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The surface-oxidation-epitaxy (SOE) method promotes simple and cost-effective process to form a biaxially textured NiO template for epitaxial growth of YBa2Cu3Ox (Y-Ba-Cu-O) film. SOE tapes of 100 m in length were prepared by the reel-to-reel oxidation system with the tape moving speed of 10 m/h. A highly biaxially textured NiO layer, which had Δφ (full width at half maximum from X-ray φ-scan) of less than 23° throughout the whole length, was successfully formed under appropriate conditions of temperature and atmosphere. In order to improve surface conditions for obtaining high critical current density (Jc) for Y-Ba-Cu-O film on the SOE-tapes, we have investigated the effect of thin oxide cap layers such as MgO, SrTiO3, CeO2, and so on. When BaZrO3 was used as a cap layer, Jc and critical current (Ic) of Y-Ba-Cu-O films grown by the pulsed laser deposition (PLD) at 77 K were measured to be 1.3 MA/cm2 and 137 A, respectively. These values were for a 10 mm-width short tape. A continuous deposition of YBCO on 10-cm long ×10-mm wide SOE tape with SrTiO3 or BaZrO3 cap layer was also investigated. The end-to-end Ic was 1 A (Jc of 1.6 ×104 A/cm2) for SrTiO3 cap layer and 4 A (Jc of 5.6 ×104 A/cm2) for BaZrO3 one.