ELECTRON-PARAMAGNETIC-RESONANCE STUDY OF TRANSITION-METAL-DOPED BATIO3 - EFFECT OF MATERIAL PROCESSING ON FERMI-LEVEL POSITION

We have studied the electron-paramagnetic-resonance (EPR) powder spect ra of transition-metal-doped BaTiO3 processed under oxidizing and redu cing conditions. From the EPR data a relative ionization-energy-level scale for the dopant species in BaTiO3 was established. These results along with a thermodynamic analysis that models the effects of tempera ture and oxygen partial pressure on the average charge states of dopan ts was used to provide a framework for understanding the role of mater ial processing on the Fermi-level position.