Abstract
The electrical conduction mechanism of (Ba0.5,Sr0.5)TiO3 as a function of temperature was studied. Au/BST/Pt metal-insulator-metal (MIM) capacitors were used. The temperature range is from 300 to 423 K. The BST films were deposited by rf magnetron sputtering. The electrical conduction current depends on the voltage polarity. At high electrical field (>800kV/cm) and with the Pt electrode biased negative, the Pt/BST forms an Schottky barrier with a barrier height of 0.58eV in the temperature range from 300 to 373 K. The Au/BST interface forms an ohmic contact. The conduction current with the Au electrode biased negative shows space-charge-limited-current (SCLC) behavior. A possible energy band diagram is proposed to explain the experimental results.