本研究主要探討煆燒處理對國巨X5R及X6S介電陶瓷之微結構、晶體結構以及介電性質等之影響。實驗透過XRD、SEM、TSDC、XPS、交流阻抗及介電性質量測等方法來分析煆燒處理(800, 900, 1000°C)對於X5R及X6S介電陶瓷微結構、核殼結構的完整性、晶粒、晶界電阻及導電活化能之影響。結果發現在TCC曲線的高溫端經1000°C煆燒處理後之樣品，比起無煆燒之樣品明顯平緩許多，可符合X5R或者X6S規格。晶體結構隨煆燒溫度提高其正方性逐漸變小，顯示具立方相殼區之比例提高，四方相核區之比例下降，證實煆燒對形成核殼結構有一定的影響。此外在交流阻抗圖譜分析中發現，隨煆燒溫度上升，樣品之阻抗值均明顯比無煆燒組來得高。隨著煆燒溫度的上升，其晶粒及晶界之導電活化能均增高。存在於胚體中之氧空缺濃度及Ti3+相對含量，均隨著煆燒溫度上升，呈現下降的趨勢。並進一步以熱刺激退極化電流分析，隨著煆燒溫度的上升，可以觀察到去極化電流有明顯下降的趨勢，證明其氧空缺濃度確實隨著煆燒溫度上升而下降。因此推論煆燒效應可使受體元素如Mn2+等先佔據在B位，促使後添加之兩性元素Dy在燒結過程佔據A位，作為施體並產生電子補償，但當再氧化過程時，因氧分壓上升，使其電荷補償機制轉為鋇空缺離子補償，使氧空缺濃度下降，並在晶界形成蕭特基能障，因此提升其絕緣電阻及降低其熱刺激退極化電流。

This study investigates the effects of calcination on the microstructure, crystal structure and dielectric properties of X5R and X6S dielectric ceramics from Yageo. The effects of calcination (800, 900, 1000°C) on the microstructure, core-shell structure, grain size, grain boundary resistance and conductivity activation energy of X5R and X6S dielectric ceramics were analyzed by XRD, SEM, TSDC, XPS, AC impedance and dielectric properties measurements. It was found that the orthogonality of the crystalline structure gradually decreased as the calcination temperature increased, showing an increase in the proportion of cubic phase shell region. With the increase of calcination temperature, the conductivity activation energies of the grain and grain boundary increased. With the increase of calcination temperature, the depolarization current decreased significantly, which proves that the oxygen vacancy concentration really decreased with the increase of calcination temperature. As a result, the calcination effect is inferred to cause acceptor elements such as Mn2+ to occupy the B-site first, and then the added amphoteric element Dy occupies the A-site during the sintering process, acting as a donor and generating electron compensation. Due to the increase in oxygen partial pressure during the reoxidation process, the charge compensation mechanism is changed to barium vacancy compensation. As a result, the oxygen vacancy concentration decreases and a Schottky barrier forms at the grain boundary, increasing insulation resistance and decreasing thermally stimulated depolarization current.

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