Ion-beam-assisted deposition

The use of ion bombardment during film growth can modify film properties. For example, IBAD of Si02 with 300 eV 02 ions during growth can change the refractive index. It is also possible to 

These changes are possible because the incident ion beam may 

There are many considerations when choosing a substrate for thin-film growth  

Substrate homogeneity. In many single-crystal substrates this is not a problem. But in materials that are heavily twinned, such as LaAlOs and LaGaOs, twin boundaries that propagate through the substrate can act as nucleation sites. In bicrystal and polycrystal substrates the presence and orientation of the grain boundaries affect film microstructure and properties. 

If we want to form epitactic films, then we also need to consider the following  

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These materials are produced in monolithic form or as coatings. The coatings are generally applied by CVD on ceramic substrates and by sputtering, electron-beam evaporation, or ion-beam assisted deposition on steel substrates (see Appendix). 

In ion-plating deposition, the substrate and the deposited film (as it forms) are subj ected to bombardment by particles (ions, atoms, molecules) which alter the formation process and the properties of the coating.The process is also calltd ion-beam assisted deposition (TOAD). 

Toshiyuki, Hayashi, Akihito, Matsumuro, Mutsuo, Mura-matsu, Masao, Kohzaki, and Katsumi, Yamaguchi, "Wear Resistance of Carbon Nitride Thin Films Formed by Ion Beam Assisted Deposition," Thin Solid Films, Vol. 376, No. 1-2, 2000,pp. 152-158. 

In order to express the importance of the ions to the growth process quantitatively, two related quantities can be defined the fraction of arriving ions per deposited atom, / , and the kinetic energy transferred by ions per deposited atom, Emd, - These quantities are used in ion-beam-assisted deposition in order to relate material properties to ion flux and energy [421]. Their definition is... 

In the following paragraphs, reports on XPS studies of a-C N H films are discussed. Most of the work that is discussed is not related to usual plasma deposition, but is related to ion-beam deposition, ion-beam assisted deposition, or other methods, because only a very few wide scope XPS studies on plasma-deposited a-C(N) H films were done up to this moment. Nevertheless, these results bring useful information on the role of hydrogen in the structure of a-C(N) H films. 

Ion assisted deposition (IAD), 14 441-442 Ion-beam amorphization, 14 447 Ion-beam-assisted deposition (IBAD),... 

Saha et al. [109] have proposed an improved ion deposition methodology based on a dual ion-beam assisted deposition (dual IBAD) method. Dual IBAD combines physical vapor deposition (PVD) with ion-beam bombardment. The unique feature of dual IBAD is that the ion bombardment can impart substantial energy to the coating and coating/substrate interface, which could be employed to control film properties such as uniformity, density, and morphology. Using the dual lABD method, an ultralow, pure Ft-based catalyst layer (0.04-0.12 mg Ft/cm ) can be prepared on the surface of a GDL substrate, with film thicknesses in the range of 250-750 A. The main drawback is that the fuel cell performance of such a CL is much lower than that of conventional ink-based catalyst layers. Further improvement... 

Saha, M. S., Gullb, A. R, Allen, R.J., and Mukerjee, S. High-performance polymer electrolyte fuel cells with ultralow Pt loading electrodes prepared by dual ion-beam assisted deposition. Electrochimica Acta 2006 51 4680-4692. 

It is suggested that P occupies an empty tetrahedral position. Yubero et al. (2000) claim, on the basis of Rutherford backscattering spectroscopy, that up to 0.04 mol mol of Ar could be incorporated in the structure of hematite prepared from Fe(CO)s by ion beam assisted deposition in the presence of 0 and Ar", followed by annealing at 500 °C. 

In addition to C onions, C atoms condense into various kinds of chemically bonded forms, and they are known to have excellent physical properties depending on the bonding nature. This means that research and applications not only in the materials science but also in other scientific fields are expected. At JAERI, the optimum growth conditions have been successfully obtained for the preparation of high-quality Cgo, diamondlike carbon, and nanocrystalline diamond by means of ion-beam-assisted deposition [80-82]. The susceptibility of Ni/Cgo thin films to thermal treatment, the formation of nanocrystalline diamond and nanotubes due to codeposition of Co and Ceo, and the surface modification of glassy... 

S. M. Rossnagel andj. J. Cuomo, "Ion-Beam-Assisted-Deposition and Synthesis," MRS Bulletin, 40 (Feb./Mar. 1987). 

The methods mostly used for nano-cBN deposition are ion-beam-assisted deposition (IBAD) [199] mass selected ion beam deposition (IBD) [200] ion plating [201] RF- or magnetron sputtering [202] and laser deposition [203] (Fig. 13). 

What is the primary assumption underlying the application of the thermal spike model to ion-beam assisted deposition of C-N materials ... 

The introduction of unbalanced magnetron sputtering, in which part of the argon plasma can impinge on the substrate, allows ion bombardment of the coating as it forms. The use of ion-beam assisted deposition can be used concurrently or sequentially. This technique is described separately later in the chapter. 

Gulla et al. reported several thin-layer electrodes with superior performance and stability. Using a dual-ion beam-assisted deposition technique, they coated a Pt outer layer ( 50 nm thick, 0.08 mg Pt/cm ) directly onto GDLs with either a Co or Cr inner layer ( 50 nm thick). These bilayered electrodes showed a mass-specific Pt activity more than 50% higher at 900 mV than that for a single Pt layer on GDLs. No ionomers were present in the electrodes. 

Cotell, C.M., Schiestel, S., Carosella, C.A., Flom, S., Hubler, G.K., Knies, D.L. Ion-beam assisted deposition of Au nanocluster/Nb2O5 thin films with nonlinear optical properties. Nucl. Instr. and Meth. in Phys. Res. B 127/128, 557-561 (1997)... 

Ramaswamy N, Arruda TM, Wen W, Hakim N, Saha M, Gulla A, Mukcrjee S (2009) Enhanced activity and interfacial durability study of ultra low Pt based electrocatalysts prepared by ion beam assisted deposition (IBAD) method. Electrochim Acta 54 6756-6766 Wu J, Yuan XZ, Martin JJ, Wang H, Zhang J, Shen J, Wu S, Merida W (2008) A review of PEM fuel cell durability degradation mechanisms and mitigation strategies. J Power Sources 184 104-119... 

Ohtsu, N., Saito, K., Asami, K., and Hanawa, T. (2006) Characterization of CaTi03 thin films prepared by ion-beam assisted deposition. Surf. Coat. TechnoL, 200 (18/19), 5455-5461. 

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