Preparation of YBCO superconducting thick films On MgO substrates by modified melt growth process

TL;DR

This paper reports a novel modified melt growth method for fabricating 200-300μm thick YBCO superconducting films on MgO substrates, achieving high critical temperature and current density with detailed microstructural analysis.

Contribution

It introduces a new approach for preparing thick YBCO superconducting films using a sandwich structure and modified melt growth, improving film quality and superconducting properties.

Findings

Critical temperature of 87.3K achieved.

Critical current density of 2.78 x 10^3 A/cm² at 77K.

Microstructure shows Y123 matrix with Y211 inclusions.

Abstract

Superconducting thick films (200$\mu$m-300$\mu$m) of YBCO have been fabricated successfully on MgO substrates by a new approach. The precursor powders (YBa2Cu3O7-$\delta$(Y123)+0.1molY2BaCuO5(Y211)) are placed between two MgO (10mm x 10mm) slices to form sandwich structure. The YBCO thick films have been obtained from the precursors by modified melt growth process. Resistance measurements of YBCO thick films show Tcon of 87.3K and $\Delta$T of 4.5K. Estimates using hysteresis loops and the Bean model give a value of 2.78 x 10$^{3}$ A/cm2 (77K, 0T) for the critical current density. The observations of scanning electron microscopy (SEM) and x-ray diffraction patterns (XRD) show the supercoducting Y123 phase matrix containing discrete Y211 inclusions. Keywords: superconducting thick films, YBCO, Y211 phase, peritectic temperature