Diamondlike carbon film

There are many applications for diamonds and related materials, e.g., diamondlike carbon films, and there are potential applications for Fullerenes and carbon nanotubes that have not yet been realised. However, the great majority of engineering carbons, including most of those described in this book, have graphitic microstructures or disordered graphitic microstructures. Also, most engineering carbon materials are derived firom organic precursors by heat-treatment in inert atmospheres (carbonisation). A selection of technically-... 

Tsai, H., and Bogy, D. B., Characterization of Diamondlike Carbon Films and Their Application as Overcoat on Thin-Film Media for Magnetic Recording, J. Vac. Sci. Technol. A, 5(6) 3287-3312 (Nov/Dec 1987)... 

J. Andersson, R.A. Erck, and A. Erdemir, Frictional Behavior of Diamondlike Carbon Films in Vacuum and under Varying Water Vapor Pressure, Surf. Coat. Technology 163-164,535-540 (2003). 

Mousinho AP, Mansano RD, Massi M et al (2003) Micro-machine Fabrication Using Diamondlike Carbon Films. Diamond Relat Mater 12 1041-1044... 

Zarrabian M, FourchesCoulon N, Turban G, Marhic C, Lancin M. Observation of nanocrystalline diamond in diamondlike carbon films deposited at room temperature in electron cyclotron resonance plasma. Appl Phys Lett 1997 70 2535-7. 

C. Donnet, A. Erdemir (ed,). Tribology of Diamondlike Carbon Films Fundamentals and Applications, Springer, New York, 2008. 

A. Erdemir, C. Donnet, Tribology of Diamondlike Carbon Films Current Status and Future Prospects (topical review), Journal of Physics D Applied Physics, 39, (2006) 311-327. 

Figure 17 Ultraviolet-Raman spectra acquired using 244-nm excitation for an unhydrogenated taC H film, and a taC H film annealed under vacuum for 15 min [49]. (Reproduced from Diamond and Related Materials, 8, Adamopoulos G., et al., Ultraviolet Raman characterisation of diamondlike carbon films, pp, 541-544. Copyright 1999, with permission from Elsevier Science.)... 

Table 1 Properties, Applications, and Type of Diamondlike Carbon Films...

Diamondlike Carbon Films Generated by a Hot-Filament Chemical Vapor... 

Most of the solid lubricants mentioned above owe their low-Mction characteristic primarily to a lamellar or layered crystal structure (see two of them in Figure 6.1 as typical examples). When present at a sliding contact interface, these solids shear easily along their atomic shear planes and thus provide low friction. Some of the solid lubricants do not have such layered crystal structures, but in applications, they too provide very low friction and wear. For example, certain soft metals (In, Pb, Ag, Sn, etc.), PTFE, a number of solid oxides and rare earth fluorides, diamond and diamondlike carbons, etc., can also provide fairly good lubrication despite the lack of a layered crystal structure like the ones shown in Figure 6.1 [1]. In fact, diamondlike carbon films are structurally amorphous but provide some of the lowest friction and wear coefficients among all other solid materials available today [8]. 

Erdemir, A. and Donnet, C., Tribology of diamond and diamondlike carbon films An overview, in Wear Materials, Mechanisms and Practices, G. W. Stachowiak, ed., Jdm Wiley Sons, 2006, pp. 191 222. 

The work on carbon nitride solids is strongly related to research on diamondlike carbon (DLC) materials [5, 6]. DLC materials are thin film amorphous metastable carbon-based solids, pure or alloyed with hydrogen, which have properties similar to that of crystalline diamond (high hardness, low friction coefficient, high resistance to wear and chemical attack). This resemblance to diamond is due to the DLC structure, which is characterized by a high fraction of highly cross-linked sp -hybridized carbon atoms. To obtain this diamond-like structure... 

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... 

In Section 2 we showed that the properties of amorphous carbon vary over a wide range. Graphite-like thin films are similar to thoroughly studied carbonaceous materials (glassy carbon and alike) in their electrode behavior. Redox reactions proceed in a quasi-reversible mode on these films [75], On the contrary, no oxidation or reduction current peaks were observed on diamondlike carbon electrodes in Ce3+/ 41, Fe(CN)63 4. and quinone/hydroquinone redox systems the measured current did not exceed the background current (see below, Section 6.5). We conventionally took the rather wide-gap DLC as a model material of the intercrystallite boundaries in the polycrystalline diamond. Note that the intercrystallite boundaries cannot consist of the conducting graphite-like carbon because undoped polycrystalline diamond films possess excellent dielectric characteristics. 

Diamondlike Carbon and Hard Carbon-Based Sensors Sensors that are based upon diamond technology include thermistors, pressure and flow sensors, radiation detectors, and surface acoustic wave devices [103]. The relative ease of depositing prepattemed, dielectrically isolated insulating and. semiconducting (boron-doped p type) diamond films has made polycrystalline diamond-based sensors low-cost alternatives to those based on conventional semiconductors. Diamondlike carbon and diamond films synthesized by chemical... 

In the diamond stmcture, carbon atoms are present in sp hybridization, with a tetrahedral stereochemistry and a face-centered cubic stmcture that is shown in Fig. 2.1. Besides natural diamond, synthetic diamond has been produced since General Electric first announced its successful high-pressure synthesis in 1955. Sintered polycrystalline diamond, different types of diamond films, and diamondlike carbon are other types of diamond-related synthetic materials, some of which are noncrystalline [13, 19] these solids have their own terminology [10, 20]. Unhke other carbonaceous solids, diamond has a rather limited and specific relevance to adsorption. Indeed, ever since the publication of a pioneering work... 

Gielisse, P.J. (1998). Mechanical properties of diamond, diamond films, diamondlike carbon and like-diamond materials. In Handbook of Industrial Diamonds and Diamond Films (M.A. Prelas, G. Popovici, and L.K. Bigelow, eds). Marcel Dekker, Chapter 3, pp. 49—88. 

S. Aisenberg, and R. Chabot, Ion-Beam deposition of thin films of diamondlike carbon, J. Appl. Pl s., 42 2953-2958 (1971)... 

In Volume 2 ceramic hard materials are highlighted in the light of their applications. Chapter 1 of Part III concisely reviews the history of diamond and diamondlike super abrasive tools while Chapter 2 and 3 are concerned with the application of chemical vapor deposited diamond and diamond-like carbon films. These sections... 

Nanodiamonds indicate synthetic diamond materials that have sizes or feature sizes (e.g., grain sizes) between 1 and lOOnm, generally including two forms particulate and thin film. Because the nanodiamond thin film is actually composed of nanosized columnar crystals or grains, the material is also known as nanocrystalline diamond. Due to its close relationship and similarity to nanodiamonds, nanostructured diamondlike carbon has also attracted considerable attention. In the following sections, these carbon nanostructures are discussed separately. 

The level of sp -bonded carbon can be detected either electrochem-ically or by Raman spectroscopy. Figure 14 shows a series of Raman spectra for the films shown in Fig. 13. It can be seen that the one-phonon diamond line at 1333 cm decreases in amplitude and increases in width from 12 to 43 cm as the CH4/H2 ratio increases. The scattering intensity centered at ca. 1525 cm also increases with increasing CH4/H2 ratio, indicative of higher levels of sp -bonded carbon. This nondiamond carbon is actually a mixture of sp - and sp -bonded carbon-diamondlike carbon and is not graphitic in nature. The higher defect density, due to the increased secondary nucleation, causes the increased line width and the increased opacity from the nondiamond carbon causes the re-... 

Structure. The use of synthetic semiconductive diamond thin films in electrochemistry has only recently been reported. Former designations such as diamondlike carbon (DLC) are now obsolete and so are not used in this book. By contrast with its other carbon allotropes, in diamond each carbon atom is tetrahedrally bonded to four other carbons using sp -hybrid orbitals. 

Lopez-Rios [33] also used hydrogen and methane in an ultrahigh-vacuum chamber to generate diamond films (as well as diamondlike carbon) on silicon substrates. Figure 10 shows spectra before and after silver deposition. The spectral enhancement caused by SERS is clearly shown, for there was no spectrum without silver deposition. The asymmetry of the cubic diamond peak at 1332 and the structure at 1242 are attributed to phonon excitation. 

Within the last several years, a number of companies have investigated the application of Raman spectroscopy to process analysis. A review of the scholarly and patent literature reveals several examples PCI3 reactions, titanium dioxide production, diamondlike carbon (DLC) films production, polymeric fiber property detection, applications to gasoline, aromatic production, chlorosilane production, and gas-phase measurements. In Section in, some of these applications will be reviewed in order to illustrate the application of Raman spectroscopy to process chemistry and control. 

The application of Raman spectroscopy to the studies of diamondlike carbon (DLC) films has been reviewed in this volume (Chap. 22 and 24) and elsewhere [147]. Recent hardware developments involve the application of UV excitation to the study of DLC films [148-151]. Recently, a patent was granted to SI Diamond Technology [152] covering the application of UV-excited Raman spectroscopy for the characterization of carbon films used in the construction of a field-emission cathode. UV-excited Raman spectroscopy, however, is likely to be limited to the research environment due to the cost and complexity of the instrumentation. 

---