Deposition temperature, diamond-like

Because the ion-assisted processes enable deposition at temperatures less than 100°C, deposition of diamond like coatings has been attempted on a wide range of substrates, e.g., stainless steel, Copper, ceramics,optical materials (plastics, polymers and polycarbonates),glasses,quartz, sapphire,infrared-transmitting optical materials such as germanium, zinc sulfide and zinc selenide, and a variety of electronic grade materials. Although thin films can be produced... 

In ion assisted deposition, there are two methods one is decomposition of hydrocarbon oil using energetic ions and the other is evaporation of graphite with eoncurrent bombardment of the growing film with energetic ions. With these methods, diamond like films with reasonably good properties can be deposited over large areas (1 m ) at low temperatures (< 140°C). 

Lifshitz et al. also studied the effect of carbon ion energy and substrate temperature on diamond like film deposition. They observed that there exists an optimal energy range within which it is possible to obtain good quality diamond like films and that the film quality deteriorates with increasing substrate temperature. 

The excellent properties of the diamond like materials combined with the low deposition temperature and high deposition rate, make these coatings very promising materials for the future. They have many potential applications as protective coatings for industrial products. Of course the properties of diamond like films never match those of diamond. The films are intrinsically smooth and amorphous, and can be used in coating applications where a plane, mechanically hard and wear/corrosion resistant surface is desirable. 

Figure 22 shows RBS spectra of amorphous (Raman spectra similar to amorphous diamond like films) carbonitride films deposited at different temperatures using IBAD. Using this technique, maximum nitrogen incorporation was 33% as compared to 57% required for P-C3N4 stoichiometry. The XPS spectra (C Is and N Is) of the film with 33% nitrogen are shown in Figure 23. From these spectra the percentage of single bonded carbon and nitrogen is obtained...

By using chemical vapour deposition (CVD) technology at a relatively low temperature, Nissin Electric, Kyoto, Japan, claims it is able to apply diamond-like carbon coatings to materials such as plastics and rubber, improving their properties of friction, abrasion resistance and insulation. 

A 1 jim thick diamond-like carbon film is deposited at 500 °C on a Ti alloy substrate. The film with elastic modulus Ef = 500 GPa and Poisson ratio Ui = 0.2, is essentially free of any internal stress at the deposition temperature. When cooled to the temperature 20 °C, however, an equibiaxial compressive mismatch stress of 5 GPa is expected to exist in the film as a consequence of thermal mismatch with the substrate. An unbonded circular patch, 30 gm in diameter, developed at the film-substrate interface during film deposition. Determine whether the film buckles upon cooling to 20 °C If so, determine the temperature at which buckling begins. 

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. 

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