MIRROR-SMOOTH YBA2CU3O7-X SUPERCONDUCTING FILMS DEPOSITED BY PLASMA-ENHANCED PULSED-LASER DEPOSITION TECHNIQUE

Effect of microwave induced O-2- and Ar-plasma on characteristics of Y Ba2Cu3O7-x (YBCO) superconducting films deposited by pulsed laser depo sition technique (PLD) was examined. Surface roughness of the films wa s greatly improved at the presence of O-2-plasma, but was substantiall y degraded at the presence of Ar-plasma. Epitaxial-like YBCO supercond ucting films with c-axis perpendicular to the films' surface and with a- and b-axes aligned in films' plane were obtained on (100) MgO subst rates. They have onset of transition temperature at T-c = 90 K and zer o at T-c0 = 86 K. The mechanism for the improvement in this process wa s investigated by optical emission microscopy (OEM). The production of abundant atomic oxygen in microwave induced oxygen plasma that enhanc es the surface reaction kinetics is believed to be the main factor for improving surface smoothness of the films.