Diamond-like layer

In contact the resonance frequency varies during scanning and hence the amplitude and the phase of the cantilever vibration vary as well if the excitation frequency of the transducer is kept constant. This amplitude and phase contain information about the local tip-sample stiffness, and hence can be used as imaging quantities, see Fig. 3. It shows an AFAM-amplitude image of a lead calcium titanate film annealed at 650° C. The size of the images is 2 x 2 pm. The cantilever material was coated with a conductive diamond-like layer. The overall spring constant was... 

PVD coatings provide considerable potential in terms of the sliding behavior. The production of anti-wear and anti-friction coatings through PVD processes has become part of the state of the art. This allows a layer deposition on almost all substrate materials with almost any chemical composition. Metallic layers but also such as carbon, diamond, and diamond-like layers can be produced. The usual layer thicknesses range from 2 to 6 pm, and can be applied at temperatures of 150 to 500 °C. Low alloy steels can be coated without loss of hardness and good adhesion due to the low coating temperatures. 

By subjecting boron nitride (a white powder) to high pressure and temperature small crystals of a substance harder than diamond, known as borazon, are obtained. This pressure-temperature treatment changes the structure from the original graphite-like layer structure (p. 163) to a diamond-like structure this hard form can withstand temperatures up to 2000 K. 

Voevodin, A. A., Walck, S. D., andZabinski, J. S., Architecture of Multilayer Nanocomposite Coatings with Super-Hard Diamond-Like Carhon Layers for Wear Protechtion at High Contact Load, Wear, Vol. 203-204,1997, pp. 516-527. 

Plasma Synthesis The use of plasma methods has lead to a new range of materials having unique properties. An example is the family of amorphous elemental hydrides (eg cr-C H Of -Si H or-P H) which contain a variable proportion of H from almost zero to 50 atomic %. The carbon films, known variously as "hard carbon", "diamond-like carbon", " a-carbon" etc (9 ) - These layers are of considerable interest because of their optical and abrasion-resistant properties etc (Table I). The properties of these Gr-carbon films, can be tailored by modifying the plasma parameters. 

Mechanical properties, electrical properties, thermodynamic stability, surface chemical activity, and other important parameters can all be discussed relative to the structure of the carbon network, composed of both aromatic layers and 3D-arranged (diamond-like) phases. 

In graphite, which can be considered as a giant two-dimensional molecule from the series of condensed rings, the bonding between the separate layers is very weak, being due, as in molecular lattices, to Van der Waals-London interaction. The now infinite system of n electrons results in metallic conduction, only, however, in the plane of the rings Boron nitride has perhaps also a diamond-like form as well as the common graphite-like modification (p. 235). 

Nucleation on an Intermediate Layer of Diamond-like Amorphous Carbon... 

The HRTEM study of diamond nucleation and growth on copper TEM grids in HFCVD by Singh provides direct evidence for the formation of a diamond-like amorphous carbon layer. The intermediate layer is 8-14 nm thick, in which small diamond microcrystallites approximately 2-5 nm across were embedded (Fig. 6a), and large diamond crystallites were observed to grow from these microcrystallites (Figs. 6b-c). 

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