High-temperature resistivity measurements of YBa2Cu3O7-δ doped with sulphur

The diffusion of sulphur into YBa2Cu3O7-delta using an open tube technique operating between 450 and 650 degrees C is demonstrated. The resulting material has unchanged low-temperature characteristics but high-temperature resistivity measurements indicate that the sulphur plays a role in suppressing the out-diffusion of oxygen prior to the transition between the orthorhombic and tetragonal phases. This diffusion technique and the inclusion of sulphur generally may have a use in widening the super conductor processing temperature range without a phase change and in reducing the out-diffusion of oxygen which can be a problem in device structure fabrication. (C) 1999 Elsevier Science Ltd. All rights reserved.