近年來鈦酸鋇粉體之研究隨著積層陶瓷電容器 ( Multilayer ceramic capacitor, MLCC) 之蓬勃發展變得愈來愈重要，欲使鈦酸鋇達到高電容且同時具備穩定的溫度-電容變化曲線，添加適當的元素或化合物作為添加劑的選擇及研究就變得重要。除了添加劑的選擇外，使用傳統固相反應法在純度、均勻性及粒徑分佈上皆不如化學沉澱法，但在成本考量上，固相反應法仍具有其優勢。
因此，本研究乃希望透過改善固相反應法混合不均勻之缺點，利用尿素沉澱法作為製程方法，硝酸鎂 (0.5 mol%) 及硝酸釔 (2.0 mol%) 作為添加劑，選擇先披覆鎂再披覆釔並探討尿素沉澱法對於本系統之最佳實驗參數，並於得到高緻密陶瓷體後，對燒結行為、顯微結構及介電常數做探討。
本研究之結果顯示，以尿素沉澱法披覆鎂於鈦酸鋇上，需於90oC之環境下，尿素添加倍率一倍，持溫24小時後，經由煅燒900oC持溫3小時，形成鈦酸鋇鎂之固溶體。之後再以尿素沉澱法披覆釔於鈦酸鋇鎂固溶體上，需將尿素添加倍率增加為30倍，產率才可達相對理論產率的 90% 以上，並於1250oC、1300oC持溫3小時之燒結條件下，發現核殼結構的存在，使溫度-電容變化曲線 (TCC) 平坦化，並與固相反應法做比較，使用尿素沉澱法具有正面的幫助。

This study investigates the effects of doping barium titanate with magnesium and yttrium using a urea-precipitation method. In this approach, magnesium oxide and yttrium oxide are synthesized and coated on Barium titanate core powder using the urea-assist reaction of magnesium nitrate and yttrium nitrate. It turns out that the reaction yield can be high when the reaction is performed at 90°C for 24 hours. Barium titanate powder coated with yttrium needs more urea. The magnesium oxide can be seen after calcination at 900°C, and forms a coating layer of barium titanate. The core–shell structure can be obtained in Barium Titanate ceramics that are co-coated with magnesium oxide and yttrium oxide upon sintering at 1250°C and 1300°C for 3 h. The TCC curve can also be flattened. This precipitation method is more helpful than the solid reaction method.

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