The doping effects of transition elements on the PTC anomaly of semiconductive ferroelectric ceramics

Abstract

The influence of the addition of mainly 1st row of transition elements on the resistivity anomaly of BaTiO₃ semiconducting ceramics has been examined. The results showed that Mn ion is the most effective in increasing the PTC anomaly by up to a factor of 10⁹. The high temperature chemical behaviour of the ceramics was investigated. Discussions about the influence of Mn ion, its distribution and the nature of grain boundary phases on the formation of the ceramic structure adequate to the origin of the sharp PTC anomaly are given.