Physical vapor deposition laser ablation

Last years considerable efforts have been directed to preparation of metal nanoparticles having a desired diameter and shape. A number of production techniques has been reported such as wet chemical processes, (co-precipitation, complexation, sol-gel), physical vapor deposition, sputtering, and laser ablation methods [1]. The ultimate goal of each technique is fabrication of monodisperse stmctures with a predetermined size, shape and arrangement. 

This work reports the development of a polymeric/sol-gel route for the deposition of silicon carbide and silicon oxycarbide thin films for applications such as heat-, corrosion-, and wear-resistant coatings, coatings on fibers for controlling the interaction with the matrix in ceramic matrix composites, or films in electronic and optoelectronic devices. This method, in which the pre-ceramic films are converted to a ceramic coating either by a conventional high temperature annealing or by ion irradiation, is alternative to conventional methods such as chemical or physical vapor deposition (CVD, PVD), molecular beam epitaxy, sputtering, plasma spray, or laser ablation, which are not always practical or cost efficient. 

Smdies on techniques for thin film deposition divide these into two groups, depending on the nature of the deposition process. Physical methods include physical vapor deposition (PVD), laser ablation, molecular beam epitaxy and sputtering. Chemical methods comprise of gas phase and solution deposition. The gas phase techniques include chanical vapor deposition (CVD) and atomic layer epitaxy (ALE). Spray-pyrolysis deposition, sol-gel, spin-coating and dip-coating are techniques based on solution deposition. 

Due to the short coherent length of HTSCs, only smooth surfaces on structurally perfect layers allow these planar technologies. A number of modem deposition techniques (physical vapor deposition including sputtering, laser ablation, molecular beam epitaxy as well as metallorganic chemical vapor deposition etc. see, e.g., Becht 1996) result in high values of critical temperature and critical current. However compact single-crystalline... 

Physical vapor deposition (PVD) includes the following methods [IJ Evaporation in its simplest form involves heating the source material in vacuum to a temperature at which its partial pressure reaches about 10 - mbar. The preci.se control of composition using multiple. sources for multicomponent films is difficult. A sophisticated version of this method is molecular beam epitaxy (MBE), (requiring UHV conditions, precise control of the temperature of the sources, computer controlled shutters, etc.) capable of producing layers from multi- to monoatomic thicknes.ses. Laser-ablation-a.ssi.sted deposition (LAPVD) and cluster evaporation with ionized cluster beam deposition are among the new developments used to grow films by evaporation. 

Laser ablation deposition (LAD) (film deposition) Physical vapor deposition using laser vaporization as the vapor source. Also called Pulsed laser deposition (PLD). 

SWCNTs exhibit unique physical and chemical properties that make them very attractive candidates for the production of new materials. Carbon nanotubes are made by wrapping up single sheets of graphite, known as graphene, upon themselves to form hollow, straw-like structures. Traditionally, SWCNTs have been prepared by electric arc-discharge, laser ablation and chemical vapor deposition (CVD) methods these techniques produce significant quantities of impurities, such as amorphous and graphitic forms of carbon and encapsulated catalytic metal nanoparticles. 

By now, metal NPs of Au, Ag, Pd, Pt, Cu, Co, and Ni ean be easily synthesized, and many different types are commereially available. NPs can be synthesized either by physical methods such as vapor deposition and laser ablation or by chemical methods sueh as metal salt reduction or micelles (De Jongh 1994 Schmid 1994 Braunstein et al. 1999 Brust and Kiely 2002 Matolin et al. 1990 Masala and Seshadri... 

Although several common physical methods, including chemical vapor deposition (CVD), sonication and laser ablation [23-30], have been used to produce precious metal nanopartides, these will not be discussed at this point... 

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