本研究使用醋酸錫粉添加至商用鎳膏中做為MLCCs內電極材料製作MLCCs樣品，並經由改變錫的添加量及給予樣品不同再氧化條件，以釐清添加錫對於MLCCs之絕緣電阻衰退問題的影響。研究中發現添加錫會使得MLCCs樣品在燒結過程中於內電極生成微量Ni3Sn，改善內電極連續性，進而提升MLCCs樣品的電容值以及相對介電常數(K值)，但也會造成錫擴散進入鈦酸鋇使其晶粒成長，導致MLCCs樣品的電阻值及崩潰電壓下降。研究近一步表明，錫元素擴散進入鈦酸鋇應是在再氧化過程中以二價離子形式作為受體離子進入鈦酸鋇晶格，取代鈦位置並產生氧空缺，同時由於外界氧氣流入電極介面，與錫元素氧化產生之自由電子結合形成吸附氧，於電極介面形成肖特基能障，抑制漏電流產生，進而改善MLCCs樣品絕緣電阻衰退問題。另外，由於錫元素在氧化過程中會形成緻密氧化錫層，阻止內部錫元素繼續氧化，雖然提升氧化氣體之流量，但因錫元素氧化比例並未隨之上升，導致肖特基能障高度沒有顯著改變，因此不同再氧化程序對於MLCCs樣品之絕緣電阻衰退的影響並不明顯。

In this study, tin acetate powder was added to commercial nickel paste to serve as the internal electrode material for MLCCs, thereby creating MLCCs samples. By varying the amount of tin added and applying different re-oxidation conditions to the samples, this study aimed to elucidate the impact of tin addition on the insulation resistance degradation of MLCCs. The study found that the addition of tin leads to the formation of trace amounts of Ni3Sn in the internal electrodes during the sintering process. This enhances the continuity of the internal electrodes, thereby increasing the capacitance and relative dielectric constant (K value) of the MLCCs samples. However, this also causes tin to diffuse into the barium titanate, promoting grain growth, which in turn reduces the resistance value and breakdown voltage of the MLCCs samples. The study further indicates that during the re-oxidation process, tin diffuses into the barium titanate lattice as divalent ions, substituting for titanium and creating oxygen vacancies. Simultaneously, external oxygen infiltrates the electrode interface, combines with free electrons generated by the oxidation of tin to form adsorbed oxygen, thereby creating a Schottky barrier at the electrode interface. This inhibits leakage current and mitigates the insulation resistance degradation of the MLCCs samples. Additionally, during the oxidation process, tin forms a dense tin oxide layer, which prevents further oxidation of the internal tin. Although increasing the flow of oxidizing gas, the proportion of tin oxidation does not increase correspondingly, resulting in no significant change in the height of the Schottky barrier. Therefore, varying re-oxidation procedures do not significantly impact the insulation resistance degradation of the MLCCs samples.

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