Metalorganic precursors

C) under mass transport controlled conditions, only depends on the concentration of the group 13 metalorganic precursor. 

The result is a composite with a very fine homogeneous distribution of TiN of nanometer size in the Si3N4 matrix. Higher starting amounts of Ti02 result in Si2N20 formation [525, 573]. The composites can also be prepared from metalorganic precursors [574]. 

The metalorganic precursor compounds that have been most commonly used to grow thin films of semiconductors and related materials are listed below in Table I, along with the currently available vapor pressure data. These precursors are typically pyrophoric liquids or high-vapor-pressure solids. The simple metal alkyls (methyl and ethyl derivatives) are the most often employed for the growth of III-V compound semiconductors since they have reasonably high vapor pressures and can be readily delivered using a H2 carrier gas and precursor source temperatures conveniently near room temperature. 

Jones, A. C. (1993). Metalorganic precursors for vapour phase epitaxy, J. Crystal Growth 129, 728-773. 

Winter, C. H., The Chemical vapor deposition of metal nitride films using modem metalorganic precursors. Aldrichimica Acta 33 (2000) 3-12 and references therein. 

Thin-film deposition technique that uses metalorganic vapor-phase precursors to form a solid thin film on substrate surfaces. The metalorganic precursor provides a volatile source of inorganic elements to a growth surface which are then thermally disassociated from their organic components on the substrate surface. 

Whatever route is used, one of these three or any other similar ones, the transformation from metalorganic precursors to the final inorganic product can be roughly divided... 

Metalorganic precursors for SiC include polysUanes, polycarbosilanes, silicon-acetylene and silicon-olefin poly-... 

In recent years, a number of coating process technologies have been developed, based on chemical vapour deposition (CVD), such as metalorganic precursor CVD [32] and plasma enhanced CVD (PECVD) [33], as alternative techniques to deposit columnar structures. Results reported so far, while promising, do not seem to offer a significant improvement in performance or durability over... 

Matarial Science.- Relevant review articles are the use of metalorganic precursors for vapour phase epitaxy, precursor requirements for the growth of GaAs and AlGaAs by chemical beam epitaxy,and the use of aluminium-nitrogen compounds for AIN deposition.203... 

The new technique involves using chemical precursors, that facilitate the synthesis of nanomaterials containing phases of desired composition and crystal structure. Metalorganic precursors are particularly attractive since they can be used to (i) yield a high fraction of end product and (ii) obtain phases with a selected stoichiometry. Consequently, the possibility now exists for producing nanocomposite materials in significant amounts. These may contain a diverse range of phases such as intermetallic, silidde, boride, nitride, carbide and oxide phases. 

Despite their cost, metalorganic precursors generally offer more flexibility with respect to the choice of the solvent, which can be crucial for the quality of the resulting product, and afford nanoscale particles irrespective of liquid droplet size. 

Mazdiyasni and his colleagues have long advocated the use of metalorganic precursors, including alkoxides, acetylacetonates (acac), and trifluoro-acac for the preparation of pure oxides. For example, zirconia can be prepared by decomposing zirconium tert-butoxide in a furnace at 325 to 500°C in an atmosphere of nitrogen [121] ... 

Fig.l Variation of the metal content in M-Ti02 films as a function of the metalorganic precursor mole fraction in the input gas phase. The Ag content being close to the detection limit it is given as relative content deduced by SIMS (a) while XPS data are reported for Cu (b). Coatings with a composition in the colored area are inactive according to the microbiological JIZ test. 

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