38results about How to "High dielectric tunability" patented technology

This invention discloses an adjustable dielectric constant, low temperature sintered and composite microwave ceramic material. The components, based on the total weight percentages, are: Bal-xSrxTiO(x=0.3-0.6) being 20.0-97.5%, M2TiO4(M=Mg or Zn)being 0.0-77.5%, xB2O3.yLi2O glass (x/y=0.5-1.0) being 2.5-15.0%. This invention also discloses the method for preparing said product. The advantages are adjustable dielectric constant and being low temperature sintered.

The invention discloses a method for preparing a binary alternatively-doped BST membrane, belongs to the technical field of functional materials, and relates to a method for preparing a nanocrystalline BST membrane. The method adopts binary doping of Mn and Y, namely, carries out Mn or Y doping on an odd layer membrane and carries out Y or Mn doping on an even layer membrane; and the method adds a pre-crystallization processing step between cooling and crystallization steps. The membrane prepared by the method is smooth and compact with no crack or shrinkage cavity, and can greatly enhance the comprehensive dielectric tuning performance of the nanocrystalline BST membrane; and the obtained nanocrystalline BST membrane has a dielectric tuning rate of over 30.0 percent, a dielectric loss of less than 2.0 percent, a K factor of greater than 15.5, a high dielectric strength and a stable frequency characteristic and a temperature characteristic. The nanocrystalline BST membrane prepared by the method can be used for preparing a microwave tuning device (such as a phase shifter) instead of a ferrite and a semiconductor so as to remarkably reduce the manufacturing cost of the microwave tuning device; and furthermore, the nanocrystalline BST membrane prepared by the method is applicable for magnetic recording, pyroelectric focal plane arrays and the like.

The invention belongs to the technical field of electric materials and devices, in particular to a dielectric adjustable BST-MB two-phase compound microwave ceramic material and a method for preparing the same. The dielectric adjustable two-phase compound microwave ceramic material consists of BaxSr1-xTiO3 and Mg2B2O6. The dielectric adjustable BST-MB two-phase compound microwave ceramic material has the advantages of low sintering temperature and big change of a dielectric constant along with the change of external DC electric fields and is applicable to the two-phase compound microwave ceramic medium ferroelectric phase shifter material of a adjustable microwave device.

The invention provides a barium strontium titanate/zinc niobate bismuth heterogeneous structural material, which comprises at least a layer of barium strontium titanate layer and at least a layer of zinc niobate bismuth layer, wherein the barium strontium titanate layer is mixed with manganese. The barium strontium titanate/zinc niobate bismuth heterogeneous structural material organically combines high dielectric adjustability of barium strontium titanate materials and low dielectric loss property of zinc niobate bismuth materials, through using the barium strontium titanate layer which is mixed with manganese and regulating the respective thickness and the grown conditions of the barium strontium titanate layer which is mixed with the manganese and the barium strontium titanate layer, a barium strontium titanate mixed with the manganese/ zinc niobate bismuth heterogeneous structural material with the high dielectric adjustability and the low dielectric loss property is obtained at the same time.

The invention belongs to the field of electronic material and apparatus, in particular relates to a dielectric adjustable double-phase composite microwave ceramics material. A low-temperature sintering microwave ceramics material disclosed in the invention comprises components with the following weight percentage: 40.0 wt percent to 97.5 wt percent of Ba(1-x)SrxTiO3, 2.5 wt percent to 60.0 wt percent of Zr(1-y)SnyTiO4, as well as 0 wt percent to 15.0 wt percent of ZnO. The invention develops the double-phase composite microwave ceramics material which has the advantages of dielectric constant seriation, low dielectric loss (high Q value) and higher modulation rate under a microwave frequency band and can be used on an adjustable microwave apparatus by carrying out composition to a microwave medium material Zr1-ySnyTiO4 and strontium-barium titanate ferroelectric material.

The utility model belongs to the technical field of electronic materials devices and in particular relates to a low-loss high-dielectric adjustable titanic acid strontium barium ceramic material and a preparation method thereof. The dielectric adjustable titanic acid strontium barium substrate ceramic material is in a single phase cube perovskite structure. The material comprises ingredients with following mass percentage of BaxSr1 to xTiO3 (x = 0.3 to 0.8) of 50 wt. % to 99.9 wt. % and ferrum (Fe) powder of 0.1 wt. % to 50 wt. %. The ferrum powder is added into the titanic acid strontium barium substrate ceramic material of different Ba/Sr ingredients. Thus, the low-loss high-dielectric adjustable titanic acid strontium barium substrate ceramic material is developed and obtained, and the ceramic material can be applied to adjustable parts and especially suitable for materials of microwave medium ceramic ferroelectric phase shifting devices of adjustable microwave parts.

The invention discloses a low-electric-field high-dielectric adjustable zirconium-doped barium ferrite and a preparation method thereof. The zirconium-doped barium ferrite ceramic is a single-phase material, and part of Fe3+in a BaFe12O19 crystal lattice is replaced by Zr4+ to form Fe2+ which is introduced by zirconium doping and coexists in a system, a stable defect dipole pair is formed betweenthe corresponding Fe2+ and the related Fe3+ in the system, and the obtained zirconium-doped barium ferrite ceramic has a high dielectric constant, high dielectric adjustability and an extremely low dielectric adjustable driving electric field on the basis of excellent magnetic performance. According to the invention, a cooperative sintering process of a sol-gel preparation method, air atmosphere and high-oxygen atmosphere is adopted, the process is simple, the controllability is strong, the preparation period is short, the cost is low, and the single-phase zirconium-doped barium ferrite ceramic material with a high dielectric tuning rate under ultra-low modulation voltage can be obtained. The zirconium-doped barium ferrite ceramic has wide application in the fields of dielectric adjustabledevices and magnetic and electric composite multifunctional devices.

The invention belongs to the technical field of electronic materials and devices, and discloses a dielectric adjustable compound microwave ceramic material and a preparation method thereof. The compound microwave ceramic material is prepared by compounding AMP2O7 with BTO. The components of the compound microwave ceramic material and the percentage compositions of the components by weight are as follows based on the total weight of the compound microwave ceramic material: 50.0 to 97.5 percent of BaTiO3; and 2.5 to 50.0 percent of AMP2O7, in which A is Ca or Sr, and M is Zn or Cu. The traditional electronic ceramic preparation process adopted is simple; the cost is low; the material system is environment-friendly without toxicity or side effect; the compound microwave ceramic material has remarkable performance, and is applicable for development and design of adjustable microwave devices.