Preparation Of SrTiO₃ Ceramics And Study On Their Dielectric Properties

SrTiO₃ ceramics is widely used in energy storage devices,electronic,sensor,dynamic random access memory and multilayer ceramic capacitors,due to its high dielectric constant and low dielectric loss.However,the application of new energy storage has promoted the processing of high-frequency device materials,low dielectric loss,high dielectric constant,the dielectric constant of significant field dependence and high energy storage density.With the rapid development of modern industry,the electronic storage devices are increasingly high requirements,and there are still some problems remain to be solved in industrial production.Based on the above,we use SrTiO₃ as the research object,hoping for preparing SrTiO₃ with high dielectric ceramics,low dielectric loss and excellent breakdown strength by some improvement and doping method.This paper is according to a certain proportion in the preparation of ultrafine particle size SrTiO₃ solid solution ceramics by traditional solid phase method,then the thickness on the ceramic substrate 0.2mm is prepared with the method of casting.The influences of interface which is the electrode and SrTiO₃ ceramic is discussed on the electrical properties.The sample is tested by X ray diffraction the analysis?XRD?,scanning electron microscopy?SEM?,magnetic testing system of ferroelectric ceramic crystal structure and micro morphology.Results show that the surface burning silver electrode and sputtering silver electrode have a great influence on the test application of the ceramic plates.At the 880 temperature,the dielectric constant of silver electrode sputtering is coated with silver electrode approximation 2 times,rosing from 12000 to 23000,temperature coefficient is less than 20%;with the same conditions,improving the sintering temperature and prolonging the time of burning silver electrode are good for density curing of electrode.By simulation and single crystal samples treatment,when the contact resistance is smaller between the electrode and the surface of the sample,the dielectric constant is greater;when two contact is the ohmic,dielectric constant reachs the best.SrTiO₃ single which is doped Nb can be effectively stripped from the electrode contact resistance,grain boundary resistance and grain resistance from low to high frequency.The resistance is decreased,capacitor correspondences.Zview simulation also obtained the corresponding results.This makes the internal structure of each boundary layer capacitor clear,providing more effective role in guiding for production of the material.In order to further explore the grain size uniformity on the dielectric properties of SrTiO₃ ceramic,we change the temperature in semi conductive links to study the grain,improving the dielectric properties.we obtained the particle size with the sintering temperature increasing and then decreasing through experiments.The dielectric constant and the voltage value were increasing firstly and then decreasing with the increase of temperature,the performance of ceramic substrate of the best sintering was in 1440 temperature and 2 hours with ensuring gas ratio,the particle size was nearly 2 ?m,not only the ceramic substrate can get a much more compact structure,the number of pores the material was reduced,thereby reducing the loss,improving the dielectric properties.The dielectric constant can reach 24000,the loss around 0.03,the temperature coefficient is less than 20%,the breakdown strength is 1.5kV/mm to meet the requirements of electronic devices.With the further development of science and technology,making the ceramic with the broader market,the important industrial and military enterprises are higher on the ceramic substrate voltage than before,researching on ceramic substrate oxidation agent has become the focus.In the end,changing oxidant formula of different improves the dielectric properties.Under the oxidation temperature of 1060 temperature,Pb3O4,Bi2O₃,CuO,B of oxidant glass four different proportion were carried out.The addition of pure B glass has higher dielectric properties than other types of oxidation agent ratio,the dielectric constant 25000,the dielectric loss 0.01 at high frequency,the breakdown strength of 1.5kV/mm,what is more,it does not contain Pb,Bi and other heavy metal ions,environmental protection.