SEMICONDUCTIVE CERAMICS

摘要

A composition for example consisting of 5 to 95 mol% of bismuth oxide (Bi203) and 95 to 5 mol% of copper oxide (Cu20), or of 50 to 95 mol% of copper oxide (Cu20) and 50 to 5 mol% of manganese dioxide (MnO2), or of 5 to 95 mol% of bismuth oxide (Bi203) and 95 to 5 mol% of manganese dioxide (MnO2), is thermally diffused in the grain boundaries of semiconductor ceramics composed mainly of strontium titanate (SrTiO3) to form highly insulating layers in said grain boundaries to thereby provide semiconductive ceramics which have a reduced rate of change of dielectric constant with temperature, a reduced dielectric loss (tan .delta.) and increased insulating resistance relative to conventional barium titanate type semiconductor products.