Patent classifications
H10N30/092
METHOD OF MANUFACTURING FLEXIBLE LARGE-AREA PIEZOELECTRIC COMPOSITE MATERIALS
Proposed is a method of manufacturing a piezoelectric composite material. The method includes the steps: wet mixing the ceramic powder, the polymer binder, the plasticizer, and the solvent for 4 to 72 hours to produce the mixed slurry, in which the amount of the polymer binder in the mixed slurry is 3 to 10 parts by weight, the amount of the plasticizer is 0.1 to 3 parts by weight, and the amount of the solvent is 30 or more to less than 50 parts by weight, based on 100 parts by weight of the ceramic powder in the mixed slurry; introducing the mixed slurry into a tape casting process to produce a piezoelectric composite sheet; drying and molding the piezoelectric composite sheet in a roll-to-roll process to form a molded piezoelectric composite sheet; laminating and compressing piezoelectric composite sheets molded to produce piezoelectric composite sheet laminates; and cutting the piezoelectric composite sheet laminate into the desired shape and size.
FLEXIBLE VIBRATION MODULE AND DISPLAY APPARATUS INCLUDING THE SAME
A flexible vibration module is disclosed. The flexible vibration module includes a piezoelectric composite layer, including: a plurality of piezoelectric portions each having a piezoelectric characteristic, where at least two of the plurality of piezoelectric portions have different sizes; and a flexible portion between the plurality of piezoelectric portions.
Piezoelectric member, ultrasonic oscillation element, ultrasonic probe, ultrasound diagnostic system, and method for producing piezoelectric member
A piezoelectric member including metal electrodes with improved adhesiveness to piezoelectric elements is to be provided. A piezoelectric member 102 includes a piezoelectric element 21, and a pair of electrodes 41, 42 respectively formed on a pair of opposing surfaces 21b, 21c of the piezoelectric element 21. The electrodes 41, 42 includes: a base film 41a that is formed on the opposing surfaces 21b, 21c of the piezoelectric element 21 and contains a thiol group; a metal adhesive film 41b formed on the base film 41a; and an electrode film 41c that is formed on the metal adhesive film 41b and is for applying voltage to the piezoelectric element 21. The metal adhesive film 41b is formed with a different material from the electrode film 41c, and has a thickness of 1 to 10 nm.
ELECTRIC FIELD-VIBRATION GENERATING TRANSDUCER HAVING PIEZOELECTRIC MATERIAL OF HIGH DEGREE OF DISPLACEMENT, AND MANUFACTURING METHOD THEREOF
Provided is an electric field-vibration generating transducer having a piezoelectric material of a high degree of displacement, and a manufacturing method thereof. The electric field-vibration generating transducer lowers the cost of production through miniaturization simultaneously with realizing excellent generating characteristics of the electric field-vibration generating transducer based on high efficiency and low voltage driving because the piezoelectric material of the high degree of displacement (high strain piezoelectrics) having a high piezoelectric constant (d.sub.33=1,000 to 6,000 pC/N), a high dielectric constant (K.sub.3.sup.T=6,000 to 15,000) as well as a low dielectric loss (tan δ<2%) is applied thereto, so the electric field-vibration generating transducer may accelerate the movement of a material, a chemical action, and a biological reaction, and may be applied to a medical device for the purpose of treatment for tumors aimed at human bodies and animals.
POLYMER-BASED PIEZOELECTRIC COMPOSITE MATERIAL FILM
Provided is a polymer-based piezoelectric composite material film which has high conversion efficiency and is capable of reproducing a sound with a sufficient volume. The polymer-based piezoelectric composite material film is a film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and two electrode layers which are laminated on both surfaces of the polymer-based piezoelectric composite material, in which a coefficient of variation of intensity ratio α.sub.1 of (002) plane peak intensity and (200) plane peak intensity derived from the piezoelectric particles=(002) plane peak intensity/((002) plane peak intensity+(200) plane peak intensity) in a case where the polymer-based piezoelectric composite material is evaluated by an X-ray diffraction method is less than 0.3.
METHOD FOR MANUFACTURING FLEXIBLE LAMINATED PIEZOELECTRIC COMPOSITE
Disclosed is a method for manufacturing a laminated piezoelectric composite. The method includes wet-mixing ceramic powder, a polymer binder, a plasticizer and a solvent for 4 to 72 hours so as to generate a mixed slurry, introducing the mixed slurry into a tape casting process so as to prepare a plurality of piezoelectric composite sheets, drying and forming the plurality of piezoelectric composite sheets using a roll-to-roll process so as to prepare the plurality of formed piezoelectric composite sheets, forming internal electrodes on the plurality of piezoelectric composite sheets so as to prepare the plurality of piezoelectric composite sheets having the internal electrodes, laminating and pressing the plurality of piezoelectric composite sheets having the internal electrodes so as to generate a piezoelectric composite sheet laminate having the internal electrodes, and cutting the piezoelectric composite sheet laminate having the internal electrodes into a desired shape and size.
Metal stack templates for suppressing secondary grains in sca1n
A metal stack for templating the growth of AlN and ScAlN films is disclosed. The metal stack comprises one, two, or three layers of metal, each of which is compatible with CMOS post-processing. The metal stack provides a template that promotes the growth of highly textured c-axis {002} AlN and ScAlN films. The metal stacks include one or more metal layers with each metal layer having either a hexagonal {002} orientation or a cubic {111} orientation. If the metal stack includes two or more metal layers, the layers can alternate between hexagonal {002} and cubic {111} orientations. The use of ScAlN results in a higher piezoelectric constant compared to that of AlN for ScAlN alloys up to approximately 44% Sc. The disclosed metal stacks resulted in ScAlN films having XRD FWHM values of less than approximately 1.1° while significantly reducing the formation of secondary grains in the ScAlN films.
PIEZOELECTRIC POLYMER BLEND AND COMPOSITE COMPOSITIONS INCLUDING LITHIUM-DOPED POTASSIUM SODIUM NIOBATE
A polymer composite exhibiting piezoelectric properties can be formed for flexible and/or thin film applications, in which the polymer composite includes a polymer matrix and a piezoelectric ceramic filler embedded in the polymer matrix. The polymer matrix may include at least two polymers: a first polymer and a second polymer. The first polymer may be a fluorinated polymer, and the second polymer may be compatible with the first polymer and have a dielectric constant of less than approximately 20. The piezoelectric ceramic filler can be lithium doped potassium sodium niobite (KNLN), and be approximately 40-70% by volume of the polymer composite. The remaining 30-60% by volume may be the polymer matrix, which may itself be approximately 5-20% by weight second polymer and 80-95% fluorinated polymer.
PIEZOELECTRIC POLYMER BLEND AND COMPOSITE COMPOSITIONS INCLUDING LITHIUM-DOPED POTASSIUM SODIUM NIOBATE
A polymer composite exhibiting piezoelectric properties can be formed for flexible and/or thin film applications, in which the polymer composite includes a polymer matrix and a piezoelectric ceramic filler embedded in the polymer matrix. The polymer matrix may include at least two polymers: a first polymer and a second polymer. The first polymer may be a fluorinated polymer, and the second polymer may be compatible with the first polymer and have a dielectric constant of less than approximately 20. The piezoelectric ceramic filler can be lithium doped potassium sodium niobite (KNLN), and be approximately 40-70% by volume of the polymer composite. The remaining 30-60% by volume may be the polymer matrix, which may itself be approximately 5-20% by weight second polymer and 80-95% fluorinated polymer.
METHODS OF FORMING PIEZOELECTRIC MATERIALS, PIEZOELECTRIC DEVICES, AND ASSOCIATED TOOLING AND SYSTEMS
A method of forming a piezoelectric device may include depositing a sol-gel film over a substrate and curing the sol-gel film by impinging light onto an exposed surface of the sol-gel film to form a piezoelectric ceramic element. The method may produce a piezoelectric composite material including at least two piezoelectric ceramic pillars over the substrate. The at least two piezoelectric pillars may include at least one layer. The at least one layer having a gradient density, such that a first portion of the at least one layer proximate the substrate has a density lower than a second portion that is located a greater distance from the substrate than the first portion. The piezoelectric composite material may further include a resin separating the at least two piezoelectric ceramic pillars.