Abstract
The annealing effect on the resistivity and the critical temperature of BiSrCaCu2Oy where the low temperature phase is predominant was examined. The resistivity becomes higher, as increasing the annealing temperature in N2 atmosphere and the sample annealed above 700°C did not show zero resistance from 20 K to 300 K. However, the resistivity and the critical temperature recover nearly the same value as the as-grown sample after annealing in O2 atmosphere.