采用固相反应法制备了xSrTiO3-（1-x）LaAlO3（x=0．4～0．7）介电陶瓷，分析了不同x值陶瓷的结构和介电性能。结果表明：该陶瓷主相为钙钛矿固溶体，x=0．4～0．5时，为正交钙钛矿结构，在x=0．55-0．7时，为赝立方钙钛矿结构；赝立方结构的陶瓷具有较高的介电常数（ε〉50）和低介电损耗（10^-3～10^-4）及近零的温度系数；陶瓷从赝立方结构转变成正交结构时，介电常数明显下降（ε=34-45），介电损耗迅速增大（约101）；x=0．6，0．7的陶瓷具有优良的介电性能，ε〉55，tanδ在10^-3～10^-4之间（f=1MHz）；x=0．4时陶瓷具有优异的微波介电性能，ε=30．5，Qf=40177GHz，rf=-22．9×10^-6℃-1。。
xSrTiO3-（1-x）LaAlO3（x=0.4-0.7 dielectric ceramics were prepared by solid state reaction method, the structure and properties of ceramics with different x value were discussed. The results show that perovskite solid solution was the main phase of this ceramics. The perovskite were orthogonal structure and constrain cubic structure when x were 0. 4--0. 5 and 0. 55--0. 7 respectively. The ceramics with the pseudocubic structure exhibited the higher dielectric constant （ε〉 50）, lower dielectric loss （10 3_ 10-4）and near-zero temperature coefficient. The dielectric constant decreased obviously （ε= 35--45） and dielectric loss increased rapidly （about 10.2） when the ceramics transformed from orthogonai structure to the constrain cubic structure. Good dielectric properties （ε）55, tan 3 of the ceramics was about 10 -3- 10-4 at 1 MHz）were achieved when x was 0.6 and 0. 7. Excellent microwave dielectric properties of ceramic （x=0. 4） were achieved as following： ε=30.5,Qf=40177GHz,rf=-22.9×10^-6℃-1.
参考文献
| [1] | R. Freer;F. Azough .Microstructural engineering of microwave dielectric ceramics[J].Journal of the European Ceramic Society,2008(7):1433-1441. |
| [2] | Reaney IM;Iddles D .Microwave dielectric ceramics for resonators and filters in mobile phone networks[J].Journal of the American Ceramic Society,2006(7):2063-2072. |
| [3] | Sun PH.;Shan YJ.;Inaguma Y.;Itoh M.;Kitamura T.;Nakamura T. .Dielectric behavior of (1-x)LaAlO3-xSrTiO(3) solid solution system at microwave frequencies[J].Japanese Journal of Applied Physics,1998(10):5625-5629. |
| [4] | Schwingenschlogl, U;Schuster, C .Exponential decay of relaxation effects at LaAlO3/SrTiO3 heterointerfaces[J].Chemical Physics Letters,2009(4/6):354-357. |
| [5] | Seo-Yollg Cho;Kug Sun Hong;Kyung-Hyun Ko .MIXTURE-LIKE BEHAVIOR IN THE MICROWAVE DlELECTRIC PROPERTIES OF THE (l-x)LaAlO_3-xSrTiO_3 SYSTEM[J].Materials Research Bulletin: An International Journal Reporting Research on Crystal Growth and Materials Preparation and Characterization,1999(4):511-516. |
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