SiO_2对SnO_2·CoO·Nb_2O_5压敏电阻非线性电学性质的影响

Effect of SiO_2 Addition on the Nonlinear Electrical Properties of the SnO_2·CoO·Nb_2O_5 Varistor System

对 Si O2 掺杂的 Sn O2 · Co O· Nb2 O5 压敏电阻非线性电学性质进行了研究 ,并对其微观结构进行了电镜扫描 ,且对其晶界势垒高度进行了测量。实验表明 x(Si O2 ) =0 .3%掺杂的 Sn O2 · Co O· Nb2 O5 压敏电阻的非线性系数 α高达 30 ,并且具有最高的击穿电场 (375 V/ mm)。采用 Gupta- Carlson缺陷模型对晶界肖特基势垒高度随Si O2 的添加而变大的现象进行了理论解释。

The effect of SiO 2 addition on the nonlinear electrical properties of the SnO 2·CoO·Nb 2O 5 Varistor System was investigated.The SnO 2·CoO·Nb 2O 5 varistor added with 0 3% SiO 2 has the nonlinear coefficient of α =30 and the highest breakdown electric field among the SiO 2 doped SnO 2·CoO·Nb 2O 5 varistor.To find the reason why the SnO 2·CoO·Nb 2O 5 varistor added with 0 3% SiO 2 has such a characteristic,the microstructures of the SiO 2 doped SnO 2·CoO·Nb 2O 5 varistors were examined,the voltage barrier height φ b at the grain boundaries for the SiO 2 doped SnO 2·CoO·Nb 2O 5 varistors were determined and the Gupta and Carlson defect model was considered.