LAUSR

Bi₂Sr₂CaCu₂O_8+δ (Bi-2212)/YBa₂Cu₃O _7−δ (YBCO) and YBCO/Bi-2212 heteroepitaxial bilayer films have been successfully prepared on LaAlO₃ (LAO) monocrystalline substrates by acetate based photosensitive Sol-Gel method. Two superconducting transition steps in the R–T curves of YBCO/Bi-2212 and Bi-2212/YBCO bilayer films were clearly observed. The first transition step has the superconducting critical transition temperature (Tc) of 90.1–90.8 K and the superconducting transition width (ΔTc) of 2–2.2 K, and these values correspond to the Tc and ΔTc values of YBCO single film. The second transition step has the Tc of 80–84 K and the ΔTc of 4.6–5.2 K, and these values correspond to the Tc and ΔTc values of Bi-2212 single film. XRD results showed that YBCO/Bi-2212 and Bi-2212/YBCO bilayer films grow heteroepitaxially with good in-plane and out-of-plane growth texture.