Current-Limiting Effect in Barium-Doped Indium Oxide Ceramics

A current-limiting effect (current saturation and even its decrease on voltage increase) was found in barium-doped indium oxide ceramics sintered at temperatures of 1473 K to 1573 K. For ceramic obtained at higher temperature (1673 K), current limiting was not observed. The results of electrical measurements, x-ray diffraction analysis, and scanning electron microscopy suggest that the electrical conduction in the material exhibiting the current-limiting effect was controlled by grain boundaries.