In situ pulsed laser deposition of Nd1.85Ce0.15CuO4−y

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Abstract
Thin films of the electron‐charge‐carrying high‐temperature superconductor, Nd1.85Ce0.15CuO4−y have been deposited by pulsed laser deposition on to 〈100〉 MgO and SrTiO3 substrates. Film composition, structure, and transport properties were measured as a function of deposition conditions (substrate temperature, oxygen deposition pressure, and postdeposition annealing conditions). C‐axis oriented, single‐phase films were formed at high substrate temperatures (900 °C) in high background pressures of oxygen (200 mTorr), but were semiconducting when quenched to room temperature in either oxygen or nitrogen. A reduced oxygen background pressure during deposition at 900 °C resulted in films that were transparent and insulating due to the loss of copper. Films which were deposited at 900 °C (Poxygen≥200 mTorr) and then slowly cooled in a vacuum were superconducting with a maximum Tc (onset) of 15 K and Tc(R = 0) of 11 K.