ZnO压敏陶瓷中的本征缺陷

研究了ZnO-Sb₂O₃-BaO系和ZnO-Bi₂O₃-Sb₂O₃-BaO系压敏陶瓷的介电损耗因子D(tanδ)与频率f的关系。发现不含Bi₂O₃试样在室温附近出现一新的损耗峰,峰值频率在2MHz左右,对应的电子陷阱能级为0.18eV,分析认为是由于本征缺陷Zn_i所致。设想Bi离子对Zn_i 关键词：

INTRINSIC DEFECTS IN ZnO VARISTOR CERAMICS

The relationship between dielectric loss factor D (tanδ) and frequency for ZnO-Sb₂O₃-BaO and ZnO-Bi₂O₃-Sb₂O₃-BaO varistor ceramics has been investigated. A new dielectric loss peak was found near by 2MHz at room temperature for the sample in the absence of Bi₂O₃, the corresponding electron trapping level was about 0.18 eV, it was considered that the loss peak resulted from intrinsicdefect Zn_i . It was assumed that the formation of intrinsic defect Zn_i was restricted by ion Bi, it was consistent with experimental fact that the degradation properties of varistor ceramics under the long duration load voltage are improved with the increasing amount of Bi₂O₃.