Effect of annealing temperature on the structural-microstructural and electrical characteristics of thallium bearing HTSC films prepared by chemical spray pyrolysis technique

Abstract

In order to get good quality reproducible films of Tl : HTSC system, we have studied the different annealing conditions to finally achieve the optimized annealing condition. In the present investigation, Tl-Ca-Ba-Cu-O superconducting films have been prepared on YSZ (100) and MgO (100) single crystal substrates via precursor route followed by thallination. The post deposition heat treatments of the precursor films were carried out for various annealing temperatures (870°C, 890°C) and durations (1 and 2 min). The optimized thallination procedure occurred at 870°C for 2 min into good quality films with T c (R = 0) ~ 103 K for YSZ and T c (R = 0) ~ 98 K for MgO substrates, respectively. Further we have correlated the structural/microstructural characteristics of the films.

Microstructure dependent microwave properties of spray deposited Tl–Ba–Ca–Cu–O films

“…The better connectivity was seen in samples after intercalation of thallium into sample after primary heat treatment. This connectivity of the sample is essential for the superconducting transition temperature and critical current densities [11,12], which in turn affects the microwave properties as the current density of sample increases the surface resistance (R s ) decreases.…”

The Role of Cooling Condition on the Superconducting Properties of Tl<sub>2-x</sub>Hg<sub>x</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>10+δ</sub> System

“…The solid state reaction technique has been used to prepare homogeneous and well-defined single phase superconducting samples with uniform oxygen stoichiometry evolution of accurate physical parameters. Solid state reaction is the least expensive and largest batch size of any powder fabrication process, the procedure involves a simple blending of the required precursors, followed by one or more reactions at a high temperature [10].…”