本研究添加Co於Cu-Zn-ferrite中，並研究其對顯微結構與電性之影響，使用之化學組成為(CuO)0.2(ZnO)0.8(Co3O4)x/3(Fe2O3)0.986-2x；x=0, 0.02, 0.04, 0.08, 0.1及(CuO)0.2(ZnO)0.8-x(Co3O4)x/3(Fe2O3)0.986；x=0.02, 0.04, 0.08, 0.1。樣品以傳統固態反應法製備，在研究中發現，添加Co會使得兩種配方中的Cu2+, Cu+, Fe2+與 Fe3+離子在晶界與晶粒間數量與分布產生不同，其中第一種配方在Co添加量增加時會使得Cu離子於晶界處富集，此外，於添加量高於X=0.04後會產生CuO與ZnO之二次相，而第二種配方隨著Co添加量的增加，其Cu2+, Cu+, Fe2+, 與 Fe3+於晶界與晶粒處的產生另一種分布。上述現象使樣品晶粒與晶界的導電活化能產生變化，影響其空間極化現象，進而使得樣品之介電性質改變。

The effects of the addition of Co3O4 addition on microstructure and electrical properties of Cu-Zn-ferrites were investigated. The CuZn ferrites with the compositions of (CuO)0.2(ZnO)0.8(Co3O4)x/3 (Fe2O3) 0.986-2x; x = 0 , 0.02, 0.04, 0.08, 0.1, and (CuO)0.2(ZnO)0.8-x(Co3O4)x/3 (Fe2O3) 0.986; x = 0.02, 0.04, 0.08, 0.1 were synthesized using solid state reaction. It was observed that the addition of cobalt will change the amounts and distribution of the Cu2+, Cu+, Fe2+, and Fe3+ in the grain and grain boundary. For the first composition, the segregation of copper ions at the grain boundary was observed as the substitution of cobalt was increased. Moreover, as the x value was increased above 0.04, the second phases of CuO and ZnO were found. For the second composition, the amount of copper ions near the grain boundary decreased with increasing x value. The different amounts and distribution of the Cu2+, Cu+, Fe2+, and Fe3+ in the grain and grain boundary for the samples added with different amounts of cobalt changed the conductivity activation energies of the grain and grain boundary, and hence affected the space polarization and the dielectric properties.

1. K. Tsuzuki, “Multilayer coil.” in., PCT/JP2005/009975, 2007.
2. K. Tsuzuki, “Multilayer coil.” in., PCT/JP2006/318266, 2007.
3. J.-C. Jao, P. Li, and S.-F. Wang, “Characterization of Inductor with Ni–Zn–Cu Ferrite Embedded in B2O3–SiO2Glass,” Japanese Journal of Applied Physics, 46[9A] 5792-5796 (2007).
4. A. Rafferty, Y. Gun’ko, and R. Raghavendra, “An investigation of co-fired varistor-NiZn ferrite multilayers,” Materials Research Bulletin, 44[4] 747-752 (2009).
5. B. Vaidhyanathan, K. Annapoorani, J. Binner, and R. Raghavendra, “Microwave Sintering of Multilayer Integrated Passive Devices,” J Am Ceram Soc, 93[8] 2274-2280 (2010).
6. A. Nakano and S. Saito, “Composite Multilayer Parts.” in, Vol. US Patent：5,476,728. 1995.
7. M. Penchal Reddy, G. Balakrishnaiah, W. Madhuri, M. Venkata Ramana, N. Ramamanohar Reddy, K. V. Siva Kumar, V. R. K. Murthy, and R. Ramakrishna Reddy, “Structural, magnetic and electrical properties of NiCuZn ferrites prepared by microwave sintering method suitable for MLCI applications,” Journal of Physics and Chemistry of Solids, 71[9] 1373-1380 (2010).
8. TDK, “High-Precision Multilayering Technology Combines Small Size and High-Q Rating,” Tech Journal (2011).
9. M. D. Kingery and e. a. D.R. Uhlmann, “Introduction to ceramics.” John Wiley & Sons: New York, (1976).
10. 呂秉軍, “離子擴散對鎳銅鋅鐵氧磁體與硼系玻璃陶瓷共燒的影響,” 成功大學,碩士論文 (2012).
11. C. G. Koops, “On the Dispersion of Resistivity and Dielectric Constant of Some Semiconductor at Audiofrequencies.,” Phys. Rev, 83[1] 121-124 (1951).
12. K. B. Uhlmann and 陳皇鈞譯, “陶瓷材料概論.” 曉園出版社, (1988).
13. L. G. Vanuitert, “Dielectric Properties of and Conductivity in Ferrites,” P Ire, 44[10] 1294-1303 (1956).
14. 邱碧秀, “電子陶瓷材料,” pp. 129-153. in. 徐氏基金會, 台北市, 1988.
15. D.C. Sinclair and A.R. West, “Impedance and modulus spectroscopy of semiconducting BaTiO3 showing positive temperature of resistance.,” J. Appl. Phys., 66[8] 3850-3856 (1989).
16. 劉益郎, “添加CuO與TiO2對鋅鐵氧磁體結構與電磁性質之研究,” 國立成功大學碩士論文 (2007).
17. W. Schiessl, W. Potzel, H. Karzel, M. Steiner, G. M. Kalvius, A. Martin, M. K. Krause, I. I. Halevy, J. Gal, W. Schafer, G. Will, M. Hillberg, and R. Wappling, “Magnetic properties of the ZnFe2O4 spinel,” Physical review. B, Condensed matter, 53[14] 9143-9152 (1996).
18. A. Pavese, D. Levy, and A. Hoser, “Cation distribution in synthetic zinc ferrite (Zn0.97Fe2.02O4) from in situ high-temperature neutron powder diffraction,” Am Mineral, 85[10] 1497-1502 (2000).
19. 金重勳, “磁性技術手冊.” 中華民國磁性技術協會, (2002).
20. B. D. Cullity, “Elements Of X Ray Diffraction,” pp. 104-137. Addison-Wesley Publishing Company, Inc., (1956).
21. 山口喬, 柳田博明, 岡本祥一, and 近桂一郎(黃忠良譯著), “磁性陶瓷.” 復漢出版社: 台南市, (2001).
22. J. A. Gomes, M. H. Sousa, F. A. Tourinho, J. Mestnik, R. Itri, and J. Depeyrot, “Rietveld structure refinement of the cation distribution in ferrite fine particles studied by X-ray powder diffraction,” Journal of Magnetism and Magnetic Materials, 289 184-187 (2005).
23. S.M. Antao and e. a. I. Hassan, “Cation ordering in magnesioferrite, MgFe2O4, to 982 °Cusing in situ synchrotron X-ray powder diffraction.,” Am Mineral, 90 219-228 (2005).
24. A. Pitnis, “Introduction to mineral sciences..” Cambridge University Press, (1992).
25. A. R. West, “Basic Solid State Chemistry..” John Wiley & Sons: Chichester, (1999).
26. A. R. West, “Solid state chemistry and its applications,” pp. vii, 734 p. Wiley: Chichester West Sussex ; New York, (1984).
27. E. J. W. Verwey and E. L. Heilmann, “Physical Properties and Cation Arrangement of Oxides with Spinel Structures.,” J. Chem. Phys., 4[15] 174-187 (1946).
28. L. E. B. J.G. Sole and e. al., “An introduction to the Optical Spectroscopy of Inorganic Solids..” JohnWiley & Sons: Chichester, (2005).
29. T. T. Ahmed, I. Z. Rahman, and M. A. Rahman, “Study on the properties of the copper substituted NiZn ferrites,” Journal of Materials Processing Technology, 153 797-803 (2004).
30. E. Rezlescu, N. Rezlescu, P. D. Popa, L. Rezlescu, C. Pasnicu, and M. L. Craus, “Effect of Copper Oxide Content on Intrinsic Properties of MgCuZn Ferrite,” Materials Research Bulletin, 33[6] 915-925 (1998).
31. J. J. Shrotri, S. D. Kulkarni, C. E. Deshpande, A. Mitra, S. R. Sainkar, P. S. Anil Kumar, and S. K. Date, “Effect of Cu substitution on the magnetic and electrical properties of Ni–Zn ferrite synthesised by soft chemical method,” Materials Chemistry and Physics, 59[1] 1-5 (1999).
32. E. Rezlescu, L. Sachelarie, P. D. Popa, and N. Rezlescu, “Effect of Substitution of Divalent Ions on the Electrical and Magnetic Properties of Ni–Zn–Me Ferrites,” Ieee T Magn, 36[6] (2000).
33. A. Bonincontro, C. Cametti, and A. Dibiasio, “Effect of Volume Ion Polarizations on Maxwell-Wagner Dielectric Dispersions,” J Phys D Appl Phys, 13[8] 1529-1535 (1980).
34. N. Ponpandian and A. Narayanasamy, “Influence of grain size and structural changes on the electrical properties of nanocrystalline zinc ferrite,” Journal of Applied Physics, 92[5] 2770 (2002).
35. D. Arcos, M. Vazquez, R. Valenzuela, and M. Vallet-Regi, “Grain boundary impedance of doped Mn-Zn ferrites,” J Mater Res, 14[3] 861-865 (1999).
36. N. Rezlescu, E. Rezlescu, P. D. Popa, M. L. Craus, and L. Rezlescu, “Copper ions influence on the physical properties of a magnesium-zinc ferrite,” Journal of Magnetism and Magnetic Materials, 182[1-2] 199-206 (1998).
37. Zhenxing Yue *, L. L. Ji Zhou, Xiaohui Wang, and Z. Gui, “Effect of copper on the electromagnetic properties of Mg–Zn–Cu ferrites prepared by sol–gel auto-combustion method,” Materials Science and Engineering, 86 64-69 (2001).
38. N. Atsuyuki, N. Takeshi, and S. Satoshi, “Composite Multilayer Parts.” in. Edited by T. Corporation, 1995.
39. A. L. Rosa-Toro, R. Berenguer, C. Quijada, F. Montilla, E. Morallon, and J. L. Vazquez, “Preparation and characterization of copper-doped cobalt oxide electrodes,” The journal of physical chemistry. B, 110[47] 24021-24029 (2006).
40. B. Chi, H. Lin, and J. Li, “Cations distribution of CuxCo3−xO4 and its electrocatalytic activities for oxygen evolution reaction,” International Journal of Hydrogen Energy, 33[18] 4763-4768 (2008).
41. M. Takahashi and M. E. Fine, “MAGNETIC BEHAVIOR OF QUENCHED AND AGED CoFe//2O//4-Co//3O//4 ALLOYS,” Journal of Applied Physics, 43[10] 4205-4216 (1972).
42. I. C. Nlebedim, A. J. Moses, and D. C. Jiles, “Non-stoichiometric cobalt ferrite, CoxFe3−xO4 (x=1.0 to 2.0): Structural, magnetic and magnetoelastic properties,” Journal of Magnetism and Magnetic Materials, 343[0] 49-54 (2013).
43. J. W. D. Martens, W. L. Peeters, H. M. van Noort, and M. Erman, “Optical, magneto-optical and mössbauer spectroscopy on Co3+ substituted cobalt ferrite Co2+Fe2−xCo3+xO4(0 < x < 2),” Journal of Physics and Chemistry of Solids, 46[4] 411-416 (1985).
44. E. J. W. V. a. E. L. Heilmann, “Physical Properties and Cation Arrangement of Oxides with Spinel Structures,”, J. Chem. Phys, 15[4] 174-187 (1946).
45. Y. Zhang, J. Lin, and D. J. Wen, “Structure, Infrared Radiation Properties and Mossbauer Spectroscopic Investigations of Co0.6Zn0.4NixFe2-xO4 Ceramics,” J Mater Sci Technol, 26[8] 687-692 (2010).
46. J. G. M. de Lau, R. M. van den Heuvel, and A. B. van Groenou, “Trivalent cobalt in nickel-zinc ferrites—I. chemical problems,” Journal of Physics and Chemistry of Solids, 35[9] 1073-1080 (1974).