Dependence of the Intrinsic Conductivity Minimum of SrTiO 3 Ceramics on the Sintering Atmosphere

A shift of the intrinsic conductivity minimum of strontium titanate ceramics, which depends on the oxygen partial pressure of the sintering atmospheres, was observed. Different hydrogen partial pressures (at constant oxygen partial pressures) did not affect the minimum position. A comparison of the results with defect chemical calculations may explain this behavior as an oxygen partial pressure dependent formation of strontium vacancies showing acceptor character.