Growth quality and critical current density of sputtered YBaCuO thin films

✍ Scribed by W. Schauer; X.X. Xi; V. Windte; O. Meyer; G. Linker; Q. Li; J. Geerk

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 649 KB
• Volume: 30
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(90)90289-o

✦ Synopsis

Thin YBaCuO films have been deposited onto single crystalline substrates (AI203, MgO, SrTiO3, Zr(Y)O2) by inverted cylindrical magnetron sputtering. The growth quality of the films has been studied by X-ray diffraction and channelling experiments. Single crystalline growth has been achieved on (100) oriented substrates (MgO, SrTiO3, Zr(Y)O2) characterized by the occurrence of the channelling effect with minimum yield values, Xr, in, below 10% and narrow rocking curves (Aq' < 1°) in the diffraction experiments. Maximum critical current density values, lc, in zero field of 5 x 10 s, 2 x 106, and 9 x 105 A cm-2 at 77 K have been measured for films on SrTiO 3, Zr(Y)O2 and MgO, respectively. On randomly orientated AI203 and Zr(Y)O2 the films grow textured but are principally polycrystalline, resulting in depressed Jc values of 5 x 103 and 5 x 10 s A cm-2. With decreasing film thickness, d, high Jc values (2 x 106 A cm -2, 77 K) are observed down to d = 30 nm for films on SrTiO3. In ultrathin films (d = 5 nm) Jc degraded (e.g. 3.5 x 10 s A cm-2, 4.2 K) but revealed a magnetic field dependence quite different from that for thicker films. In particular, almost no depression of Jc was observed in a parallel field of up to 13 T.