Diamond like carbon coatings

In parallel to catheter-based delivery, stent-based approaches, such as passive stent coatings (diamond-like carbon, phosphorylcholine, and silicon carbide coatings) and immobilized drug coatings (heparin-coated stents), were evaluated for their ability to inhibit restenosis. Although animal studies demonstrated some promise, none of these technologies were clinically successful for restenosis prevention. The failure of these surface modification technologies further added to the need for the development of DES based on the principles of sustained CDD,... 

Identification of vapor grown diamond is accomplished by X-ray diffraction or electron diffraction using a transmission electron microscope (TEM) and by Raman spectroscopy. Diamond coatings show the characteristic first-order Raman peak for diamond at 1332cm [59]. In many cases, an additional peak located at 1550cm occurs in the Raman spectrum which is attributed to a highly disordered carbon phase (diamond-like carbon) [60]. This diamond-like carbon contains sp and sp hybridized C-atoms which do not coincide with graphite. 

A new form of carbon coating is now available which is neither diamond nor graphite and is known as diamond-like carbon (DLC).bl DLC can be considered as a metastable carbon produced as a thin coating with a broad range of structure and composition.l b[42]... 

Figure 16.7. Transmission and reflection of germaninm coated with diamond-like carbon (DLC).

Erdemir, A., The Role of Hydrogen in Tribological Properties of Diamond-Like Carbon Films," Surf. Coat. Technol., Vol. 146/147,2001, pp. 292-297. 

Grischke, M., BewUogua, K., Trojan, K., and Dimigen, H., Application-oriented Modifications of Deposition Processes for Diamond-like Carbon-based Coatings, Surf. Coat. Technol., Vol. 74/75,1996,pp. 739-745. 

Donnet, C., Recent Progress on the Tribology of Doped Diamond-like and Carbon Alloy Coatings A Review, Surf. Coat. Technol., o. 100/101,1998,pp. 180-186. 

Kimock, F. M. and Knapp, B. J., Commercial Applications of Ion Beam Deposited Diamond-like Carbon (DLC) Coatings," Surf. Coat. Technol, Vol. 56,1993,pp. 273-279. 

Heimberg, J. A., Wahl, K. J., Singer, I. L., and Erdemir, A., "Friction Behavior of Diamond-like Carbon Coatings Time and Speed Effects, Appl. Phys. Lett., Vol. 78, 2001, pp. 2449-2451. 

Delplancke-Ogletree, M. P. and Monteiro, O. R., Wear Behavior of Diamond-Like Carbon/Metal Carbide Multilayers," Surface and Coatings Technology, Vol. 108-109, 1998, pp. 484-488. 

One of such unique coatings is Diamond Like Carbon (DLC). The conventional synthesis of synthetic diamonds requires extremely high temperatures and pressures. By PECVD, Diamond Like Carbon is created under mild conditions by the decomposition of methane in H2/CH4 mixture. The applications of DLC are numerous coatings for cutting tools, optical fibres, electronic devices for reading magnetic tapes, or even protective coatings in chemical reactors. 

CVD Diamond, Diamond-Like Carbon, and Carbonitride Coatings... 

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