Improvement of Critical Current in BiSrCaCuO Micropatterns by Oxygen Plasma Treatment

The influences of oxygen plasma on critical temperature and critical current density are studied using BiSrCaCuO micropatterns. Although a large critical temperature degradation as well as a slight decrease in a critical current is observed in 1.5–20 μm wide microbridges that have been put into an oxygen plasma, the critical temperatures are recovered by reducing excessive absorbed oxygen. Additionally, these recovered microbridges have higher critical current densities, whose improvement strongly depends on the microbridge width, 5–30 times than those without oxygen plasma treatment.