• Critical current density;
  • Cu tape;
  • HPCVD;
  • MgB2 film;
  • SiC-impurity layer


The influence of SiC-impurity layer and growth temperature on microstructure and superconducting properties are studied for MgB2 superconducting tapes. A pulsed laser deposition (PLD) system is used for the deposition of amorphous SiC-impurity layers on flexible metallic Cu(001) tapes. The MgB2 superconducting tapes are fabricated by growing MgB2 films on the top of SiC/Cu tapes, over a wide temperature range of 460–600 °C, by using hybrid physical (HP) CVD system. Among all tapes, the MgB2/SiC/Cu tape deposited at a temperature of 540 °C has the highest Tc of ∼37.7 K. Scanning electron microscopy (SEM) images reveal hexagonal-shaped MgB2 grains with good connectivity, and their sizes are found to vary with growth temperature. When compared to MgB2/Cu tapes, the MgB2/SiC/Cu tapes exhibit an opposite trend in the dependence of critical current density (Jc) with deposition temperatures. The improved Jc(H) behavior can be explained on the basis of the enhanced flux pinning force density (Fp) for MgB2/SiC/Cu tapes upon increasing the growth temperature