The Improved Critical Currents of MOD-Processed YBCO Thick Films With ( : Ce, Zr) and YBa 2 SnO 5.5 Particles

We report the effects of barium-based perovskite particle inclusions of BaCeO 3 (BCO), BaZrO 3 (BZO), and YBa 2 SnO 5.5 (YBSO) on the thickness dependence of critical current density (J c ) in metal organic deposition (MOD)-processed YBa 2 Cu 3 O 7-δ (YBCO) films on the SrTiO 3 (STO) single-crystal substrate. With increasing film thickness, while BZO-doped YBCO films show a serious degradation in J c , caused by the interlayer at the boundaries of multicoated layers, BCO- and YBSO- doped films exhibit a significant enhancement of J c (77 K, self-field) over ~1 μm thickness even though BCO- or YBSO- doped YBCO films have degraded in-plane textures compared with undoped films, implying that these perovskite dopants affect not only the pinning properties but also the growth of multicoated layers. The highest critical current (I c ) value over 440 A/cm-width, corresponding to J c value of 1.8 MA/cm 2 , was obtained from the 2.4-μm-thick YBSO-doped film.