Study of electrical conductivity of barium titanate ceramics

Abstract

Abstract The electrical conductivity of barium titanate and 0.4% (mole) La doped barium titanate ceramics have been measured in the temperature range from 30 to 170°C with the help of a pA-meter at 10–90 V d.c. It is observed that doped ceramics give better positive temperature coefficient of resistivity (PTCR) effect than the undoped ceramics and by increasing voltage the PTCR region contracts for both types of the samples. The electrical conductivity at room temperature has also been measured using ramp and staircase voltages. It has been observed that by doping the room temperature electrical conductivity increases markedly by the order of 105. The electrical conductivity at room temperature of doped and undoped samples is larger and increases faster with voltage for the applied staircase voltages than that for the ramp voltages. Key Words: electrical conductivity ramp and staircase voltages positive temperature coefficient of resistivity