CVD diamond applications

Some actual and potential applications of CVD diamond are summarized in Table... 

DLC has properties similar to CVD diamond and it is easier to process without the high-temperature substrate requirements and with little restriction on size. However, it has several disadvantages low deposition rate, high internal stress, and availability only in thin coatings. A number of important applications have been developed with a promising future. 

DLC coatings are already in production in several areas (optical and IR windows) and appear particularly well-suited for abrasion and wear applications due to their high hardness and low coefficient of friction. They have an extremely smooth surface and can be deposited with little restriction of geometry and size (as opposed to CVD diamond). These are important advantages and DLC coatings will compete actively with existing hard coatings, such as titanium carbide, titanium nitride, and other thin film... 

Schafer, L., Saltier, M., and Klages, C. P., Upscaling of the Hot-Filament CVD Process for Deposition of Diamond Films on Large-Area Substrates, m Applications of Diamond Films and Related Materials, (Y. Tzeng, et al., eds.), Elsevier Science Publishers, pp. 453-460(1991)... 

With such properties, it could be the ideal material for many semiconductor applications, such as high-power and high-frequency transistors and cold cathodes, or in the harsh environment found in internal-combustion and jet engines. With the advent of CVD diamond, it is now possible to take advantage of these properties. 

CVD diamond films can be used for electrochemical applications, especially in harsh or corrosive environments. Conducting diamond electrodes, made by adding boron to CVD diamond films, are very inert compared to other electrode materials (such as platinum). Such diamond electrodes may find applications in analysis of contaminants, such as nitrates, in water supplies, and even in the removal of those contaminants. 

Spear, K. E., Dismukes, J. P. 1994 Synthetic diamond emerging CVD science and technology. New York Wiley. This book gives a useful description of the chemistry and physics behind diamond CVD, as well as various novel applications for CVD diamond. 

There are numerous materials, both metallic and ceramic, that are produced via CVD processes, including some exciting new applications such as CVD diamond, but they all involve deposition on some substrate, making them fundamentally composite materials. There are equally numerous modifications to the basic CVD processes, leading to such exotic-sounding processes as vapor-phase epitaxy (VPE), atomic-layer epitaxy (ALE), chemical-beam epitaxy (CBE), plasma-enhanced CVD (PECVD), laser-assisted CVD (LACVD), and metal-organic compound CVD (MOCVD). We will discuss the specifics of CVD processing equipment and more CVD materials in Chapter 7. 

The activated CVD diamond techniques can be more attractive in cases where the huge capital investment (several hundred million dollars) required for the HP—HT technology is not available or where the high level of technical knowledge requited for HP—HT synthesis is not available. In addition, most wear-resistant applications requite diamond coatings only of the order of a few micrometers thick. Such coatings can be deposited direcdy on the finished product without the need for further finishing if CVD techniques ate employed. 

When the performance and price of CVD tools compare favorably with those of PCD tools, CVD tools may displace PCD tools in some applications. Woodworking tools represent another major market segment for diamond coatings. Tungsten carbide blades already comprise a large part of the woodworking tool market. CVD-diamond-coated tools have yet to be used in woodworking and, thus, they offer an excellent business opportunity. 

Other potential applications for CVD-diamond coatings include, woodworking tools. 

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