Metal-organic vapor deposition

Interest in barium yttrium alkoxides stems from metal organic vapor deposition experiments for the preparation of superconducting thin films. The compound [Y4Ba20(0Et)8(dmp)6] (where dmp = B C CHC Bu1) has been prepared by the reaction of Y50(0Pr1)13 with Ba(OEt)2 (PPOH) in the presence of dmpH.167 The structure contains seven-coordinate yttrium atoms with... 

Chour KW, Chen J, Xu R. Metal-organic vapor deposition of YSZ electrolyte layers for solid oxide fuel cell applications. Thin Solid Films 1997 304 106-12. 

Galoppini E, Rochford J, Chen H, Saraf G, Lu Y, Hagfeldt A, Boschloo G (2006) Fast electron transport in metal organic vapor deposition grown dye-sensitized ZnO nanorod solar cells. J Phys Chem B 110(33) 16159-16161... 

With the use of epitaxial growth methods such as molecular beam epitaxy (MBE) or metal organic vapor deposition (MOCVD), it is possible to grow single crystalline ternary alloy systems such as AljrGai j As or quaternary systems such as Ga lhi xAsyPi y with controlled composition as well as to form heterostructures by growing one compound semiconductor epitaxially on top of another compound semiconductor. (Epitaxy means that the lattice periodicity is maintained across the growth interface.)... 

Different approaches to introduce the metal in the framework ( incipient wetness impregnation, MOCVD loading of highly PCPs host lattices by metal organic vapor deposition, etc.) provide wide opportunities for the modification of the adsorption properties of MOFs/COFs [32,110,115,184-186]. 

Cyclopentadienyl compounds have been thoroughly investigated as suitable precursors to rare earth doped semiconductors in MOCVD (metal-organic chemical vapor deposition) or MOVPE (metal-organic vapor phase epitaxy) processes [283]. The use of btsa complexes for the same purpose has appeared in the literature very recently [285]. Typical process conditions are shown in Scheme 14. It was found that the carbon contamination of the deposited metal is less in the btsa case. 

Chemical vapor deposition is an important technique in the production of all kinds of solid-state devices. In the process, the active metal organic vapor is swept into a two-dimensional sht reactor by a carrier gas, and deposition occurs at the hot top and bottom plates. The reaction at the plate surfaces can be written... 

Metal-organic vapor-phase epitaxy the same as MOCVD, but implying specific induced crystalline orientation of the deposited film... 

Creating metal oxide based advanced materials using lanthanide alkoxide complexes as molecular precursors is another area where the lanthanide alkoxide chemistry has found significant applications [5, 7-10]. A technique heavily used in the semiconductor industry for the growth of metal oxides materials is the process of metal-organic vapor chemical vapor deposition... 

The methods available for preparation of the different layers in thin-film solar cells include physical methods such as vacuum sputtering, vapor-phase deposition, and molecular beam epitaxy as well as chemical methods such as chemical vapor-phase deposition, metal organic vapor-phase epitaxy, chemical bath deposition (CBD), and electrochemical deposition (ED). This chapter explores the potential of electrodeposition as a route to the fabrication of absorber layers such as CdTe, CIGS, and CZTS for thin-film solar cells. Electrochemistry may also be usefiil for the preparation of transparent layers such as ZnO this topic has been reviewed by Pauporte and lincot [13]. 

Electrodeposition of semiconductors is a low-cost process. The most expensive equipment used in the process is a computerized potentiostat which may cost up to 5,000 compared to techniques like molecular beam epitaxy (MBE) or metal organic vapor phase epitaxy (MOVPE) in which the cost of the machines is in the order of 1 million. In addition, electrodeposition is versatile in application in the sense that many semiconductor materials can be electrodeposited using the same equipment. The only change required is basically the replacement of the deposition electrolyte by the desired one at any time. Evidence of a variety of electrodeposited semiconductors includes CdTe [32-42], CdS [10,32], ZnSe [11], ZnTe [12-14], SnS [17], CuInSea [18-22], CuInGaSe2 [23-27], and nitrides [9,43]. 

All the processes mentioned above are characterized by the fact that a support is treated with a suitable solution of the precious metal. An alternative preparation method in which a solid react with a metal precursor from the gas phase is metal-organk vapor deposition (MOCVD). In this process, a volatile metal organic precursor strikes the hot surface of the support. This contact leads to the immediate thermal decomposition of the surface with formation of a metal species on the support that can be further treated thermally, often under reducing gas atmospheres. 

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