(Rb,Ba)Bi03 is a model material for the application of molecular beam epitaxy (MBE) to the growth of the superconducting perovskites. Synthesis of the superconducting phase can be accomplished in situ at temperatures between 300°C and 400°C, which has allowed the growth of superconducting films on silicon substrates. Measurements of the sticking coefficients for various growth conditions have shown that in a narrow region of flux compositions, adsorption and desorption rates of bismuth and rubidium (and possibly barium) will control the stoichiometry of the film. The epitaxy proceeds in the normal (1 0 0) orientation on [1 0 0) SrTiO3, despite a 10% lattice mismatch. On (10 0) MgO substrates, (1 1 0) epitaxy is obtained at lower substrate temperatures, while lattice matched (10 0) epitaxy occurs at higher substrate temperatures.
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