摻雜對鈦酸鋇陶瓷的微結構與介電性質之影響

The effects of dopants on the dielectric properties and microstructure of barium titanate ceramics

連聖豪(Shen-Hao Lian)

指導教授 ： 王錫福 ； 王玉瑞

國立臺北科技大學/工程學院/資源工程研究所/碩士(2011年)

摘要

鈦酸鋇陶瓷是目前應用最廣泛的電子陶瓷材料之一，以其做為基材的產品眾多，例如電容器、溫度感測器、熱敏電阻器、壓電材料感測器、致動器、能量交換器等元件。適當摻雜添加劑可改善介電性質、提升燒結性質、降低介電損失、抑制介電峰值、或使居理溫度偏移並符合EIA標準中的X8R規範，規範中其介電常數>2000與介電損失<2.0%，溫度電容變化率小於正負15%。
本實驗使用氧化銦、氧化鑭、氧化釔、氧化釹等四種元素來添加在以鈦酸鋇為基材的混合物中，來研究因添加量與不同溫度對介電溫度曲線的影響，綜合四個系統的實驗結果，添加氧化鑭與氧化釔在適當的添加量與燒結溫度中可符合X8R規範，氧化鑭添加1mol%在1325℃的燒結溫度下，介電常數約2584介電損失約1.78%，氧化釔添加1mol%在1325℃的燒結溫度下，介電常數約2012介電損失約0.68%，為本實驗中最佳性質，並符合X8R規範。

關鍵字

鈦酸鋇 ； X8R ； 積層陶瓷電容

並列摘要

Barium titanate ceramics can be applied extensively in electrical ceramic materials. Barium titanate ceramics can be used in various productions, such as capacitor, temperature sensor, thermistor and piezoelectric sensor, actuators and energy converter. Appropriate doping can improve dielectric properties, reduce sintering temperature and dielectric loss, smooth dielectric curve, shift curie temperature and to conform the X8R standard of EIA with dielectric constant > 2,000, dielectric loss < 2.0% and TCC < ±15%.
In this thesis, barium titanate ceramics is add with different proportion of In2O3, La2O3, Y2O3, Nd2O3. The effect of different additive ratio and the sintering temperature on dielectric temperature curve were interstigated. Experimental result reveals that the BaTiO3 with 1 mol% La2O3 additive were sintered at 1325℃, the dielectric constant reaches about 2584, dielectric loss reaches about 1.78% ; the BaTiO3 with 1 mol% Y2O3 additive were sintered at 1325℃, the dielectric constant reaches about 2012, dielectric loss reaches about 0.68%, and the TCC of both samples are smaller than ±15%.

並列關鍵字

BaTiO3 ； X8R materials ； MLCCs

參考文獻

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