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Tantalum ores often contain significant amounts of niobium, which is itself a valuable metal.As such, both metals are extracted so that they may be sold. The overall process is one of hydrometallurgy and begins with a leaching step; in which the ore is treated with hydrofluoric acid and sulfuric acid to produce water-soluble hydrogen fluorides, such as the heptafluorotantalate.
Mixed-metal thin-films have also been prepared from this compound. For example, lithium tantalate, LiTaO 3 , films are desirable for their non-linear optical properties and have been prepared by first reacting tantalum(V) ethoxide with lithium dipivaloylmethanate, LiCH(COC(CH 3 ) 3 ) 2 , to prepare a precursor suitable for metalorganic vapour ...
A productive overview is provided by several exceptional reviews covering fields of MOCVD such as, for instance, epitaxial growth of semiconductor compounds, [2] [3] [4] and low temperature deposition of metals. [5] [6] An overview of metal-organic compounds used for the MOCVD growth of different kind of materials is reported in the following ...
These metals can form useful silicides when deposited onto silicon. Mo, Ta and Ti are deposited by LPCVD, from their pentachlorides. Nickel, molybdenum, and tungsten can be deposited at low temperatures from their carbonyl precursors. In general, for an arbitrary metal M, the chloride deposition reaction is as follows: 2 MCl 5 + 5 H 2 → 2 M ...
In the metal organic chemical vapor deposition (MOCVD) technique, reactant gases are combined at elevated temperatures in the reactor to cause a chemical interaction, resulting in the deposition of materials on the substrate. A reactor is a chamber made of a material that does not react with the chemicals being used.
Physical vapor deposition (PVD), sometimes called physical vapor transport (PVT), describes a variety of vacuum deposition methods which can be used to produce thin films and coatings on substrates including metals, ceramics, glass, and polymers. PVD is characterized by a process in which the material transitions from a condensed phase to a ...
One-dimensional crystalline nanowires are then grown by a liquid metal-alloy droplet-catalyzed chemical or physical vapor deposition process, which takes place in a vacuum deposition system. Au-Si droplets on the surface of the substrate act to lower the activation energy of normal vapor-solid growth.
Copper metal ALD has attracted much attention due to the demand for copper as an interconnect material [citation needed] and the relative ease by which copper can be deposited thermally. [27] Copper has a positive standard electrochemical potential [ 28 ] and is the most easily reduced metal of the first-row transition metals.