Chemical vapor deposited oxides/nitrides

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. 

Surface moisture is a problem of concern in ceramic powders, and IR has been used to characterize the surface groups of -OH and -H [58,63,64]. IR was also applied to characterize chemically bound hydrogen in chemical vapor-deposited silicon nitride at various ammonia-silane ratios [65]. Surface silicon dioxide on SiC powders was determined by photoacoustic IR and diffuse reflectance IR spectroscopy [66,67]. IR spectroscopy was also used to study the surface oxidation of SiC and SisN4 [68,69]. 

Choi D J, Fischback D B, Scott W D, Oxidation of chemically-vapor-deposited silicon nitride and single-crystal silicon , J Am Ceram Soc, 1989 72(7) 1118-1123. 

Dielectric Deposition Systems. The most common techniques used for dielectric deposition include chemical vapor deposition (CVD), sputtering, and spin-on films. In a CVD system thermal or plasma energy is used to decompose source molecules on the semiconductor surface (189). In plasma-enhanced CVD (PECVD), typical source gases include silane, SiH, and nitrous oxide, N2O, for deposition of siUcon nitride. The most common CVD films used are siUcon dioxide, siUcon nitride, and siUcon oxynitrides. 

Chemical vapor deposition (C VD) is a versatile process suitable for the manufacturing of coatings, powders, fibers, and monolithic components. With CVD, it is possible to produce most metals, many nonmetallic elements such as carbon and silicon as well as a large number of compounds including carbides, nitrides, oxides, intermetallics, and many others. This technology is now an essential factor in the manufacture of semiconductors and other electronic components, in the coating of tools, bearings, and other wear-resistant parts and in many optical, optoelectronic and corrosion applications. The market for CVD products in the U.S. and abroad is expected to reach several billions dollars by the end of the century. 

Chemical Vapor Deposition- Deposition of silicon oxide films is accomplished by CVD equipment. Either plasma CVD or ozone oxidation is used. Blanket tungsten films are also deposited by CVD equipment to create contact and via plugs. Polysilicon and silicon nitride films are deposited in hot-wall furnaces. TiN diffusion barrier films are deposited by either sputtering or CVD, the latter giving superior step coverage. 

Ma, Y., Yasuda, T. and Lucovsky, G. Fixed and trapped charges at oxide-nitride-oxide heterostructure interfaces formed by remote plasma-enhanced chemical-vapor-deposition. Journal of Vacuum Science Technology 11, 1533-1540 (1993). 

Franz et al. [93] developed a palladium membrane micro reactor for hydrogen separation based on MEMS technology, which incorporated integrated devices for heating and temperature measurement. The reactor consisted of two channels separated by the membrane, which was composed of three layers. Two of them, which were made of silicon nitride introduced by low-pressure chemical vapor deposition (0.3 pm thick) and silicon oxide by temperature treatment (0.2 pm thick), served as perforated supports for the palladium membrane. Both layers were deposited on a silicon wafer and subsequently removed from one side completely... 

In the fifteen years since publication of the first edition of Comprehensive Coordination Chemistry (CCC, 1987), group 5 chemistry has been part of the intensive development of ceramic, optical, and magnetic materials based upon metal borides, nitrides, phosphides, oxides, and sulfides. A major impetus came from the discovery of the high-temperature superconducting oxides. In addition, the search for new routes to these materials via sol-gel or chemical vapor deposition techniques has spurred growth in metal amido, oxo, alkoxo, thio, and carboxylato chemistry. 

Nanoscale materials are those with dimensions less than 100 nm. Most of the nanomaterials used, such as oxides, sulfides, nitrides, and others are well known, in many cases since the beginning of civilization. In recent decades, it has been observed that specific properties of these materials, useful in biomedical, electromagnetic, mechanical, and catalytic areas," can be enhanced by reducing particle size to nanoscale dimensions. Many synthetic strategies have been developed in order to obtain nanometric materials with specific properties. Thin films of powders, in particular, have been the subject of current investigations. Studies of new synthetic approaches for nanometric films are intimately connected with the development of the chemical vapor deposition technique, which has widespread acceptance and is used for the production of important supplies for semiconductor electronic applications. ... 

Roels N, Platon F, Aubreton J, Desmaison J (1990) Chemical vapour deposition of silicon nitride study of the interrelationships of experimental parameters, carbon content, oxidation and wear properties. In Spear KE, Cullen GW (eds) Proceedings of the 11th international conference on chemical vapor deposition. Electrochemical Society, Pennington, NJ, pp717-723... 

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