CaCu3Ti4O12(簡稱CCTO)是一種特別的介電陶瓷材料，其結構為鈣鈦礦立方晶結構。此材料特殊之處在於擁有極高的介電常數，如在室溫下可高達104~105，此外在廣泛的溫度範圍100K到600K間，其介電常數幾乎維持一定。但當溫度降至100K以下時，介電常數立即落降至約100。
本研究為探討添加MnO2和試片表面不同電極對CCTO介電和顯微結構的影響。可以發現錳的摻雜會降低CCTO的介電常數，另外由添加矽的CCTO其等效電路中，有包含晶域、晶域邊界、晶界、電極的存在。

An unusual dielectric ceramic material CaCu3Ti4O12 (CCTO) is a cubic perovskite structure. It possesses an extraordinarily high dielectric constant at room temperature of about 104~105. Besides, the dielectric constant is nearly constant over a wide temperature range ~100-600K. However the dielectric constant drops rapidly to 100 below about 100K.
In this study, we would discuss the influence of MnO2 addition and electrode difference on the dielectric behavior and microstructure of CCTO. We can find that manganese doping would decrease the dielectric constant of CCTO. In addition, an equivalent circuit of CaSiO3-CCTO including domain, domain boundary, grain boundary, and electrode contact is proposed.

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