Effects of Heat Treatment Conditions on the Critical Current Densities of Ba₂YCu₃O_7-y Films Prepared by the Dipping-Pyrolysis Process

Abstract

The effects of temperature and atmosphere on the BYCO formation reaction of BaCO 3 , Y 2 O 3 and CuO, prepared by the pyrolysis of metal acetylacetonate solution, were examined by TG-DTA, XRD and resistivity measurement. This reaction was found to proceed readily below 900°C under low oxygen partial pressures. Superconducting Ba 2 YCu 3 O 7- y films with T c,zero \cong90 K and J c (77 K)=300–400 A/cm 2 were prepared by the dipping-pyrolysis process using the above solution through heat treatments at 820°–880°C under controlled low oxygen partial pressures of ρ(O 2 )=1×10 -3 –2×10 -4 atm followed by O 2 annealing.