Growth and morphology of c-axis oriented Nd1.85Ce0.15CuO4−y thin films prepared by pulsed laser deposition technique

On the electron-doped superconductor of Nd2−xCexCuO4−y (NCCO) thin film, the presence of non-c-axis oriented grains, which are identified as (110) reflection peak at 2θ = 32.5∘ in the x-ray diffraction (XRD) spectrum is always observed. Meanwhile, high quality thin films without having impurities are necessary for device applications. We study the growth of NCCO thin film prepared by pulsed laser deposition technique and found that the volume fraction of (110) oriented grains depends on the laser fluence. With the laser fluence of around 2.2 J/cm2, NCCO thin film, which is free from the presence of non-c-axis oriented grains, could be obtained. The atomic force microscope images show that with the absence of (110) oriented grain the c-axis oriented grains grow into rectangular shape with a spiral growth mode. The rocking curve measurement for (004) peak give a full width at half maximum value of 0.12∘, which confirms the superior quality of the film and this film has superconducting critical temperature (Tc) at 21 K with a transition width (ΔTc) of 1 K.