目前市面上的多層陶瓷電容為求降低生產成本，多以卑金屬材料作為電極。鈦酸鋇陶瓷為了避免電極氧化而必須在還原氣氛下燒結，因此容易出現半導化的現象，造成整體絕緣電阻下降。為了改善此現象，可以藉由添加低價離子去取代高價離子，形成受體補償以抑制半導化現象。
本研究使用固態反應法合成出鎂摻雜鈦酸鋇Ba(Ti1-xMgx) O3-x之介電材料，藉由不同添加量之鎂離子取代鈦酸鋇中Ti的位置，了解鎂離子進入鈦酸鋇Ti位置後，對晶體結構、晶格參數、拉曼光譜、比表面積、顯微結構以及介電性質之影響，進而探討此材料在積層陶瓷電容應用之可行性。
實驗結果顯示，將Ba( Ti1-xMgx) O3-x (x = 0、0.01、0.03) 粉末透過二階段煅燒可以成功合成出無二次相之鎂摻雜鈦酸鋇粉末，再透過Rietveld refinement精算得知，當Mg2+進入鈦酸鋇後，單位晶格內的a軸會伸長、c軸會縮短，造成正方性下降，並使晶格體積上升，此部分結果與文獻[1]中，Mg2+進入Ti位置之結果相符合；拉曼光譜分析中，所有tetragonal phase之特徵峰強度也下降且寬化，此現象表示鈦酸鋇由tetragonal phase漸漸轉變為cubic phase，此結果與Rietveld refinement精算之結果相吻合，證實了Mg2+確實是進入Ti-site，而非相同價數之Ba-site。在介電性質方面，Mg2+添加會使鐵電性降低，得到較低的介電常數，居里溫度會隨著Mg2+添加而下降，使居里溫度往低溫平移，並且造成介電常數峰的寬化。在絕緣電阻方面，Mg2+添加沒有使絕緣電阻能有效提升，推測是因為添加劑成分分布不均勻，導致晶粒大小分布不均使晶界分率降低，所以整體絕緣電阻沒有預期的提升。

In this study, using solid-state reaction method to synthesize Mg-doped barium titanate Ba(Ti1-xMgx)O3-x dielectric material. Understand the influence of Mg2+ into the Ti-site of BaTiO3 on the crystal structure, lattice parameters, Raman spectrum, specific surface area, microstructure and dielectric properties, and then discuss the feasibility of the application of this material in MLCCs.
The experimental results show that Ba(Ti1-xMgx)O3-x (x = 0, 0.01, 0.03) powder can be synthesized high purity Mg-doped BaTiO3 powder through two-stage calcination. And then through Rietveld refinement. It is known that when Mg2+ into BaTiO3, the a-axis will be extended and the c-axis will be shortened, and an increase in the volume of the crystal lattice. The result of Ti-site is consistent; in Raman spectroscopy analysis, the characteristic peak intensity of all tetragonal phase also decreases and broadens. This phenomenon indicates that BaTiO3 gradually transforms from tetragonal to cubic phase. This result is consistent with the result of Rietveld refinement. The coincidence confirms that Mg2+ is indeed into Ti-site, not Ba-site. In terms of dielectric properties, the concentration of Mg2+ will reduce the ferroelectricity, resulting in a lower dielectric constant. The Curie temperature will decrease with the concentration of Mg2+, and causing the dielectric constant peak Broaden. In terms of insulation resistance, the Mg-doped did not effectively improve the insulation resistance. It is presumed that the uneven distribution of the additive composition results in uneven grain size distribution and the reduction of the grain boundary fraction, so the overall insulation resistance did not improve as expected.

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