ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 25, Number 4
JKCSEZ 25(4)
August 20, 1981 

The electrical conductivities of oxidized pure and Ni-doped SrTiO3 single crystals were measured as a function of the oxygen partial pressure(PO2) at temperature from 700 to 1200℃ and PO2 of 10-8 to 10-1 atm. Plots of log σ vs. 1/T at constant PO2 were found to be linear, and the activation energies obtained from the slopes of these plots have an average value of 1.34 eV for oxidized pure and 1.06 eV for oxidized Ni-doped SrTiO3 single crystals at PO2's between 10-8 to 10-1 atm. The log σ vs. log PO2 curves at constant temperature were found to be linear with an average slope of -1/5.6 ∼ -1/6.2 in the PO2 ranges. From the agreement between experimental and theoretically predicted values for the electrical conductivity dependences on PO2, an oxygen vacancy defect model was found applicable to oxidized pure and Ni-doped SrTiO3 single crystals over the temperature range, 700~1200℃. Conduction mechanisms were proposed to explain the dependences of electrical conductivity on temperature and PO2.