本研究選擇添加微量鈣離子和鋯離子於鈦酸鋇中，製備出單一相 (Ba0.95Ca0.05)(Ti0.97Zr0.03)O3 粉末 (BCTZ)，再額外加入碳酸鋇，使鈣離子取代至Ti-site，合成出單一相 (Ba, Ca)(Ti, Zr, Ca)O3 粉末 (BCTZC)。再以二階段燒結法控制晶界擴散和遷移，抑制晶粒成長現象，製備出微晶粒之陶瓷體。觀察添加微量鈣離子和鋯離子以及不同額外碳酸鋇添加量下，對於鈦酸鋇晶體結構、顯微結構和介電性質之影響。

由實驗結果顯示，可依序在煅燒條件為 1000oC - 4 h 和 1100oC - 4 h 下，合成出BCTZ 和 BCTZC 粉末。由XRD 和 Raman 分析可判斷粉末為正方晶相之結晶結構，隨著碳酸鋇添加量增加，發現c軸縮短，a軸伸長，正方性下降，晶格體積增加，以及自發極化量降低。

以二階段燒結法在不同燒結條件下試驗，可在 1250oC - 1 min - 1200oC - 8 h 和 1300oC - 1 min - 1200oC - 8 h 條件下獲得 BCTZ 和 BCTZC 陶瓷體，其晶粒大小可控制小於 0.5 μm 內，且相對密度達95 % 以上。其中 4Ba 系統，可於較低溫度以及較短持溫時間獲得完全緻密之陶瓷體。隨著額外添加碳酸鋇和晶粒大小之改變，於顯微結構上觀察到抑制晶粒成長的現象，於介電特性上發現，Tc 往室溫移動，To-t 朝高溫偏移；由於晶體內殘留之內應力影響，使 Tc 之介電常數被抑制，由於相轉換溫度移動以及晶粒減小導致，使得室溫之介電常數提升；整體而言，微晶粒陶瓷體其溫度-電容變化曲線有明顯寬化及平坦化的趨勢產生，歸因於晶體內殘留之高內應力以及正方性之降低，造成部分晶體相轉換為擬立方相，因而發生抑制自發極化之現象。

In this study crystal structure , microstructure and dielectric properties of (Ba0.95Ca0.05) (Ti0.97Zr0.03)O3 were investigate. Extra 4 mol % and 6 mol % BaCO3 were added into BCTZ powders to change the phase transition temperature via push Ca2+ from Ba-site to Ti-site. As the results, single phase BCTZ powder could be obtained when calcined at 1000oC for 4 h. BCTZ powder with extra BaCO3 could be obtained after calcined at 1100oC for 4 h. The crystal structures of both are tetragonal phase confirmed by XRD and Raman spectrums. Moreover, the experimental results showed a - axis increased, c - axis decreased and tetragonality decreased. It also enlarged the volume of unit cell and reduced the spontaneous polarization.

To use two-step sintering method to control grain boundary diffusion and migration to prepare submicro-grain ceramic. BCTZ and 4Ba sintered bulk were successfully fabricated at 1250oC - 1200oC - 8h and 6Ba sintered bulk were successfully fabricated at 1300oC - 1200oC - 8h. The bulk density were more than 95% of the theoretical density and the grain size was controlled less than 0.5 μm.

As the extra BaCO3 content increased, the Tc moved to room temperatures nonlinearly, To-t shift toward high temperature and the Curie peak was suppressed. Due to ionic substitution and submicro-grain ceramic, it can lead to a high internal stress in the microstructure and reduce the tetragonality and spontaneous polarization. It may suppose that formation of a pseudo-cubic perovskite in the BCTZ, 4Ba and 6Ba unit cell, therefore, broadening and flattening the Temperature Coefficient of Capacitance curve.

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