Structure and phase composition of niobium-copper deposited films

Abstract

Solid solutions of Nb + 9 at % of Cu and Cu + 12 at % of Nb are obtained by ion plasma sputtering and the codeposition of ultrafine particles of niobium (less than 11 nm) and copper (less than 1.7 nm), which is confirmation of the theory of the thermal fluctuation melting of small particles and the coalescence of quasi liquid clusters of subcritical size. The film coating consists of an amorphous phase in the concentration range 22.7-80.2 at % of Cu. Upon the annealing of amorphous systems of all compositions at 600-850°C, a new phase, presumably, of an orthorhombic system is found and its approximate lattice parameters are deter mined. At specific dimensional ratios of ultrafine particles of niobium and copper, nanoclusters with an ordered superlattice are formed. The appearance of a superstructure is a result of the size factor.

Technology of Porous Tantalum Production

“…The concentration of deposited metals was verified by the weighing method, i.e. the amounts of each metal sputtered and deposited during the formation of coating were determined [3]- [6]. The film thickness was determined by Rutherford proton back-scattering spectrometry using UKP-2-1 tandem accelerator in the Institute of Nuclear Physics (Republic of Kazakhstan) and was calculated using the amounts of deposited metals.…”

“…The authors find it tempting to find an alternative method of preparing a porous refractory metal in the coating using the technique of magnetron sputtering with two magnetrons [3]- [6]. For this purpose, the most promising seems the preparation of a mixture of refractory metal (tantalum) with metal characterized by high vapor pressure at a relatively low temperature, cadmium.…”