本研究利用固態反應法製作氧化鋅變阻器，探討添加過渡金屬氧化物及 Sr(Co,Nb,Ta)O3 對 ZnO 變阻性質之影響。結果證實於 ZnO 中添加適量過渡金屬氧化物及 Sr(Co,Nb,Ta)O3，可有效提高其變阻性質，α 值可達65 及崩潰電壓可至 4000V/mm，同時漏電流降低至0.67μA/cm2。同時添加具有良好氧離子導電度之鈣鈦礦結構 Sr(Co,Nb,Ta)O3與過渡金屬氧化物 Co3O4、Mn3O4於 ZnO 中，當降溫時氣氛中之氧藉由位於晶界上具有良好氧離子導電度之 Sr(Co,Nb,Ta)O3沿著晶界擴散至晶粒表面，此時富集於晶界之過渡金屬離子 Mn 及 Co 被氧化，失去電子，促進氧在 ZnO 晶界上化學吸附形成介面陷阱，進而提高 ZnO 之變阻性質。

In this study, ZnO varistors were prepared using the solid-state reaction method, and the effects of the addition of Sr(Co, Nb, Ta)O3 and transition metal ions on the microstructure and varistor properties were investigated. The ZnO varistors with a breakdown voltage of 4000V/mm and nonlinearity coefficient of 65 were obtained by co-doping of Sr(Co, Nb, Ta)O3 and transition metal ions. The addition of Sr(Co,Nb,Ta)O3 with excellent oxygen ion conductivity and transition metal ions can effectively promote the adsorption of oxygen at the grain boundary during the cooling process. The oxygen diffused to the grain boundaries of ZnO through Sr(Co, Nb, Ta)O3 at the grain boundary. The transition metal ions were oxidized and lose electrons, which resulted in the oxygen molecules chemically adsorbed at the grain boundary to form more interface traps. The addition of Sr(Co, Nb, Ta)O3 and transition metal ions into ZnO can significantly improve the varistor properties.

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