本研究探討低溫燒結積層氧化鋅變阻器所需之粉體配方及熱處理條件；以V2O5為電性成型劑，並以氧化錳、氧化鈷及其他氧化物做為電性修飾劑，探討各添加劑扮演的角色，及其對氧化鋅電特性之影響。同時，本研究亦探討粉體之熱處理條件對氧化鋅低溫共燒之影響。
由本研究的結果可知，V2O5確實可使ZnO變阻器以900℃之低溫來完成燒結；另外，適當地延長燒結時程亦可得到更低溫的燒結溫度，若同時搭配夠小之ZnO粒徑的話，將使得內外電極及陶瓷體共燒的可能性更大。粉體配方以Mn3O4添加量為0.3mol%、CoO添加量為0.5mol%及Bi2O3添加量為0.1mol%時可得到較佳的α值(24)及最低之漏電流值(2μA)。實驗過程中亦發現粉體之熱處理過程關係到V2O5系統之ZnO變阻器能否保持積層化產品燒結後的狀態，未經熱處理或是不當的熱處理將使得共燒之內電極收縮過大甚至消失；結果顯示熱處理溫度約350~400℃並配合較長之熱處理時程(4小時以上)，將可改善內電極與陶瓷共燒後的狀態。

In this thesis, the powder formation and thermal treament parameters for low temperature firing of zinc oxide(ZnO) based multi-layered varistors are studied. Vanadium oxide(V2O5) was used as electrical former, and manganese oxide(MnOx), coblt oxide(CoOx) and other additives were used as electrical modifiers. The object of this thesis is to investigate the effects of additives on the electrical characteristics of ZnO varistors. Meanwhile, the parameters of thermal treament process of raw materials on the effects of low temperature cofiring of ZnO varistors are also studied.
As a result, we found that V2O5 can lower the sintering temperature of ZnO-based varistor as low as 900℃. Forthuremore, prolonged sintering duration and reduced ZnO particle size might lower the sintering temperature futher to a given temperature which makes it possible to co-fire the ceramic body, inner electrodes and outer electrodes. The formulation of powder with added 0.3mol%Mn3O4, 0.5mol%CoO and 0.1mol%Bi2O3 can obtain a high αvalue of 24 and leakage current of 2μA. Besides, we also found that the thermal treament of powder can affect the shrinkage or diffusion of inner electrodes in multi-layered ZnO varistor shape dramastically. Without thermal treament or inproper thermal treament conditions will cause the inner electrode over-shrinkaged or even disppeared. According to the results of experiment, 350~400℃and a longger period (4 hours and above) will improve the phenomenon of over -shrinkaged.

誌謝 i
摘要 ii
目錄 v
圖表目錄 vii
第一章 前言 1
1.1 研究背景 1
1.1.1 ZnO變阻器介紹 1
1.2 研究動機 3
第二章 基礎背景 5
2.1 變阻器理論基礎 5
2.1.1 ZnO變阻特性形成機制 5
2.2 粉體配方 5
2.2.1 電性成型劑系統與V2O5介紹 5
2.2.2 電性修飾劑 8
2.3 積層式陶瓷元件製造流程介紹 9
第三章 實驗步驟與方法 11
3.1 粉體配方部份 11
3.1.1 MnOx及CoOx價數對電性之影響 11
3.1.2 燒結條件 12
3.1.3 其他電性修飾劑 12
3.2 粉體熱處理部份 13
3.2.1 煅燒溫度 13
3.2.2 煅燒時程 14
第四章 結果與討論 15
4.1 粉體配方部份 15
4.1.1 MnOx及CoOx價數對電性之影響 15
4.1.2 燒結條件 17
4.1.3 其他電性修飾劑 17
4.2 粉體熱處理部份 19
4.2.1 煅燒溫度 19
4.2.2 煅燒時程 19
第五章 結論 21
參考文獻 23

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