Ion-beam nanotexturing of buffer layers for near-single-crystal thin-film deposition: Application to YBa2Cu3O7-δ superconducting films

A method of producing biaxially textured template layers for near-single-crystal-quality film growth on substrates that do not provide a template for oriented crystalline growth is described and compared to existing methods. This technique, ion-beam nanotexturing (ITEX), produces a biaxially textured layer by oblique ion irradiation of an amorphous film surface. Using in situ reflection high-energy electron diffraction and ex situ x-ray diffraction, an yttria-stabilized zirconia (YSZ) template layer fabricated by ITEX is shown to have the appropriate surface texture for YBa2Cu3O7-δ coated conductor fabrication. A YBa2Cu3O7-δ thin film deposited on an ITEX YSZ layer has a critical current of 2.5×105 A/cm2 (77 K, 1 μV/cm). ITEX produces texture rapidly and should be ideally suited for future low-cost manufacturing.