Nitrides and Borides

Nitrides and Borides. Nitridation of a MoRe alloy has afforded the new phase h Ol.76 0.24N-  

Phase equilibria in the Re— A1— B system have been studied, and one ternary compound Rc3Al2B was found to be in equilibrium with several binary 

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A.W. Weimer, Carbide, Nitride and Boride Materials, Synthesis and Processing, 1st Ed. Chapman Hall, London, 1997. 

Application of carbo-thermal reduction. This is a synthesis process for the preparation of powders of carbides, nitrides and borides. Carbon may be graphite, coke, pyrolysed organic polymers. A reference process may be the Acheson process for the production of SiC ... 

TABLE 4 Selected Binary Carbides, Nitrides, and Borides with Transition Temperature. 

If carbides, nitrides, and borides could generate such intriguing Tc values, what promise did the ceramic, metallic-conducting oxides hold ... 

Figure 3.35 Classification of chemical vapor infiltration processes. From Carbide, Nitride, and Boride Materials Synthesis and Processing, A. W. Weimer, ed. p. 563. Copyright 1997 by Chapman Hall, London, UK, with kind permission of Kluwer Academic Publishers.

In general, carbides, nitrides, and borides are manufactured in the vapor phase in order to form high-purity powders. This procedure is fundamentally different than a strict CVD process, since in powder synthesis reactors, deposition on seed particles may be desirable, but deposition on the reactor walls represents a loss of product material. As we will see, in CVD, heterogeneous deposition on a surface will be sought. Aside from this issue of deposition, many of the thermodynamic and kinetic considerations regarding gas phase reactions are similar. 

Gogoisi. Y.G. and R.A. Aildricvski Materials Seiencr of Carbides, Nitrides and Borides. Kluwer Academic Publishers. Norwcll. MA. 1999,... 

R. Freer (Ed.) The Physics and Chemistry of Carbides, Nitrides and Borides, (Kluwer, Dordrecht, 1990). 

Werheit, H., in Gogotsi, Y.G., Andrievski, R.A., editors. Materials Science of Carbides, Nitrides, and Borides. Dordrecht Kluwer 1999, p. 65. 

Numerous ceramics are deposited via chemical vapor deposition. Oxide, carbide, nitride, and boride films can all be produced from gas phase precursors. This section gives details on the production-scale reactions for materials that are widely produced. In addition, a survey of the latest research including novel precursors and chemical reactions is provided. The discussion begins with the mature technologies of silicon dioxide, aluminum oxide, and silicon nitride CVD. Then the focus turns to the deposition of thin films having characteristics that are attractive for future applications in microelectronics, micromachinery, and hard coatings for tools and parts. These materials include aluminum nitride, boron nitride, titanium nitride, titanium dioxide, silicon carbide, and mixed-metal oxides such as those of the perovskite structure and those used as high To superconductors. 

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