Superconducting lead films have been synthesized using an electroless plating technique on a number of different substrates, including copper, silicon and sapphire and superconducting thin films of magnesium diboride has been synthesized on copper substrates using a novel electroless plating technique. X-ray diffraction (XRD) measurements confirm that the films are lead with lead oxide impurities, and scanning electron microscope (SEM) images show that the films prepared on copper are uniform. However, samples deposited on silicon and sapphire exhibit pronounced structural irregularities. The Pb films deposited on a copper substrate have a superconducting volume fraction of approximately 45%, while the superconducting fraction for films on silicon and sapphire is on the order of 1%. We attribute this lower superconducting fraction to the presence of lead oxide impurities and structural defects in the samples. X-ray diffraction measurements confirm that the films are crystalline MgB2 with some impurity phases, including MgB4 and Mg 2B2O5. Clear evidence for a superconducting transition in the magnetization measurements was observed.
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