High Frequency Heat-stable ANNT Ceramic Material

The high frequency system with ultra-high permittivity was studied in this paper.Based on dielectric physics, material physical chemistry, crystal chemistry andcoordination chemistry, surface and interface chemistry, the modern analysis methodXRD,TEM,EDX,SEM,DTA-TG,IR spectrum method were used in the this paper.And synthetic principle is studied in the paper.As compared with the solid syntheticmethod, wet-chemical synthetic method was applied to synthesize ANNT systemstoichiometrically in order to improve the dielectric properties of the system.1. ANNT system swinging in with Na+were analyzed in detail, comparing ANTsystem. At same time, the advantage of ANNT system is studied. And the effectsof different Na+ content in ANNT system were investigated..2. The effects of dopants Bi2O3,Sb2O5,MnO2 on the properties of the ANNT systemwere investigated. It suggested that proper doping could improve the sinteringproperties and dielectric properties of the system.3. The ANNT system was synthesized by liquid state method. Contrastively, theinfluence of synthesis methods, citrate method and oxalate method, wereinvestigated. The outcome was that oxalate method lead to agglomeration muchmore than citrate method did. The particle prepared by citrate method distributeduniformly and the average particle diameter, which was about 40nm, was smaller.The average grain diameter of ceramic produced by citrate method was 0.5μm,so the dielectric properties were improved.4. The dielectric data of the system prepared by solid state method are as follows:Dielectric constant ε >400(1MHz)Temperature coefficient of capacitanceαc <0±30ppm/℃Loss tangent δ <10×10-4(1MHz)Insulation resistivity ρv >1012Ω·cmSintering temperature Ts 1050℃～1160℃5. The dielectric data of the system prepared by solid state method:Dielectrics constant ε >500(1MHz)Temperature coefficient of capacitanceαc <0±30ppm/℃Loss tangent δ <10×10-4(1MHz)Insulation resistivity ρv >1012Ω·cmSintering temperature Ts 1050℃～1160℃...