2486 results about "Barium titanate" patented technology

A multilayer ceramic substrate having a thin film structure containing capacitor connected thereto is provided as an interposer capacitor, the capacitor employing platinum as the bottom electrode of the capacitor. In a preferred capacitor, a dielectric material such as barium titanate is used as the dielectric material between the capacitor electrodes. The fabrication of the interposer capacitor requires an in-situ or post deposition high temperature anneal and the use of such dielectrics requires heating of the capacitor structure in a non-reducing atmosphere. A layer of a high temperature, thin film diffusion barrier such as TaSiN on the lower platinum electrode between the electrode and underlying multilayer ceramic substrate prevents or minimizes oxidization of the metallization of the multilayer ceramic substrate to which the thin film structure is connected during the fabrication process. A method is also provided for fabricating an interposer capacitor with a multilayer ceramic substrate base and a thin film multilayer structure having at least one capacitor comprising at least one bottom platinum electrode.

Provided here is a method of producing a monolithic body from a porous matrix, comprising: (i) providing a porous matrix having interstitial spaces and comprising at least a first reactant; (ii) contacting the porous matrix with an infiltrating medium that carries at least a second reactant; (iii) allowing the infiltrating medium to infiltrate at least a portion of the interstitial spaces of the porous matrix under conditions that promote a reaction between the at least first reactant and the at least second reactant to provide at least a first product; and (iv) allowing the at least first product to form and fill at least a portion of the interstitial spaces of the porous matrix, thereby producing a monolithic body, wherein the monolithic body does not comprise barium titanate.

An ultrafine powder of barium titanate including solid solutions and doped compounds that meets up to specific characteristics is produced by method comprising two main steps. The first step is a reaction, typically in a Segmented Flow Tubular Reactor, between reactants to produce cubic-structure barium titanate composed of non-agglomerated ultrafine particles having a shape of given aspect ratio, usually a generally spherical shape, of low density corresponding at most to 90% of the intrinsic density, all particles being smaller than 1 micron and having a narrow particle size distribution and wherein the ratio of Ba:Ti including substitutents and dopants is very close to the ideal stoichiometry. This is followed by subjecting the powder produced in the first step to a second stage solvothermal post treatment typically in an autoclave at temperature less than 400° C. to convert the cubic-structure particles of low density to ultrafine tetragonal particles of increased density corresponding to at least 90% of the intrinsic density while maintaining the same aspect ratio, and maintaining the size of all particles below 1 micron, the narrow particle size distribution span, and the given ideal stoichiometry. The produced particles can have a non-spherical facetted shape such as cube-like.

Methods for improved manufacture of green biodiesel focus on the selection and use of one or more solid metallic oxide base catalyst(s) selected from the group consisting of calcium oxide (CaO), calcium aluminum oxide (CaO—Al2O3), calcium titanate (CaTiO3), barium titanate (BaTiO3), magnesium aluminum oxide (MgO—Al2O3), zinc oxide (ZnO), copper (II) oxide (CuO), nickel oxide (NiO), manganese oxide (MnO), titanium oxide (TiO), vanadium oxide (VO), cobalt oxide (CoO), iron oxide (FeO), chromite (FeCr2O4), hydrotalcite (Mg6Al2(CO3)(OH)16.4(H2O), magnetite (Fe3O4), magnesium silicate and calcium silicate.

The invention discloses a modified zirconium oxide ceramic material. The modified zirconium oxide ceramic material comprises the following components in percentage by molar concentration: 0-6mol% of yttrium oxide, 0-15mol% of cerium oxide, 0.02-1mol% of titanium oxide, 0-20mol% of aluminum oxide, 0-5mol% of barium titanate and the balance of zirconium oxide. The invention also discloses zirconium oxide ceramic and a dielectric cover plate prepared from the modified zirconium oxide ceramic material. The dielectric cover plate prepared from the modified zirconium oxide ceramic material has the advantages of high hardness, good toughness, high strength and high dielectric constant.

High-capacity capacitors and gate insulators exhibiting moderately high dielectric constants with surprisingly low leakage using amorphous or low temperature films of perovskite type oxides including a titanate system material such as barium titanate, strontium titanate, barium strontium titanate (BST), lead titanate, lead zirconate titanate, lead lanthanum zirconate titanate, barium lanthanum titanate, a niobate, aluminate or tantalate system material such as lead magnesium niobate, lithium niobate lithium tantalate, potassium niobate and potassium tantalum niobate, a tungsten-bronze system material such as barium strontium niobate, lead barium niobate, barium titanium niobate, and Bi-layered perovskite system material such as strontium bismuth tantalate, bismuth titanate deposited directly on a silicon surface at temperatures about 450° C. or less.

The invention provides dielectric compositions and methods of forming the same. The dielectric compositions may be used to form dielectric layers in electronic devices such as multilayer ceramic capacitors (MLCCs) and, in particular, MLCCs which include base metal electrodes. The dielectric compositions include a barium titanate-based material and several dopants. The type and concentration of each dopant is selected to provide the dielectric composition with desirable electrical properties including a stable capacitance over a temperature range, a low dissipation factor, and a high capacitance. Preferably, MLCCs including dielectric layers formed with the composition satisfy X7R and / or X5R requirements.

An enhanced piezoelectric wire structure includes an elongated portion of piezoelectric material, a metallic core, and an outer conductive sheath. The metallic core is substantially surrounded by the elongated portion of piezoelectric material and configured to function as a first electrode for the piezoelectric structure. The conductive outer sheath preferably covers selected areas of the elongated portion of piezoelectric material and functions as a second electrode for the structure. The piezoelectric material may correspond to barium titanate ceramic fibers, such that a lead-free structure is effected, however other piezoelectric materials may also be utilized. The disclosed structure can be poled with a reduced poling voltage and lower temperature level, and also requires a reduced voltage potential level required for mechanical actuation. A collection of such piezoelectric structures can be provided together in a modular patch assembly that may be formed in a variety of customized configurations for integration with various environments, and can function as a mechanical actuator device, a condition-responsive device (e.g., a sensor) and / or as a power generation device. When utilized as a power generation device, the subject piezoelectric assembly can power tire electronics components such as a revolution counter, a sensor, a rechargeable battery, a flashing light assembly, a microcontroller, a global positioning system (GPS), and a radio frequency (RF) device.

The present invention provides a process for preparing an aluminum-titanate-based sintered body comprising the step of firing, at 1250 to 1700° C., a formed product prepared from a raw material mixture containing 100 parts by weight of a mixture of TiO2 and Al2O3 in a weight ratio of TiO2:Al2O3=40:60 to 60:40, and 1 to 15 parts by weight of an alkali feldspar represented by the formula:(NaxK1-x)AlSi3O8 wherein 0<=x<=1. According to the process of the present invention, it is possible to obtain an aluminum-titanate-based sintered body in which inherent properties of an aluminum titanate, i.e., a low coefficient of thermal expansion and high corrosion resistance are maintained, the mechanical strength thereof is improved, and which can be stably used even under high temperature conditions.

A multilayer ceramic capacitor containing dielectric layers, in which each of the dielectric layers has a main component containing barium titanate, a first auxiliary component containing at least one kind selected from MgO, CaG, BaO, and SrO, a second auxiliary component containing a silicon oxide as a main component, a third auxiliary component containing at least one kind selected from the group consisting of V2O5, MoO3, and WO3, a fourth auxiliary component containing an oxide of at least one kind of first rare-earth element (R1) selected from Sc, Er, Tm, Yb, and Lu, a fifth auxiliary component containing CaZrO3 or a mixture (CaO+ZrO2) of CaO and ZrO2, and a liquid phase addition of organic metal salts of Zr and Ca.

A low-temperature hydrothermal reaction is provided to generate crystalline perovskite nanotubes such as barium titanate (BaTiO3) and strontium titanate (SrTiO3) that have an outer diameter from about 1 nm to about 500 nm and a length from about 10 nm to about 10 micron. The low-temperature hydrothermal reaction includes the use of a metal oxide nanotube structural template, i.e., precursor. These titanate nanotubes have been characterized by means of X-ray diffraction and transmission electron microscopy, coupled with energy dispersive X-ray analysis and selected area electron diffraction (SAED).

Multilayer ceramic chip capacitors (MLCC's) which satisfy X7R TCC requirements and which are compatible with silver-palladium internal electrodes. The MLCC's exhibit desirable dielectric properties—high capacitance, low dissipation factor, high insulation resistance, stable TCC—and excellent performance on highly accelerated life testing, and good resistance to dielectric breakdown. The dielectric layers comprise a lead-free and cadmium-free barium titanate base material doped with other metal oxides such oxides of zinc, boron, bismuth, barium, titanium, praseodymium, cerium, tungsten, neodymium, tungsten, tin, niobium, copper, and / or manganese in various combinations. The dielectric ceramic materials herein can be fired at less than 1150° C. with an inner electrode having 70 wt % or more Ag and 30 wt % or less Pd to form an MLCC.

The process of synthesizing composite polyimide / nanometer barium titanate film with high dielectric constant includes the following steps: adding maleic anhydride and diamine in the same molar amount into N-methyl-2-pyrrolidone or N, N-dimethyl acetamide as solvent to compound solution with solid content of 10-20 %, adding nanometer modifying barium titanate particle in the amount less than 40 % of the composite film weight into the solution and ultrasonically dispersing, stirring continuously at room temperature for 18-24 hr to obtain polyamic acid, pouring the polyamic acid on glass plate mold, and vacuum heating to eliminate solvent and iminate to obtain the composite polyimide / nanometer barium titanate film. Thus prepared film has excellent heat stability, high oxidative degradation resistance, high dielectric constant and low dielectric loss, and may be used for wound film capacitor, printed circuit board, semiconductor device, etc.