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The high Tc superconductors YBa2Cu3Oy: F were prepared from the mixtures of Y2O3, CuO, BaCO3 and BaF2, where the mixing ratio of BaCO3 and BaF2 was described as r=BaF2/(BaCO3+BaF2). Substitution of oxygen by fluorine in YBa2Cu3O7 caused the c-axis orientation in the composition range of r<0.2. Electrical resistivity of the samples annealed in O2 showed the two step drops; the first small drop at about from 150 to 250K and the second sharp drop to zero at 90K. However, the sample of r=0.4 showed the zero resistivity in the temperature range from 200 to 250K. All these samples showed the diamagnetism below 90K.