Ceramic deposition technologies

Table 10-2 A comparison of various kinds of ceramic deposition technologies.

Nayral C, Viala E, Fau P, Senocq F, Jttmas JC, Maisonnat A, Chaudret B (2000) Synthesis of tin and tin oxide nanoparticles of low size dispersity for application in gas sensing. Chem Eur J 6 4082- 1090 Nenov TG, Yordanov SP (1996) Ceramic sensors technology and applications. Technomic, Basel Niesen TP, De Guire MR (2001) Review deposition of ceramic thin films at low temperatures from aqueous solutions. 

The technology development that is the key to realizing high frequency modules like this is ceramic film deposition technology applied to resin material. The following three qualities are required of ceramic film. 

J. Akedo, and M. Lebedev, Ceramics Coating Technology Based on Impact Adhesion Phenomenon with Ultrafine Particles-Aerosol Deposition Method for High Speed Coating at Low Temperatnre- , Materia Japan, Vol. 41, No. 7 (2002) pp. 459 66. 

Some catalyst supports rely on a relatively low surface area stmctural member coated with a layer of a higher surface area support material. The automotive catalytic converter monolith support is an example of this technology. In this appHcation, a central core of multichanneled, low surface area, extmded ceramic about 10 cm in diameter is coated with high surface area partially hydrated alumina onto which are deposited small amounts of precious metals as the active catalytic species. 

Solution Deposition of Thin Films. Chemical methods of preparation may also be used for the fabrication of ceramic thin films (qv). MetaHo-organic precursors, notably metal alkoxides (see Alkoxides, metal) and metal carboxylates, are most frequently used for film preparation by sol-gel or metallo-organic decomposition (MOD) solution deposition processes (see Sol-GEL technology). These methods involve dissolution of the precursors in a mutual solvent control of solution characteristics such as viscosity and concentration, film deposition by spin-casting or dip-coating, and heat treatment to remove volatile organic species and induce crystaHhation of the as-deposited amorphous film into the desired stmcture. 

Chemical vapor deposition (CVD) has grown very rapidly in the last twenty years and applications of this fabrication process are now key elements in many industrial products, such as semiconductors, optoelectronics, optics, cutting tools, refractory fibers, filters and many others. CVD is no longer a laboratory curiosity but a maj or technology on par with other maj or technological disciplines such as electrodeposition, powder metallurgy, or conventional ceramic processing. 

This concept later evolved into the Ucarsep membrane made of a layer of nonsintered ceramic oxide (including Zr02) deposited on a porous carbon or ceramic support, which was patented by Union Carbide in 1973 (Trulson and Litz 1973). Apparently, the prospects for a significant industrial development of these membranes were at the time rather limited. In 1978, Union Carbide sold to SPEC the worldwide licence for these membranes, except for a number of applications in the textile industry in the U.S. At that time, SPEC recognized the potential of inorganic membranes, but declassification of the inorganic membrane technology it had itself developed for uranium enrichment was not possible. 

Reactions involving solids are very important in many technologies such as microelectronics processing, ceramics, ore refining, electrochemical deposition and etching, chemical vapor deposition and etching, and food processing. We will consider some of these applications in problems, but we first note several important examples. 

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