Effect of sputtering induced oxygen plasma on recovery of EuBa2Cu3Ox films

Activated oxygen plasma (AOP) annealing has been proposed as a recovery treatment in a decompressed oxygen atmosphere. As-sputtered EuBa₂Cu₃O₇ (EBCO) thin films with a T _c endpoint (T_ce) of 90 K were used for deterioration and recovery treatments. The removal and recovery for oxygen atoms was clarified from in-situ measurements of electrical resistance (R). The AOP annealing had a better recovery effect than pure oxygen annealing. AOP recovery conditions of annealing temperature (T _sa) of 450-700°C, plasma exposure and annealing time (t _p) Of more than 40 min, and oxygen pressure (P_O2ˇ(pc)) of more than 200 Pa were found to be appropriate. The AOP diffused around to the back side of a shutter, even one of 15 cm in radius, and diffused to a gap distance of 0.1 cm between the film and the shutter, restoring the degraded films to the high-quality characteristics