which constitutes the field of nanometrology.Atomic Force Microscopy is the latest device developed forthat reason but Laser and X-ray interferometers are also usedin nanometrology, which is a specific area of nanometrol-ogy in the form measurement, e.g. the roundness or the flat-ness of the machined workpiece. This kind of metrology isvery demanding and difficult to achieve, because there aremany sources of uncertainty involved, especially in large-scale structures, like astronomical mirrors, where the mea-suring of roughness, dimensions and shape is essential forthe functionality of the structure.