C-Axis oriented growth of magnetron sputtered YBaCuO thin films on MgO substrates

Abstract

Highly textured YBaCuO thin films were sputtered on MgO (100)-oriented single crystal substrates at ambient temperature followed by an anneal in oxygen for 1 h at temperatures up to 920~ X-ray diffractograms of the highly textured films indicate an orientation of the e-axis of the YBaCuO lattice perpendicular to the substrate surface. There are strong indications that the oriented caxis growth is due to a CuO self-flux effect. Auger measurements reveal a copper diffusion profile into the substrate down to a depth of more than 400 rim.

SCANNING AUGER MICROSCOPY AS APPLIED TO THE ANALYSIS OF HIGHLY TEXTURED YBaCu3Ox THIN FILMS

“…3(a). Form the linescan it has been determined that the depth of penetration of copper extends more than 400 nm below the YBaCuOMgO interface, in agreement with our earlier preliminary copper Auger linescan [9]. As can be seen from the line profile in Fig.…”

“…3(b), the main reason for reduced T, and quality of cuprate films on MgO is the copper loss into the MgO substrate. This on the one hand allows for wetting and oriented growth in sputter deposition [9] but on the other hand yields a copper loss, degrading the quality of the films. This is prevented in part by copper doping of MgO single crystals and by reduced annealing temperatures and times as shown by the currently prepared films.…”