臺灣博碩士論文加值系統

在本研究中，將分別使用傳統固態反應法在K0.5Na0.5NbO3(簡稱KNN)系鐵電陶瓷中摻雜不同量的Li2CO3形成(1-x)K0.5Na0.5NbO3+xLi2CO3鐵電陶瓷，並且使用Ta2O5取代Nb2O5來形成K0.5Na0.5(Nb1-xTax)O3鐵電陶瓷，並藉由XRD、SEM、介電常數、相對密度等的分析，來得到最佳組成與製程參數。由實驗結果可以很明顯的看出，摻雜Li2CO3可提高居禮溫度(Tc)約20~50 oC至465 oC，其中，由形變相界區(MPB)之分析可知此時KNN之晶相會由正方晶(T, tetragonal)結構轉變成立方晶(C, cubic)結構，且其介電常數也會隨著溫度之增加而明顯地增加；另一方面，在KNN系鐵電陶瓷中，使用Ta2O5來取代部分的Nb2O5將會使其燒結溫度由1100 ℃增加至1120 ℃，其平均晶粒大小為3　μm且其相對密度可高達理論密度(4.51　g/cm3)的95.6 %。最後，Li摻雜KNN系鐵電陶瓷以及Ta取代KNN系鐵電陶瓷之介電、鐵電和燒結特性將在本論文中有詳盡的探討。

In this study, different contents of Li2CO3 and Ta2O5 were doped and substituted into the lead-free K0.5Na0.5NbO3-based (KNN-based) ferroelectric ceramics to form K0.5Na0.5(Nb1-XTaX)O3 and (1-x)K0.5Na0.5NbO3+xLi2CO3 ceramics by the conventional solid-state method, respectively. By the analysis of XRD, SEM, dielectric constant, and relative density, the optimum composition and fabricated parameters will be obtained. From the experimental results, it is evident seen that, the doping of Li2CO3 could increase the Curie temperature (Tc) about 20~50 ℃ to 465 ℃. In addition, from the analysis of the Morphotropic Phase Boundary (MPB), the crystal phase of this KNN-based ceramics were changed from the tetragonal to the cubic structures and its dielectric constants increased obviously as the temperature increased. On the other way, in the KNN-based ceramics, the substitution of Ta2O5 for Nb2O5 would increase the sintering temperature from 1100 ℃ to 1120 ℃, the average grain size was 3 μm, and the relative density of K0.5Na0.5(Nb0.95Ta0.05)O3 ceramics could achieve about 95.6 % of the theorical density (4.51 g/cm3). Finally, in this thesis, all of the dielectric, ferroelectric and sintering characteristics of the Ta-substituted and Li-doped KNN-based ferroelectric ceramics would be investigated in detail.

摘要 i
英文摘要 ii
誌謝 iii
目次 iv
表目錄 vi
圖目錄 vii
第一章 緒論 1
1.1 前言 1
1.2 研究方向及目的 3
第二章 理論介紹 4
2.1 晶體結構及電性質 4
2.1.1 KNbO3 (鈮酸鉀) 4
2.1.2 NaNbO3 (鈮酸鈉) 4
2.1.3 (K1-xNax)NbO3(鈮酸鉀納) 8
2.1.4 鈮酸鉀納固溶系統 11
2.2 介電材料性質 12
2.2.1 極化機制 12
2.2.2 介電特性參數 15
2.3 鐵電材料性質 18
2.3.1 鐵電效應 18
2.3.2 鐵電滯迴曲線 18
2.4再結晶與粒成長(Grain growth) 19
2.5形變相界(morphotropic phase boundary, MPB) 20
第三章 實驗方法與步驟 21
3.1 樣品之製備 21
3.1.1 研究之材料成分 21
3.1.2 起始原料 21
3.2 粉末及燒結體製備 22
3.2.1 粉末製備 22
3.2.2 燒結體製備 22
3.3 材料特性分析 23
3.3.1 X-Ray 繞射分析 24
3.3.2 表面微結構分析 (SEM) 25
3.3.3 密度量測 (Archimedes’s Method) 26
3.4 材料性質量測 27
3.4.1 介電性質量測之樣品準備 27
3.4.2 介電性質量測 27
第四章 結果與討論 28
4.1 K0.5 Na0.5NbO3–based之特性探討 28
4.1.1 X-Ray繞射分析 28
4.1.2 SEM晶體表面結構分析 29
4.1.3 密度分析 29
4.1.4 介電特性分析 31
4.2 (1-x) K0.5 Na0.5NbO3 + xLi2CO3 系列之特性探討 33
4.2.1 X-Ray繞射分析 33
4.2.2 SEM晶體表面結構分析 35
4.2.3 密度分析 37
4.2.4 介電特性分析 39
4.3 K0.5Na0.5(Nb1-xTax)O3 系列之特性探討 44
4.3.1 X-Ray繞射分析 44
4.3.2 SEM晶體表面結構分析 46
4.3.3 密度分析 51
4.3.4 介電特性分析 52
第五章 結論 59
參考文獻 60

[1]Y. J. Dai, X. W. Zhang,and K. P. Chen, “Morphotropic phase boundary and electrical properties of K1-xNaxNbO3 lead-free ceramics,” App. Phy. Lett., Vol.94, 042905, 2009.
[2]J. F. Scott, C. A. P. de Araujo, L. D. McMillan, H. Yoshimori, H. Watanable, T. Mihara, M. Azuma, T. Ueda, T. Ueda, D. Ueda, and G. Kano, “Ferroelectric Thin Films in Integrated Microelectronic Devices,” Ferroelectrics, Vol. 133, pp. 47-60, 1992.
[3]G. H. Haerting, “Ferroelectric thin films for electronic applications,” J. Vac. Sci. Tec., Vol. 9, No. 3, pp. 414-420, 1991.
[4]L. M. Sheppard, “Advances in Processing of Ferroelectric Thin Film,” Ceramic Bulletin, Vol. 71, pp. 85-89, 1992.
[5]M. Sayer and K. Sreenivas, “Ceramic Thin Film: Fabrication and Applications,” Science, Vol. 247, pp. 1056-1060, 1990.
[6]B. Jaffe, W. R. Cook, and H. Jaffe, Piezoelectric ceramics, academic, New York, 1971.
[7]H. Ishii, H. Nagate, and T. Takenaka, “Morphotropic phase boundry and electrical properties of bisumuth sodium titanate-potassium niobate solid-solution ceramics,” Jpn. J. Appl. Phys., Vol. 40, No. 9[B], pp. 5660-5663, 2001.
[8]H. Odagawa and K. Yamanouchi, “Superhigh electromechanical coupling and zero-temperature characteristics of KNbO3 and wide band filter applications,” Jpn. J. Appl. Phys., Vol. 37, pp. 2929-2932, 1998.
[9]H. D. Megaw, “The seven phases of sodium niobate,” Ferroelectrics, Vol.7, pp. 87-92, 1974.
[10]R. Wang, R. Xie, T. Sekiya, and Y. Shimojo, “Fabrication and characterization of potassium-sodium niobate piezoelectric ceramics by spark-plasma-sintering method,” Mat. Res. Bul., Vol.39, pp. 1709-1713, 2004.
[11]吳朗，電子陶瓷 (介電)，全欣科技圖書，1994。
[12]S. Narayana Murty, K. V Ramana Murty, K. Umakantham, and A. Bhanumathi, “Modified (NaK)NbO3 ceramics for transducer applications,” Ferroelectrics, Vol. 102 , pp. 243-247, 1990.
[13]L. Egerton and D.M. Dillon, “Piezoelectric and dielectric properties of ceramics in the system potassium-sodium niobate,” J. Am. Ceram. Soc., Vol.42 , pp. 438-442, 1959.
[14]B. Jaffe, R. S. Roth, and S. Marzullo, “Properties of piezoelectric ceramics in the solid-solution series lead titanate zirconate-lead oxide: tin oxide and lead titanate - lead hafnate,” J. Res. Natl. Bur. Stand., Vol.55, pp. 239-254, 1955.
[15]R. H. Dungan and R. D. Golding, “Polarization of NaNbO3-KNbO3 ceramic solid solutions,” J. Am. Ceram. Soc., Vol. 48, pp. 601-607, 1965.
[16]R. E. Jaeger and L. Egerton, “Hot pressing of potassium-sodium niobates,” J. Am. Ceram. Soc., Vol.45, pp. 209-213, 1962.
[17]G. H. Haertling, “Properties of hot-pressed ferroelectric alkali niobate ceramics,” J. Am. Ceram. Soc., Vol.50, pp. 329-330, 1967.
[18]K. Singh, V. Lingwal, S. C. Bhatt, N. S. Panwar, and B. S. Semwal, “Dielectric properties of potassium sodium niobate mixed system,” Mat. Res. Bull., Vol. 36, pp. 2365-2374, 2001.
[19]M. A. L. Nobre and S. Lanfredi, “Dielectric loss and phase transition of sodium potassium niobate ceramic investigated by impedance spectroscopy,” Catal. Today, Vol. 78, pp. 529-538, 2003.
[20]V. J. Tennery, “High-temperature phase transitions in NaNbO3,” J. Am. Ceram. Soc., Vol. 48, pp. 537-539, 1965.
[21]F. Jona and G. Shirane, Ferroelectric crystals, Peramon, New York, 1962.
[22]M. Kosec and D. Kolar, “On activated sintering and electrical properties of NaKNbO3,” Mater. Res. Bull., Vol. 50, pp. 335-340, 1975.
[23]A. Wood, “Polymorphism in potassium niobate, sodium niobate, and other ABO3 compounds,” Acta Crystallogr., Vol. 4, pp. 353-362, 1951.
[24]L. Egerton and C. A. Bieling, “Isostatically hot-pressed sodium-potassium niobate transducer material for ultrasonic devices,” Ceram. Bull., Vol. 47, pp. 1151-1156, 1968.
[25]M. Ichiki, L. Zhang, M. Tanaka, and R. Maeda, “Electrical properties of piezoelectric sodium-potassium niobate,” J. Eur. Ceram. Soc., Vol. 24, pp. 1693-1697, 2004.
[26]Y. Guo, K. Kakimoto, and H. Ohsato, “Ferroelectric-relaxor behavior of (Na0.5K0.5)NbO3-based ceramics,” J. Phys. Chem. Sol., Vol. 65, pp. 1831-1835, 2004.
[27]S. Y. Chu, W.Water, Y.D. Juang, and J.T. Liaw, “Properties of (Na,K)NbO3 and (Li,Na,K)NbO3 ceramic mixed systems,” Ferroelectrics, Vol. 287, pp. 23-33, 2003.
[28]Y. Guo, K. Kakimoto, and H. Ohsato, “(Na0.5K0.5)NbO3-LiTaO3 lead-free piezoelectric ceramics,” Jpn. Mater. Lett., Vol. 59, pp. 241-244, 2005.
[29]Y. Guo, K. Kakimoto, and H. Ohsato, “Dielectric and piezoelectric properties of lead-free (Na0.5K0.5)NbO3-SrTiO3 ceramics,” Solid State Commun., Vol. 129, pp. 279-284, 2004.
[30]Y. Guo, K. Kakimoto, and H. Ohsato, “Structure and electrical properties of lead-free (Na0.5K0.5)NbO3-BaTiO3 ceramics,” Jpn. J. Appl. Phys., Vol. 43, pp. 6662-6666, 2004.
[31]R. Wang, R. Xie, T. Sekiya, Y. Shimojo, Y. Akimune, N. Hirosaki, and M. Iton, “Piezoelectric properties of spark-plasma-sintered (Na0.5K0.5)NbO3-PbTiO3 ceramics,” Jpn. J. Appl. Phys., Vol. 41, pp. 7119-7122, 2002.
[32]Y. Guo, K. Kakimoto, and H. Ohsato, “Ferroelectric-relaxor behavior of (Na0.5K0.5)NbO3-based ceramics,” J. Phys. chem. sol., Vol. 65, pp. 1831-1835, 2004.
[33]謝煜弘，電子材料，新文京開發出版有限公司，2003。
[34]廖繼滄，鈮酸鋰、鈮酸鈉、鈮酸鉀陶瓷系列之研製及其特性探討。國立成功大學電機工程研究所碩士論文，2002。
[35]劉文貴，(Na0.5K0.5)NbO3 - SrZrO3 系統之合成、分析、及介電性質。國立成功大學資源工程研究所碩士論文，2005。
[36]E. Cross, “Lead-free at last,” Nature, Vol. 432, pp. 24-25, 2004.
[37]Y. Saito, H. Takao, T. Tani, T. Nonoyama, K. Takatori, T. Homma, T. Nagaya, and M. Nakamura, “Lead-free piezoelectric,” Nature, Vol. 432, pp. 84-87, 2004.
[38]W. D. Kingery, H. K. Bowen, and D. R. Uhlmann, Introduction to ceramics, 2nd Ed., John Wiley and Sons, New York, 1976.
[39]K. Matsumoto, T. Hiuga, K. Takada, and H. Ichimura, “Ba (Mg1/3Ta2/3O3) Ceramics with Ultra-Low Loss at Microwave Frequencies,” presented at IEEE (Institute of Electrical and Electronic Engineers, New York, 1986), pp. 118-121, 1986.
[40]黃忠良，精密陶瓷材料概論，復漢出版社，1992。
[41]陳皇均，陶瓷材料概論，曉園出版社，台北市，3版，1992。
[42]S. Yangyun, R. J. Brook, “Preparation of Zirconia-Toughened Ceramics by Reaction Sintering,” Sci. Sintering, Vol. 17[1], pp. 35-47, 1985.