鈦酸鋇由於優異的介電性質，在工業上被廣泛的應用於被動元件、積層陶瓷、熱敏電阻器等高容電容產品，為了使製造出的電子元件能符合商用規格需求(X8R、Z5U、Y5V等)，需在鈦酸鋇中加入添加物，進行離子置換或摻雜以修整介電性及溫度特性。本研究以鈦酸鋇為基礎，透過鈣離子與鋯離子的添加，經煅燒合成單一相之(Ba0.95Ca0.05)(Ti0.88Zr0.12)O3 (BCTZ)後，再額外添加0.04與0.06莫耳的BaCO3與BCTZ反應合成單一相之(Ba,Ca)(Ti,Zr,Ca)O3 (BCTZC)粉末，並對兩種材料進行材料分析、結構分析與性質分析，以了解使鈣離子進入Ti位置後對於晶體結構與介電性質之影響。
實驗結果顯示，煅燒條件1200℃持溫4小時可得單一相之BCTZ與BCTCZ粉末，由XRD、Raman與TEM繞射圖譜的綜合分析結果，判斷其為正方晶相之結晶結構；而BCTZC與BCTZ的XRD相鑑定圖譜中，各角度的繞射峰隨著BaCO3添加量的增加，有往低角度偏移的趨勢，顯示晶體結構中的結晶面面間距增加。透過晶格常數計算得知，BCTZC與BCTZ相較，在鈣離子進入Ti位置後單位晶格的a、c軸增長，整體晶格體積有所提升，而理論密度降低。
BCTZ與BCTZC坯體可分別在1240℃持溫6小時、1280℃持溫4小時的燒結條件下緻密，獲得相對密度97%、85% - 95%的燒結體，晶粒大小約為4、6 - 8 μm；BCTZ在1 kHz下的室溫介電常數約為2400，在較高燒結溫度時其晶粒增大而介電常數降低，添加0.04莫耳BaCO3的BCTZC燒結體室溫介電常數大致為4200，而受晶粒成長影響的幅度較小，添加0.06莫耳BaCO3的BCTZC介電常數值約為6000，在較大晶粒時有降低的趨勢，而額外添加BaCO3使鈣離子進入Ti位置後，居禮溫度隨BaCO3添加量的增加有逐漸下降的趨勢，對於室溫的介電常數也有所提升。

Due to the great performance of dielectric property, barium titanate was widely used in great number of high-K capacitor products, such as passive devices, multilayer ceramic capacitors, and thermistors. To make electric device reach the EIA’s industrial standard (X7R, Z5U, Y5V, etc), it’s necessary to add dopants into BaTiO3 proceeding ion exchanging or dopant to adjust the dielectric and temperature property. Single phase Ba0.95Ca0.05Ti0.88Zr0.12 (BCTZ) was obtained in this study by Ca2+ and Zr4+ doped into BaTiO3-based material, and (Ba,Ca)(Ti,Zr,Ca)O3 (BCTZC) was reacted of BCTZ system with excess of 0.04 and 0.06 mole of barium carbonate. In the study, we analyzed the material, structure and property analysis of both composition to realize the crystal structure and dielectric property’s affect when Ba2+ was occupied in Ti site.
As the result, single phase of BCTZ and BCTZC powder could be obtained under the calcined condition of 1200℃/4 h. The crystal structure of both was tetragonal phase which was analysed by XRD, Raman, and TEM diffraction pattern. Compared with BCTZ of XRD patterns, as the more amount of BaCO3 was added, d-spacing was raised by the observation of the lower angle of all the crystal planes. According to cell parameter calculation, a and c axis were increased after Ca2+ entered the Ti site, enlarged the volume of an unit cell and decreased the theory density.
After sintering under the condition of 1240℃/6 h and 1280℃/6 h, BCTZ and BCTZC sintered bulk’s relative density was 97%, 85% - 95%. The average grain size was about 4, 6 – 8 μm. Dielectric constant of BCTZ was about 2400 under 1 kHz condition and grain growth was observed at higher temperature with lower dielectric constant. BCTZC sintered bulk with 0.04 mole BaCO3 was nearby 4200 and rarely affect by the grain size, added with 0.06 mole BaCO3 was 6000 and decreased with lager grain. With Ca2+ occupied into Ti site after excess BaCO3 were added, curie temperature was lower when there was more BaCO3 doped and also the raise of dielectric constant at room temperature had been proved

1. W. D. Kingery, H. K. Bowen, D. R. Uhlmann, Introduction to Ceramics, 2nd edition, John Wiley & Sons, New York, Chapter 18.1 (1979).
2. G. Shirane, F. Jona, and R. Pepinsky, “Some aspects of ferroelectricity,” Proc. I.R.E., 42, 1738-1793 (1955).
3. D. Hennings and A. Schnell, “Diffuse ferroelectric phase transitions in Ba(Ti1-yZry)O3 ceramics, ” J. Am. Ceram. Soc., 65 [11] 539-544 (1982).
4. J. Ravez, C. Broustera and A. Simon, “Lead-free ferroelectric relaxor ceramics in the BaTiO3–BaZrO3–CaTiO3 system,” J. Mater. Chem., 9 [7] 1609-1613 (1999).
5. H. Kishi, N. Kohzu, Y. Iguchi, J. Sugino, M. Kato, H. Ohsato, and T. Okuda, “Study of occupational sites and dielectric properties of Ho-Mg and Ho-Mn substituted BaTiO3,” Jpn. J. Appl. Phys., 39 [9B] 5533-5537 (2000).
6. A. Kirianov, T. Hagiwara, H. Kishi, and H. Ohsato, “Effect of Ho/Mg ratio on formation of core-shell structure in BaTiO3 and on dielectric properties of BaTiO3 ceramics,” Jpn. J. Appl. Phys., 41 [11B] 6934-6937 (2002).
7. S.Wang, S. Zhang, X. Zhou, B. Li, and Z. Chen, “Investigation on dielectric properties of BaTiO3 co-doped with Ni and Nb, ” Mater. Lett. 60 [7] 909–911 (2005).
8. M. Du, Y. Li, Y. Yuan, S. Zhang, and B. Tang, “A novel approach to BaTiO3-based X8R ceramics by calcium borosilicate glass ceramic doping, ” J. Electron. Mater., 36 [10] 1389-1394 (2007).
9. B. Tang, S. Zhang, X. Zhou, and Y. Yuan, “Doping effects of Mn2+ on the dielectric properties of glass-doped BaTiO3-based X8R materials,” J. Mater. Sci: Mater Electron, 18 [5] 541–545 (2007).
10. W. H. Lee and C. Y. Su “Improvement in the temperature stability of a BaTiO3-based multilayer ceramic capacitor by constrained sintering,” J. Am. Ceram. Soc., 10 [90] 3345–3348 (2007).
11. B. Li, S. Zhang, X. Zhou, S. Wang, and Zhu Chen, “Preparation of BaTiO3-based ceramics by nanocomposite doping process,” J. Mater. Sci., 42 [6] 2090–2096 (2007).
12. B. Tang, S. Zhang, X. Zhou, D.Wang, and Y. Yuan, “Regression analysis for complex doping of X8R ceramics based on uniform design,” J. Electron. Mater, 36 [10] 1383-1388 (2007).

13. Y. Mizuno, T. Hagiwara, and H. Kishi, “Microstructural design of dielectrics for Ni-MLCC with ultra-thin active layers,” J. Ceram. Soc. Jpn., 115 [6] 360-364 (2007).
14. B. Tang, S. R. Zhang, Y. Yuan, X. H. Zhou, and Y. S. Liang, “Influence of CaZrO3 on dielectric properties and microstructures of BaTiO3-based X8R ceramics,” Sci. China Ser. E-Tech. Sci., 51 [9] 1451-1456 (2008).
15. K. R. Chowdary and E. C. Subbarao, “Liquid phase sintered BaTiO3,” Ferroelectric, 37 [1-4] 689-692 (1981).
16. D. A. Toline and J. B. Blum, “Effect of Ba : Ti ratio on densification of LiF-fluxed BaTiO3,” J. Am. Ceram. Soc., 68 [11] C292-C294 (1985).
17. B. Jaffe, W. R. Cook Jr., and H. Jaffe, Piezoelectric Ceramics, Academic, Press, London (1971).
18. 汪建民等著，陶瓷技術手冊(上)，中華民國產業科技發展協進會，413-414，台灣台北，1994。
19. Y. H. Han, J. B. Appleby, and D. M. Smyth, “Calcium as an acceptor impurity in BaTiO3,” J. Am. Ceram. Soc., 70 [2] 96-100 (1987).
20. H. M. Chan, M. P. Harmer, M. Lal, and D. M. Smyth, “Calcium site occupancy in BaTiO3,” Mater. Res. Soc. Symp. Proc., 31, 345-350 (1984).
21. J. G. Park, T.S. Oh, and Y. H. Kim, “Dielectric properties and microstructural behaviour of B-site calcium-doped barium titanate ceramics,” J. Mater. Sci., 27 [21] 5713-5719 (1992).
22. L. Zhang, O. P. Thakur, A. Feteira, G. M. Keith, A. G. Mould, D. C. Sinclair, and A. R. West, “Comment on the use of calcium as a dopant in X8R BaTiO3-based ceramics,” Appl. Phys. Lett., 90 [14] 142914 (2007).
23. S. Lee and C. A. Randall, “A modified Vegard's law for multisite occupancy of Ca in BaTiO3-CaTiO3 solid solutions,” Appl. Phys. Lett., 92 [11] 111904 (2008).
24. S. M. Neirman, “The curie point temperature of Ba(Ti1-xZrx)O3 solid solution,” J. Mater. Sci., 23 [11] 3973-3980 (1988).
25. P. S. Dobal, A. Dixit, and R. S. Katiyar, “Micro-Raman scattering and dielectric investigations of phase transition behavior in the BaTiO3-BaZrO3 system,” J. Appl. Phys., 89 [12] 8085-8091 (2001).
26. B. Tang, S. R. Zhang, Y. Yuan, X. H. Zhou, and Y. S. Liang, “Influence of CaZrO3 on dielectric properties and microstructures of BaTiO3-based X8R ceramics,” Sci. China Ser. E-Tech. Sci., 51 [9] 1451-1456 (2008).

27. Z.Q. Zhuang, M. P. Harmer, D.M. Smyth, and R. E. Newnham, “The effect of octahedrally-coordinated calcium on the ferroelectric transition of BaTiO3,” Mater. Res. Bull., 22 [10] 1329-1335 (1987).
28. X. W. Zhang, Y. H. Han, M. Lal, and D. M. Smyth, “Defect chemistry of BaTiO3 with additions of CaTiO3,” J. Am. Ceram. Soc., 70 [2] 100-103 (1987).
29. D. F. K. Hennings and H. Schreinemacher, “Ca-acceptors in dielectric ceramics sintered in reducive atmospheres,” J. Eur. Ceram. Soc., 15 [8] 795-800 (1995).
30. G. Burns, “Lattice modes in ferroelectric perovskites. II. Pb1-xBaxTiO3 including BaTiO3,” Phys. Rev. B：Solid State, 10 [5] 1951-1959 (1974).
31. J. D. Freire and R. S. Katiyar, “Lattice dynamics of crystals with tetragonal BaTiO3 Structure,” Phys. Rev. B, 37 [4] 2074-2085 (1988).
32. T. Hoshina, H. Kakemoto, Takaaki, S. Wada, and M. Yashima, “Size and temperature induced phase transition behaviors of barium titanate nanoparticles,” J. Appl. Phys., 99 [5] 054311 (2006).
33. B. D. Begg, S. Kim, Finnie, and E. R. Vance, “Raman study of the relationship between room-temperature tetragonality and the curie point of barium titanate,” J. Am. Ceram. Soc., 79 [10] 2666-2672 (1996).
34. M. C. Chang and S. C. Yu, “Raman study for (Ba1-xCax)TiO3 and Ba(Ti1-yCay)O3 crystalline ceramics,” J. Mat. Sci. Let., 19 [15] 1323-1325 (2000).
35. C. Y. Huang, Thermal expansion behavior of sodium zirconium phosphate structure type materials, Ph. D. Thesis, The Pennsylvania State University, U.S.A. (1990).
36. B. D. Cullity, Elements of X-Ray Diffraction, 2nd edition., Addison-Wesley Pub. Co., Inc., Reading, MA, 350-368 (1978).