Chemical vapour deposition MOCVD

The alkoxides and aryloxides, particularly of yttrium have excited recent interest. This is because of their potential use in the production of electronic and ceramic materials,in particular high temperature superconductors, by the deposition of pure oxides (metallo-organic chemical vapour deposition, MOCVD). They are moisture sensitive but mostly polymeric and involatile and so attempts have been made to inhibit polymerization and produce the required volatility by using bulky alkoxide ligands. M(OR)3, R = 2,6-di-terr-butyl-4-methylphenoxide, are indeed 3-coordinate (pyramidal) monomers but still not sufficiently volatile. More success has been achieved with fluorinated alkoxides, prepared by reacting the parent alcohols with the metal tris-(bis-trimethylsilylamides) ... 

Singh HB, Sudha N (1996) OrganoteUurium precursors for metal organic chemical vapour deposition (MOCVD) of mercury cadmium telluride (MCT). Polyhedron 15(5-6), 745-763... 

The thermal decomposition of Cp substituted silicon compounds with the elimination of pentamethylcyclopentadiene (Cp I I) turns out to be synthetically very useful. As shown in equations 43-45, extreme conditions are necessary to selectively cleave the respective Si—C(Cp ) bond94-96. In this context, it is important to mention the use of cyclopentadienyl silicon compounds in the metalorganic chemical vapour deposition (MOCVD) process or in related techniques95,96. 

The assumption of equilibrium which is implicit in EQN (1) is expected to be satisfied at the high temperatures at which metal-organic chemical vapour deposition (MOCVD) growth of nitrides is carried out. At lower temperatures, such as those used in molecular-beam epitaxy (MBE), deviations from equilibrium may occur. 

III-V nitride films were grown by the two-flow metalorganic chemical vapour deposition (MOCVD) method, details of which are described elsewhere [1]. The growth was conducted at atmospheric pressure. Sapphire with (0001) orientation (C-face), of two-inch diameter, was used as a substrate. 

Ce(R CO.CH.CO.R )3 are readily oxidized (O2) to Ce(R CO.CH.CO.R )4, such as Ce(acac)4(R = R = Me), Ce(dbm)4(R = R = Ph), and Ce(tmhd)4 (R = R = Mc3C), generally found to have square antiprismatic structures, though Ce(tmhd)4 is closer to dodecahedral. These are volatile dark red solids that are soluble in solvents such as benzene and chloroform they are volatile, with vapour pressures high enough for Metal Organic Chemical Vapour Deposition (MOCVD) use, whilst they have also been studied as possible alternatives to lead compounds for petrol additives. 

Some years ago the thermolysis of organopnictogens was considered an esoteric subject of limited interest. The topic has been transformed into one of the growth points of hetero-organic chemistry because of the enormous economic potential of metal organic chemical vapour deposition (MOCVD) processes for the production of III-V type of... 

The bis-Cp titanium bis(/-butanethiolato) and bis(ethanethiolato) complexes have been used as a single-source precursors for the preparation of thin films of titanium sulfides by metal-organic chemical vapour deposition (MOCVD). The crystal and molecular structures of the precursor complexes have been determined for comparison with homologous complexes of the general formula Cp2Ti(SR)2.1618... 

A few compounds have been studied for other reasons. These include trimethylaluminium [64] and trimethylgallium [65] which are of interest because of their use in metal organic chemical vapour deposition (MOCVD) processes. The compounds were also studied because the interactions between methyl groups in the same molecule are a continuing source of fascination. Tetramethyltin was studied for the same reason [66]. 

Chemical vapour deposition (CVD) is the delivery (by uniform mass transport) of a volatile precursor or precursors to a heated surface on which reaction takes place to deposit a thin film of the solid product the surface must be hot enough to permit reaction but cool enough to allow solid deposition. Multilayer deposition is also possible. Metal-organic chemical vapour deposition (MOCVD) refers specifically to use of metal-organic precursors. 

Metal-organic chemical vapour deposition (MOCVD) refers specifically to use of metal-organic precursors. 

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