Study on Electrical Conduction Mechanism of Mg-doped SrTiO_3 Ceramics

The dependence of the electrical conduction of Mg-doped SrTiO3 ceramics on the temperature and the oxygen partial pressure was discussed. The Mg contents in SrTiO3 were taken as 10mol%(sample 1), 20mol%(sample 2), 3Omol%(sample 3), 40mol%(sample 4) and 50mol%(sample 5), respectively. All samples were measured in the temperature range 20~900℃ and PO2 region from 3.8×10-4 to 1.2 × 10-1 atm. The results show that all samples exhibit p-type semiconduction.The factor m from R ∝ is dependent on temperature and Mg content in SrTiO3. The obtained results can be appropriately explained according to the X-ray diffraction patterns and the theory of defect chemistry.