Tantalum physical vapor deposition

Subsequent preliminary comparative studies of the behavior of an SiC based layer on Ta, Mo, Ti and steel substrates showed that better mechanical stability was obtained with a coating deposited on tantalum. This element was consequently considered to make PFCVD deposit/interlayer/steel stacks. Tantalum can be produced by physical vapor deposition (PVD), at variable thickness, with reproducible morphology. Note that preparation by chemical vapor deposition with or without plasma assistance (CVD or PECVD) is possible at low temperature but would require an optimization study in order to be compatible with the deposition conditions of the silicon carbide layer, the aim being to increase the mechanical stability. 

The copper films used in the experiments were prepared by electroless plating on a physical vapor deposited (PVD) tantalum film on top of a silicon wafer. The thickness of the copper and tantalum films was 1.5 pm and 300 A, respectively. Blanket tantalum films were also deposited by PVD on silicon to a thickness of 1000 A. The sanples used for static electrochemical... 

For carbide modification of graphite tubes (for a recent review see Refs. [183, 184], use is made of physical and chemical vapor deposition with metals such as Ta, W, Zr, etc., which leads to the formation of MC-coated graphite tubes or platforms. A solid layer of tantalum or niobium carbide can also be obtained as a result of treatment of the graphite furnace with large quantities of pure salts or a suspension of the element or its oxide in water however, this can lead to tubes with shorter lifetimes. Alternatively, the surface may be treated with aqueous [e.g. of Na2WC>4, (NH CriCb or ZrOCh] or alcoholic solutions of the salts of the elements mentioned. 

Substrate. Surface modifications were studied on tantalum pentoxide films deposited via physical vapor (ion plating)... 

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