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Lithium coatings on various substrates have numerous applications: Boron neutron capture therapy, neutron activation analysis, super‐conducting tokamak etc. Traditionally these coatings are produced by well‐known techniques such as electrochemistry and evaporation. In this work, we investigated a new method based on sputter‐evaporation, which enables thick coatings (>10 µm) to be built on various substrates within a short timeframe. In order to minimize the process time, evaporation techniques can be used but the coating quality suffers. Moreover, it is well known that the use of DC magnetron sputtering results in the deposition of good quality coatings (smoothness, density, adhesion); however, the deposition rate is low. The rationale of this work is to combine these two techniques, yielding a sputter‐evaporation process that possesses the advantages of each separate technique. Li is placed in a stainless steel crucible (cathode), and heated by the plasma generated by a magnetron discharge. The Li temperature is measured by a thermocouple welded onto the cathode and measured at different plasma power densities. The deposition rate of lithium is measured using a quartz balance and by profilometry, at several temperatures (from 0 to 580 °C). Li samples were depth‐profiled with the resonant nuclear reaction 7Li(p,γ)7. In addition to the concentration, certain characteristics like the density and the chemical reactivity of layers, are also important. Thus we have studied the evolution of the density with time, estimated by weight and profilometry measurements, and the change in morphology, by cross‐sectional scanning electron microscopy (SEM), of samples exposed to air at room temperature. The evolution of the film compounds have also been determined by X‐ray powder diffraction. These physical properties have been investigated for various bias substrates during deposition.

The chemical interactions between Bi 2 Sr 3 CaO 7 (Bi-2310) and Bi 2 Sr 2 Ca 0.8 Dy 0.2 Cu 2 O 8 (Bi-2212(Dy)) at 965°C were investigated by means of: (i) an interdiffusion couple and (ii) layers deposited by dip coating on oxidized nickel substrates. The samples were characterized by optical and electron microscopies, energy-dispersive x-ray (EDX) analysis and x-ray diffraction. It turns out that at the peritectic temperature of Bi-2212(Dy), the Bi-2310 phase reacts with the liquid phase resulting from the peritectic decomposition of the Bi-2212(Dy) phase. Dissolution of Bi-2310 leads to an enrichment in Sr and an impoverishment in Cu of the liquid phase, resulting in a shift of the composition of the insoluble phase towards the Ca-rich end of the (Ca, Sr)O solid solution.