Solution processing of YBa₂Cu₃O_7-x thin films

The aim of this work was to develop a non-vacuum chemical deposition technique for YBa₂Cu₃O_7-x (YBCO) coated conductors on rolling-assisted biaxially textured substrates (RABiTS). We have chosen the metal-organic decomposition (MOD) and sol-gel precursor routes to grow textured YBCO films. In the MOD process, yttrium 2-ethylhexonate, barium neodecanoate, copper 2-ethylhexonate and toluene were used as the starting reagents. YBCO films processed by the MOD method on SrTiO₃ (100) single crystal substrates were predominately epitaxial and consisted of c and a-axis oriented material. Films have a T_c,onset of 89 K and the best superconducting transition temperature of 63 K. Films pyrolyzed at 525 °C and subsequently annealed at 780 °C in a p(O₂) of 3.5×10^-4 atm contained YBCO phase predominately in a-axis orientation. In the sol-gel route, yttrium-isopropoxide, barium metal, copper methoxide and 2-methoxyethanol were used as the starting reagents. Sol-gel YBCO films on SrTiO₃ substrates were epitaxial and c-axis oriented.