The anisotropy of O diffusion in this high-temperature superconductor was investigated by using off-axis thin films. High-quality oriented films with a thickness of 100nm, and with the c-axis inclined at an angle of up to 15º with respect to the normal to the film surface, were grown. The O diffusion which followed a small change in the ambient O partial pressure, at 200 to 400C, was monitored by means of in situ resistance measurements. The diffusivity was associated with an activation energy of 0.6eV, and the diffusion parameters decreased with increasing tilt angle. A comparison of the experimental data, with calculated values for an ideal monocrystalline film, suggested that the as-grown films consisted of crystalline grains having lateral dimensions of about 1μm.

Oxygen Diffusion in Off c-Axis Normal-State Bi2Sr2CaCu2O8 Films. A.Gramm, T.Zahner, U.Spreitzer, R.Rossler, J.D.Pedarnig, D.Bauerle, H.Lengfellner: Europhysics Letters, 2000, 49[4], 501-6