近年來，行動通訊系統的快速發展使得介電陶瓷被運用在微波頻段之共振器上越來越受到關注。藉由IC設計與調頻的方式可將微波元件尺寸微小化進而達到微波通訊產品的小型化。而較穩定與可靠的介電材料則可以有效的使元件達到小體積與高品質的要求。
　　本論文研究目的在於研發高頻性質足以用於微波頻段之陶瓷材料組成，並探討在置換不同之陽離子於系統時，其對於晶體結構所造成的改變進而造成介電特性的變化。
　　本論文分為二部分，第一部份為置換不同之陽離子於系統時對晶體結構之變化的探討，第二部份為晶體結構的改變進而對介電特性的影響。
　　第一部份主要為研究xLnAlO3-(1-x)CaTiO3系(Ln=Sm、Nd)與Zn(Ta,Nb)2O6 系之晶體結構變化。首先，隨著置換不同的陽離子，於xSmAlO3 –(1-x)CaTiO3系中，晶體呈現單一orthorhombic相之固溶體，而在xNdAlO3 –(1-x)CaTiO3系中，將藉由氧八面體的傾斜與扭曲的方式由orthorhombic對稱轉變成rhombohedra對稱，最後，在Zn(Ta,Nb)2O6 系中，Z字形鏈狀排列之八面體結構經由陽離子的互相置換而產生不同的超晶格結構。
　　第二部分則探討第一部份各個系統之晶體結構的轉變對於各系統之介電特性的影響。發現在介電材料裡，其氧八面體的對稱性主導著表現出來的介電特質，八面體對稱性越佳的介電材料，其中心離子偏移的距離越短導致較小的介電常數，而如此的結構使得材料受不和諧震盪（anharmonic motion）的影響較小，而有較高的品質因素，另一方面，不和諧震盪的效應下降會導致隨溫度的提高受晶格膨脹效應較大，所以有負值之共振頻率溫度係數。

　　Nowadays dielectric ceramics for application in resonators at microwave frequencies have been paid increasing attention due to the rapid growth on mobile communication systems. The miniaturization of the microwave telecommunication products can be achieved by miniaturizing the microwave devices using IC design and modulation. The small volume and good quality of devices can be improved by efficiently employing the more stable and reliable dielectric materials.
　　This research is to focus to exploit the composition of ceramic material with the excellent microwave dielectric properties and investigate the effect of doping different cations on the crystal structure and microwave dielectric properties.
　　Two parts were included in this work. First, how the doping of different cations induces the variation of crystal structure. Second, how the variation of crystal structure effects the dielectric properties.
　　In the first part， the variation of crystal structure of xLnAlO3-(1-x)CaTiO3 system (Ln=Sm、Nd) and Zn(Ta,Nb)2O6 system was studied. First of all，in the xSmAlO3 –(1-x)CaTiO3 system, it was observed that the single phase solid solution with orthorhombic structure was formed among whole x. On the other hand，in xNdAlO3 –(1-x)CaTiO3 system, their crystal structures transform from orthorhombic setting to rhombohedral setting by tilting and distorting of oxygen octahedron. Finally，in Zn(Ta,Nb)2O6 system，a different superstructure was obtained by altering the different cations in octahedron of zigzag train arrangement.
　　In the second part，the influence of the transformation of crystal structure on dielectric properties in each system was conducted. It was found that in the field of dielectric materials，the symmetry of oxygen octahedron plays a major role on dielectric properties. The material with more symmetric oxygen octahedron where the displacement of the centric ions is much shorter results in smaller dielectric constant. And such structure would have the better quality factor due to the less influence of the anharmonic motion. Furthermore，the dielectric ceramic could possess minus temperature coefficient of resonant frequency due to the lattice expansion effect is greater to the anharmonic motion effect as increasing temperature.

1 吳朗：電子陶瓷【介電陶瓷】；全欣資訊出版, 83年, pp267

2 R.D.Richtmyer ,“Dielectric Resonator”,J. Appl. Phys. V.10 , p191~398（1939）

3 S.B.Chan, “Microwave Bandpass Filters Contain High Q Dielectric Resonator” , IEEE Trans. on MTT , pp218~227（1968）

4 R.C.Kell , “High-permittivity Temperature-stable Ceramic Dielectric with Low Microwave Loss” ,J. Am. Ceram. Soc.,V56,pp352~354（1973）

5 T. Yamaguchi , “Newly developed Ternary（Ca,Sr,Ba）Zirconate Ceramic System for Microwave Resonator” , Ferroelectrics , V27 , pp273~276（1980）

6 E. Tillmanns , W. Hofmeister and W. H. Baur. ”Crystal Structure of the Microwave Dielectric Resonator Ba2Ti9O20”,J. Am. Ceram. Soc. , 66 , pp268~271 ,（1983）

7 D.E. Roy , “Phase Equilibria in the System BaO-TiO2” , J. Am. Ceram. Soc.,V38 , pp102~113（1955）

8 H.M. O’Bryan , “A New BaO-TiO2 Compound with Temperature Stable High Permittivity and Low Microwave Loss” , J. Am. Ceram. Soc.,V57 , pp450~453（1974）

9 K.W.Kirby , “Phase Relations in the Barium Titanate-Titanium Oxide System”,J. Am. Ceram. Soc.,V74,pp1841~1847（1991）

10 S.Hirano, T.Hayashi and A. Hattori.”Chemical Processing and Microwave Characteristics of （Zr,Sn）TiO4 Microwave Dielectrics”,J. Am. Ceram. Soc., 74 , pp1320~1324

11 王惠傑、張鳴助，”微波陶瓷介電共振器材料”，材料與社會，第65期（民國81年5月）

12 P.C.Osbond ,”The Properties and Microwave Applications
of Zirconium Titanate Stannate Ceramics”, Brit. Ceram. Proc.,V36, pp17~178

13 S.Nishigaki , H.Kato , S.Yano and R.Kamimura. ”Microwave Dielectric Properties of （Ba,Sr）O-Sm2O3-TiO2 Ceramics”, Am. Ceram. Soc. Bull., 66 , pp1405~1410（1987）

14 K. Kageyama and M.Takata,”Dielectric Characteristics of PbO-BaO-La2O3 at Microwave Frequencies”, Jpn. J. Appl. Phys., 24 , suppl.24-2 ,pp1045~1047 , （1985）

15 T.Jaakola, A. Usimaki, R. Rautioaho and S. Leppavuori,”Matrix Phase in Ceramics with Composition Near Bao-Nd2O3-5TiO2”,J.Am. Ceram. Soc., 69 ,pp c234~c235 ,（1986）

16 V.I. Butko, A.G. Belous , E.A. Nenasheva, Yu.M. Poplavko and E.F. Ushatikin,”Microwave Dielectric Properties of Barium-Lanthanoid Tetratitanates”, Sov. Phys. Solid State, 26 ,pp1783~1785 ,（1984）

17 Yu.M. Poplavko , B.A. Rotenberg , V.N. Borisov, E.A. Nenasheva , V.I. Butko and V.M. Pashkov, ”Dielectric properties of BaLa2Ti4O12 Compounds at Low Temperature”, Sov. Phys. Solid State , 28 , pp882~883 ,（1986）

18 邱碧秀:電子陶瓷材料 徐氏基金會出版,p.81,（1997）

19 G.Burns, in:Solid State Physics p.461,（1985）

20 K.Wankino,H.Murata,H.Tamura,”Far Infrared Reflection Spectra of Ba(Zn,Ta)O3-BaZrO3 Dielectric Resonator Material”, J.Am. Cream. Soc. ,Vo1.69,pp34, (1986)

21 W.E.Courtney, ”Analysis and Evaluation of a Method of Measuring the Complex Permittivity and Permeability of Microwave Insulators , IEEE.Trans.MTT,Vo1.MTT-18,pp.476-485,（1970）

22 David M.Pozar ,“Microwave Engineering ,Addison-Wesley,（1998）

23 H.S.Cannon and F.V. Lenel ,in :Proceedings of the Plansee Seminar,
Edited by F. Benesovsky Metallwerk Plansee,Reutte,pp.106,（1953）

24 V.N.Eremenko,Y.V. Naidich and I.Aienko,in:Liquid Sintefing ,Consolation New York,（1970） ,chap4

25 K.S.Hwang,Phd Thesis,Rensselaer Ploytechnic in Troy(1984)

26 ASTM C 20-83（1983）

27 R. C. Kell，A.C. Greenhaum，and G. C. E. Olds，”High-Permittivity Temperature-Stable Ceramic Dielectrics with Low Microwave Loss”, J. Am. Ceram. Soc. 56，352（1973）.

28 傅坤福，”陶瓷濾波器電路設計與製造技術”，工業材料雜誌，176期，90年8月，107-116

29 R. D. Shannon , “Revised Effective Ionic Radii and Systematic Studies of Interatomic Distances in Halides and Chalcogenides”, Acta Cryst.（1976）, A32 , pp.751

30 X. Wang , X. Zhang , L. Cai, Z. Gui and L. Li , “Forming Mechanism and Structure of the Antiphase Boundary in High Ordered PST Crystal” , Ferroelectrics ,
（1997）,Vol. 197 , pp.71-74.

31 A. M. Glazer , ”Simple Ways of Determining Perovskite Structures” , Acta Cryst. (1975). A31 , 756.

32 A. M. Glazer , “The Classification of Tilted Octahedra in Perovskites” , Acta Cryst. (1972). B28 , 3384.

33 Waburg , M., Mueller-Buschbaum , H., Z. Anorg. Allg. Chem., 508 , 55（1984）.

34 陶瓷技術手冊,傅勝利,全華科技圖書股份有限公司, chap13 ,pp403.

35 R.J.D. Tilley , in：Defect Crystal Chemistry and its Application, Chapman and Hall（1987） pp8

36 Electronic ceramics //edited by B.C.H. Steele. London ;/Elsevier Applied Science ;（c1991.） p83.

37 Lemanov , V. V. A., Sotnikov, V., Smirnova , E. P., Weihnacht, M. and Kunze, R., Perovskite CaTiO3 as an incipient ferroelectric. Solid State Commun.,（1999）,110 , 611-614.

38 V. Hippel, A.R., Dielectric and waves. John Wiely, New York,（1954.）

39 Jancar , B., Suvorov , D. and Valant , M., Microwave dielectric properties of CaTiO3-NdAlO3 ceramics. J. Master. Sci. Lett.,（2001）,20（1），71-72.