The growth mechanism and properties of Bi2212 thin films on miscut substrates by sol-gel method

Abstract

A sol-gel methodology is employed to prepare Bi2212 thin films on single crystal LaAlO3 miscut substrates with nominal tilt angles of 0°, 5°, 10°, and 15°. The study focuses on examining the phase purity, crystal structure, surface morphology, microstructure, and properties of these thin films. Experimental results indicate that the growth of Bi2212 thin films on miscut substrates proceeds through the step-flow mode using the sol-gel method. Higher tilt angles lead to an increase in the conventional resistivity of Bi2212 thin films. Tilted Bi2212 thin films exhibit a typical transverse Seebeck effect when comparing the resistivity in different directions. Notably, the Seebeck coefficient difference reaches 12 V/K when the substrate tilt angle is set at 15°. Meanwhile, tilted Bi2212 thin films consistently exhibit outstanding superconducting transition temperature (Tc) while demonstrating lower critical current density (Jc) values. These findings offer valuable insights for the development of Bi2212 high temperature superconducting thin films (HTSFs) in thermoelectric and superconductive devices, serving as a reference point for achieving optimal film characteristics.