【摘要】 通过掺杂研究了微量Y2O3对低压氧化锌压敏电阻的电性能影响,并采用SEM测试手段对其微观组织结构进行了分析研究,从理论上探讨了Y2O3影响低压氧化锌压敏电阻电性能与组织的机理。研究结果表明,在0~0.07%(摩尔分数)掺杂范围内,随着Y2O3含量的增加,低压氧化锌压敏电阻的电场强度明显提高;当Y2O3含量超过0.07%时,电场强度又呈下降趋势。低压氧化锌压敏电阻掺杂Y2O3后,非线性指数α增大,漏电流IL减小,但当掺杂量在0.06%~0.09%(摩尔分数)的范围内,漏电流IL和非线性指数α的变化不大。其原因是Y2O3加入到氧化锌压敏电阻中,Y主要以固溶的形态分布于ZnO晶内和晶界处,使ZnO晶体的自由电子浓度增大,进而使填隙锌离子Zni的总浓度下降,引起填隙锌离子的传质能力下降,抑制了ZnO晶粒的生长,因而晶粒尺寸随Y2O3掺杂量的增加而减小。更多还原

【Abstract】 The effect of Y₂O₃ on electrical properties and microstructure of low voltage ZnO varistors was studied.The mechanism of the effect of Y₂O₃ was suggested based on theoretical analysis by using SEM.The results show that electrical field of low voltage ZnO varistors increased with the content of Y₂O₃ in the range of 0～0.07%（mole fraction）.But when the content of Y₂O₃ was more than 0.07mol%,the electrical field decreased with increasing Y₂O₃ content.The nonlinear coefficient（α） increased and the leakage current（I_L）decreased with increasing Y₂O₃ content,but when the content of Y₂O₃ was in the range of 0～0.06%,the variation of nonlinear coefficient（α） and the leakage current（I_L） was very small.The microstructure analysis indicates that the additive of Y₂O₃ lies inside ZnO grain and on the boundary,which leads to the decrease of the concentration of interstitial zinc,and then the size of ZnO grain decreases with the addition of Y₂O₃.更多还原