Liquid phase epitaxy of REBCO (RE=Y, Sm) thick films on YBCO thin film deposited on LAO substrate

By employing YBCO/LAO thin films as seeds, we succeeded in growing REBa2Cu3Ox (REBCO, RE=Y, Sm) thick films via the LPE method in air. Remarkably, a completely covered YBCO thick film with the c-axis orientation was achieved. Moreover, SmBCO LPE films were effectively induced by the YBCO/LAO thin films at a processing temperature of 1055°C, indicating that the YBCO/LAO thin film possesses a superheating property. Compared with the YBCO/MgO thin film, the YBCO/LAO thin film has a potentially higher thermal stability in LPE, due to its better lattice fitness at the film/substrate interface. On the other hand, compared to the thick films induced by NdGaO3 (NGO) substrates, YBCO/LAO thin-film-seeded thick films have the broad average spacing of about 150μm between adjacent cracks, almost five times wider than the former, which benefits the practical application in electronic devices. In short, the YBCO/LAO thin film becomes a third promising candidate for inducing REBCO LPE thick films, combined with conventionally used YBCO/MgO thin films and single-crystal NGO substrates. ► We firstly grew REBa2Cu3Ox (RE=Y, Sm) LPE films on YBCO/LAO thin films. ► Stability of YBCO/LAO in LPE process is potentially higher than that of YBCO/MgO. ► Adjacent crack spacing of LPE films on YBCO/LAO is as five times as that on NGO.