234 results about "Electromechanical coupling coefficient" patented technology

The invention relates to the technical field of vibrator control, in particular to a driving voltage calibration method and device, electronic equipment, a medium and a program product, and is characterized in that residual vibration parameters and driving frequency of a vibrator are acquired, and the residual vibration parameters comprise a quality factor, an electromechanical coupling coefficient and resonance frequency; based on the residual vibration parameter and the driving frequency, the vibration parameter of the vibrator under the corresponding driving frequency can be calculated, and the vibration parameter can comprise one or more of acceleration, speed and displacement of vibration of the vibrator. The comparison result between the determined vibration parameters of the vibrator under different driving frequencies and the preset vibration parameters serving as the reference can be used for calibrating the driving voltage under the corresponding driving frequency, so that the vibrator is driven by the calibrated driving voltage, and the vibration consistency of the vibrator and the reference vibrator can be ensured.

The invention provides a cavity type bulk acoustic wave resonator with a Bragg reflection layer and a preparation method of the cavity type bulk acoustic wave resonator, and relates to the technical field of bulk acoustic wave resonator manufacturing. The cavity type bulk acoustic wave resonator comprises a first substrate, a bottom electrode, a piezoelectric layer and a top electrode which are stacked in sequence, a cavity is formed between the first substrate and the bottom electrode, the cavity is provided with a plurality of supporting columns, the supporting columns are used for supporting the first substrate and the bottom electrode, each supporting column comprises at least one group of Bragg reflection layers, and the Bragg reflection layers are arranged in the cavity. The Bragg reflection layer is formed by stacking a first material and a second material, and the acoustic impedance of the first material is higher than that of the second material. The cavity type bulk acoustic wave resonator solves the problem that an existing supporting column increases energy loss, and it is guaranteed that the resonator has more stable performance while the electromechanical coupling coefficient is increased.

A ladder type acoustic wave filter is disclosed. The acoustic wave filter can include a plurality of parallel arm resonators and a plurality of series arm resonators, in which an electromechanical coupling coefficient of a parallel arm resonator closest to an input node of the acoustic wave filter among the plurality of parallel arm resonators can be smaller than an electromechanical coupling coefficient of a series arm resonator closest to the input node among the plurality of series arm resonators.

The invention provides a resonator, a filter and electronic equipment. Relates to the technical field of resonators. The resonator can improve the electromechanical coupling coefficient. The resonator comprises a substrate, a first electrode, a plurality of piezoelectric layers and a plurality of second electrodes, the first electrode, the multiple piezoelectric layers and the multiple second electrodes are arranged on the substrate, the multiple piezoelectric layers are provided with first sides and second sides, the multiple second electrodes are located on the first sides and are arranged side by side in the first direction, the first electrodes are located on the second sides, the first sides deviate from the substrate, and the second sides face the substrate; the multiple piezoelectric layers comprise a first piezoelectric layer and a second piezoelectric layer which are stacked; the piezoelectric material of the first piezoelectric layer has a first piezoelectric tensor component e34, the piezoelectric material of the second piezoelectric layer has a second piezoelectric tensor component e34, and the first piezoelectric tensor component e34 and the second piezoelectric tensor component e34 are opposite. By using the piezoelectric layer with opposite piezoelectric tensor components e34, the resonator can have large vibration so as to improve the electromechanical coupling coefficient.

A wafer-level package module includes a first substrate having a first bulk acoustic wave (BAW) device mounted thereon with a first aluminum nitride piezoelectric layer. The wafer-level package module further includes a second substrate having a second BAW device mounted thereon with a second aluminum nitride piezoelectric layer. The first BAW device has a electromechanical coupling coefficient (kt2) different from the second BAW device.

The invention discloses a piezoelectric MEMS transducer and electronic equipment, and relates to the technical field of MEMS. The piezoelectric MEMS transducer comprises a substrate and a piezoelectric layer formed on the substrate, a cavity is further formed in the substrate, a bottom electrode is arranged on the first surface of the piezoelectric layer, and a first differential electrode and a second differential electrode are arranged on the second surface of the piezoelectric layer; the first differential electrodes and the second differential electrodes are alternately distributed on the second surface of the piezoelectric layer in the first direction, and the bottom electrodes are opposite to the first differential electrodes and the second differential electrodes; the piezoelectric layer is a single-crystal lithium niobate film or a single-crystal lithium tantalate film, the first direction serves as the x-axis positive direction of a right-handed coordinate system, the piezoelectric layer has crystal orientation of a target Euler angle, and the square value of the piezoelectric coupling coefficient of the piezoelectric layer in the first direction is larger than or equal to 1.52%. According to the piezoelectric MEMS transducer, the electromechanical coupling coefficient of the piezoelectric MEMS transducer can be improved.

The invention provides a resonator, a filter and electronic equipment. Relates to the technical field of resonators. The resonator can improve the electromechanical coupling coefficient. The resonator can comprise a substrate, a first electrode, a piezoelectric transduction layer and a plurality of second electrodes, the first electrode, the piezoelectric transduction layer and the multiple second electrodes are arranged on the substrate, the piezoelectric transduction layer is provided with a first side and a second side, the multiple second electrodes are located on the first side and are arranged side by side in the first direction, the first electrode is located on the second side, the first side deviates from the substrate, and the second side faces the substrate; the piezoelectric transduction layer comprises a first piezoelectric layer and a second piezoelectric layer which are stacked; the first piezoelectric layer has a first piezoelectric tensor component e33, the second piezoelectric layer has a second piezoelectric tensor component e33, and the first piezoelectric tensor component e33 and the second piezoelectric tensor component e33 are opposite. By using the adjacent piezoelectric layers with opposite piezoelectric tensor components e33, the resonator can have large vibration so as to improve the electromechanical coupling coefficient.

A surface acoustic wave resonator, a filter, a manufacturing method thereof and a communication device. The surface acoustic wave resonator includes a piezoelectric material layer, an interdigital transducer and a dielectric layer; the interdigital transducer is located at a side of the piezoelectric material layer, and the dielectric layer is located between the interdigital transducer and the piezoelectric material layer. Therefore, the surface acoustic wave resonator can reduce the electromechanical coupling coefficient of the surface acoustic wave resonator by arranging the dielectric layer between the interdigital transducer and the piezoelectric material layer. In addition, the surface acoustic wave resonator can adjust the electromechanical coupling coefficient of the surface acoustic wave resonator by controlling the thickness of the dielectric layer.

The invention provides a bulk acoustic wave resonator, a filter and electronic equipment. The bulk acoustic wave resonator comprises a substrate layer, a Bragg reflection layer arranged on the substrate layer and a piezoelectric transduction structure layer arranged on the Bragg reflection layer. The Bragg reflection layer comprises a plurality of film layers which are arranged in a stacked mode, and the refractive indexes of every two adjacent film layers are different; the piezoelectric transduction structure layer comprises a piezoelectric layer and an electrode layer which are stacked; at least one film layer, close to the piezoelectric transduction structure layer, in the Bragg reflection layer is a preset film layer, the preset film layer comprises cavity parts and supporting parts, the cavity parts and the supporting parts are alternately arranged in the first direction, and the first direction is parallel to the substrate layer. According to the bulk acoustic wave resonator, acoustic wave energy is concentrated on the piezoelectric layer through the cavity parts, the electromechanical coupling coefficient of the bulk acoustic wave resonator is increased, under the alternate arrangement of the cavity parts and the supporting parts, the slowness curve of the main vibration mode of the bulk acoustic wave resonator is flattened, the transverse mode and stray response are restrained, and therefore the quality factor of the bulk acoustic wave resonator is improved.

The present disclosure provides a multi-coefficient coupled-mode surface acoustic wave resonator and a manufacturing method therefor. During operation of the surface acoustic wave resonator, at least two different piezoelectric coefficients are coupled and jointly excite acoustic waves. The multi-coefficient coupled-mode surface acoustic wave resonator comprises: a substrate; a piezoelectric layer, provided on the substrate; an electrode unit, provided on the surface of the piezoelectric layer and comprising at least one interdigital electrode pair; and a reflective grating unit, comprising at least two grating structures which are symmetrically arranged on the two sides of the electrode unit, wherein the equivalent density of the electrode unit is greater than 4000kg / m3. The electric field distribution is changed by changing the mass loading effect of the interdigital electrode pair and the ratio of the electrode wavelength to the thickness of the piezoelectric layer, such that at least two piezoelectric coefficients are mutually coupled to jointly excite acoustic waves, thus achieving the surface acoustic wave resonator having an electromechanical coupling coefficient exceeding 25%.

The invention relates to the field of microelectronic devices, in particular to a bulk acoustic wave resonator with a double-layer piezoelectric film structure, a preparation method and a filter, the bulk acoustic wave resonator comprises a cap wafer, and a dry film, a passivation layer, a silicon oxide layer, a high-resistance silicon wafer and RDL metal are sequentially arranged on the cap wafer; the dry film and the cap wafer form a dry film cavity, the passivation layer located above the dry film cavity extends into the dry film cavity, and a top electrode, a first piezoelectric film, a middle electrode, a second piezoelectric film and a bottom electrode are sequentially arranged on the passivation layer; the top electrode and the bottom electrode are used as first ports of the resonator; and the middle electrode is a second port. According to the resonator, the excitation mode of the resonator is changed through cooperation of the two layers of piezoelectric films with the same polarization direction and the intermediate electrode, a high-order resonance mode is jointly excited, meanwhile, a high electromechanical coupling coefficient is kept, and a wide fractional bandwidth is achieved at high frequency through the relatively thick piezoelectric films; the problems that a high-frequency resonator is weak in power bearing capacity, narrow in bandwidth, low in quality factor and poor in stability are solved.

The invention provides a composite piezoelectric layer and a preparation method thereof, and relates to the technical field of semiconductors. The preparation method of the composite piezoelectric layer comprises the following steps: providing a first substrate, and depositing a first piezoelectric layer with a first preset thickness on the first substrate; dividing the surface of the first piezoelectric layer into a plurality of detection areas; detecting the concentration of the doped elements in each detection area; if the concentration of the doping element is larger than the preset doping concentration, the detection area is thinned, a first compensation layer is deposited on the thinned detection area, and the first compensation layer is used for reducing the overall doping concentration of the composite piezoelectric layer on the detection area; if the concentration of the doping element is smaller than the preset doping concentration, a second compensation layer is deposited on the detection area, and the second compensation layer is used for improving the overall doping concentration of the composite piezoelectric layer on the detection area. By adopting the preparation method of the composite piezoelectric layer, the deviation of electromechanical coupling coefficients in different areas on the same piezoelectric layer can be reduced.

The invention relates to the technical field of piezoelectric ceramic materials, in particular to a lead-free piezoelectric ceramic material with a high electromechanical coupling coefficient as well as a preparation method and application of the lead-free piezoelectric ceramic material. The lead-free piezoelectric ceramic material with the high electromechanical coupling coefficient is prepared from the following substrates: (0.99-x) (K < 0.5 > Na < 0.5 >) (N < 0.96 > Sb < 0.04 >) O < 3-0.01 > BaZrO < 3-x > Bi < 0.5 > (Ag < 0.5 > Li < 0.5 >) < 0.5 > HfO < 3 >. The lead-free piezoelectric ceramic material with the high electromechanical coupling coefficient has excellent electrical properties, KP of the lead-free piezoelectric ceramic material can reach 57%, d33 of the lead-free piezoelectric ceramic material can reach 462 pC / N, and therefore the lead-free piezoelectric ceramic material can be applied to the industry. The preparation process of the lead-free piezoelectric ceramic material with the high electromechanical coupling coefficient is safer, and the lead-free piezoelectric ceramic material does not contain toxic substances such as lead element and methylbenzene.

The invention provides an acoustic resonator, a filter and electronic equipment. The acoustic resonator comprises a substrate layer, a piezoelectric transduction structure layer and an energy adjusting layer, the piezoelectric transduction structure layer is arranged on one side of the substrate layer; the energy adjusting layer is arranged between the substrate layer and the piezoelectric transduction structure layer, the energy adjusting layer comprises a plurality of binding grooves, and each binding groove at least penetrates through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer. Through the binding grooves which are arranged at intervals and penetrate through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer, sound wave energy is concentrated on the piezoelectric transduction structure layer, leakage of the sound wave energy towards the substrate layer is reduced, and the electromechanical coupling coefficient of the acoustic resonator is improved; the piezoelectric transduction structure layer is supported, collapse of the piezoelectric transduction structure layer is avoided, the situation that the power capacity of the acoustic resonator is reduced is reduced, and therefore the power capacity and the electromechanical coupling coefficient of the acoustic resonator are improved.

A surface acoustic wave device has a piezoelectric substrate having a cut angle (e.g., the piezoelectric angle is cut so as to have a crystal orientation) that allows the surface acoustic wave device to operate as a longitudinally leaky surface acoustic wave device that confines the acoustic wave energy within the piezoelectric substrate and that has less propagation attenuation and a higher electromechanical coupling coefficient k2.

Bulk acoustic wave resonators are presented. Such resonators typically operate based on a dynamic nonuniform effective piezoelectricity in composite multilayer ferroelectrics with large electrostriction coefficients, like barium strontium titanate (BST). Harmonic resonance modes of a multilayer bulk acoustic wave resonator can be selectively excited with an electromechanical coupling coefficient equal to the fundament mode, which is contrary to the trend K2∝1 / n2 exhibited by conventional piezoelectric bulk acoustic resonators. Such a resonator allows for the design of a new class of band-switching filters.

The invention discloses a piezoelectric ceramic with high Curie temperature and high temperature stability and a preparation method thereof, the composition general formula of the piezoelectric ceramic is xPb (In1 / 2Nb1 / 2) O3-yPbZrO3-(1-x-y) PbTiO3, the value range of x is 0.20-0.50, and the value range of y is 0.10-0.30. The high Curie temperature, the large piezoelectric coefficient and the high coercive field are achieved, the temperature stability of the excellent piezoelectric property at the room temperature to 300 DEG C is achieved, the change rate of the inverse piezoelectric coefficient within the range from the room temperature to 180 DEG C is only 1.4%, and the change rate of the electromechanical coupling coefficient kp within the temperature range from the room temperature to 275 DEG C is only 4.2%.

The invention relates to the technical field of radio frequency filters, in particular to a 13GXBAR filter design method based on a lithium niobate film. The Euler angle of the lithium niobate thin film is subjected to simulation setting in finite element simulation software, admittance responses under different cutting angles are obtained, an admittance curve with a large electromechanical coupling coefficient and complete stray mode suppression is obtained, the tangential angle is used for simulating an electrode material, the interdigital logarithm, the interdigital distance, the thin film thickness and the metallization ratio, and an admittance curve with a large electromechanical coupling coefficient and complete stray mode suppression is obtained. The method comprises the following steps of: constructing a plurality of resonators, obtaining impedance of each resonator, obtaining material parameters of the corresponding resonator, constructing a three-dimensional force-electricity coupling model of the lithium niobate resonator, carrying out layout design on the physical model in finite element simulation software through a field-circuit coupling method, and coupling force-electricity-sound multi-physical fields to obtain an S parameter curve of the designed XBAR filter; and whether the S parameter result is consistent with the target is verified, so that the forward design of full-simulation driving is realized.

The invention relates to the technical field of semiconductors, in particular to an acoustic resonator, an acoustic filter and an acoustic filter module. The acoustic resonator at least comprises a piezoelectric film and an interdigital electrode; a preset crystal axis in the piezoelectric film serves as a first reference axis, the normal direction of the interdigital electrode pair serves as a second reference axis, and a preset included angle is formed between the first reference axis and the second reference axis; the average tangential direction of the first gap track and the average tangential direction of the second gap track in the interdigital electrode meet a preset condition. The electromechanical coupling coefficient of the acoustic resonator is adjusted by changing the acoustic wave propagation direction in the acoustic wave surface. Moreover, by designing a first gap track tangential angle and a second gap track tangential angle, the electromechanical coupling coefficient of the acoustic resonator is changed, and energy leakage caused by an overlarge energy flow incident angle is avoided. Therefore, acoustic wave resonators with different electromechanical coupling coefficients can be realized on the same piezoelectric film, and then acoustic wave filters with different relative bandwidths are realized.

Methods for improving the electromechanical coupling coefficient and bandwidth of micromachined ultrasonic transducers, or MUTs, are presented as well as methods of manufacture of the MUTs improved by the presented methods.

The invention relates to the technical field of bulk acoustic wave resonators, and particularly provides a bulk acoustic wave resonator and a design method thereof, and the method comprises the steps: determining the scandium doping concentration and thickness corresponding to a plurality of piezoelectric layers according to a target effective electromechanical coupling coefficient and a target resonator frequency, determining an electrode material and corresponding acoustic impedance according to the target loss performance; for each piezoelectric layer, acoustic parameters, piezoelectric coupling parameters and static capacitance parameters are calculated according to the corresponding scandium doping concentration and thickness, and the acoustic parameters comprise acoustic impedance; calculating the interface impedance of the adjacent layer structures according to the acoustic impedance of the adjacent layer structures; inputting all the acoustic parameters, all the static capacitance parameters, all the piezoelectric coupling parameters, the electrode material and all the interface impedance into a Mason model to complete the design of the bulk acoustic wave resonator; according to the method, the Mason model can comprehensively consider the influence of the physical parameter difference of a plurality of piezoelectric layers on the bulk acoustic wave resonator and the interfacial effect between the layer structures.

The invention discloses a lithium niobate acoustic superlattice bulk acoustic wave resonator device based on an inclined domain structure and a design method thereof.The bulk acoustic wave resonator device comprises an upper surface electrode, a lithium niobate acoustic superlattice and a lower surface electrode which are sequentially stacked from top to bottom, the lithium niobate acoustic superlattice comprises positive domain regions and negative domain regions which are alternately arranged, and the positive domain regions and the negative domain regions are alternately arranged. And the positive domain region and the negative domain region are inclined domains. The invention also provides a design method of the bulk acoustic wave resonance device, which comprises the following steps of: firstly, acquiring simulation parameters through numerical simulation, and then designing different cut types of lithium niobate acoustic superlattices with positive domain regions and negative domain regions which are periodically and alternately arranged and inclined structures according to the simulation parameters; and finally, respectively selecting proper electrodes on the upper surface and the lower surface of the lithium niobate acoustic superlattice to form the bulk acoustic wave resonator. The bulk acoustic wave resonator is simple in structure, and has more working resonance modes and a higher electromechanical coupling coefficient.

System and methods for a hollow-disk radial-contour mode resonator structure. The hollow disk reduces the dynamic mass and stiffness of the structure. Since electromechanical coupling Cx / Co goes as the reciprocal of mass and stiffness, the hollow disk structure has a considerably stronger electromechanical coupling than a solid one at the same frequency, and thus raises Cx / Co without excessive gap-scaling. Several embodiments of hollow disk resonators are detailed, including asymmetric and symmetric disk configurations.

The invention relates to a method for producing a perovskite-type single crystal, and a perovskite-type single crystal. Provided are: a single crystal which exhibits a high electromechanical coupling coefficient and a high coercive field when used in a piezoelectric element; and a method for producing the single crystal. The method is a method for producing a perovskite-type single crystal, in which a first single crystal of a perovskite type is prepared by firing a raw material containing an acceptor in an air atmosphere, a step (2) including firing the first single crystal in a reducing atmosphere, and a step (3) including firing the single crystal prepared in step (2) in an air atmosphere, in this order, a perovskite-type single crystal having a higher coercive field value than a first single crystal is prepared.

The invention relates to the technical field of communication equipment design, in particular to a design method and system for a broadband annular magnetoelectric antenna with a high electromechanical coupling coefficient. Constructing a vibration analysis model of the annular piezoelectric layer, and calculating to obtain a characteristic equation of rigidity and mass coefficients according to the vibration analysis model; solving the characteristic equation of the rigidity and the quality coefficient to obtain a resonant frequency and an anti-resonant frequency; the resonant frequency and the anti-resonant frequency are substituted into an electromechanical coupling coefficient formula, a size factor is introduced, and a correction formula is constructed; obtaining an optimized size parameter of the annular piezoelectric layer based on a correction formula; optimized size parameters of the annular piezoelectric layer can be obtained through simulation, the design efficiency and the performance stability of the antenna are further improved, and in practical application, the antenna can adapt to the requirements of different frequency bands and scenes more quickly.

The invention discloses a bulk acoustic wave resonance device, a forming method thereof and a filter. The middle layer is located on the substrate, and the middle layer comprises a cavity and a plurality of defect sub-layers with crystal defects; the piezoelectric layer is located on the middle layer, the piezoelectric layer comprises a first side and a second side which are opposite to each other, and the middle layer and the substrate are located on the first side; the first electrode layer is located on the first side of the piezoelectric layer; the second electrode layer is located on the second side of the piezoelectric layer, and the projection of the first electrode layer and the projection of the second electrode layer towards the direction of the substrate have an overlapped area. The crystal defect in the middle layer can form a charge trap, and a conductive plane can be prevented from being formed on the surface of the substrate, so that the generated parasitic coupling phenomenon is effectively inhibited, the electric loss is reduced, and the Q value of the resonance device or the electromechanical coupling coefficient (Kt) of the resonance device is improved.

The present invention provides a surface acoustic wave resonator and a manufacturing method thereof, and a surface acoustic wave filter, which have high quality factor Q, high electromechanical coupling coefficient, good TCF characteristics and power resistance. The surface acoustic wave resonator of the present invention comprises: a composite piezoelectric substrate, the composite piezoelectric substrate having: an LGS base layer, the LGS base layer is formed of single crystal LGS, and a GaN piezoelectric layer formed on the LGS base layer, the thickness of the GaN piezoelectric layer does not exceed 20 times the wavelength of the acoustic wave propagating in the surface acoustic wave resonator; and interdigital electrodes formed on the GaN piezoelectric layer.

The invention belongs to the technical field of functional materials, and particularly relates to a 1-3 type lead metaniobate piezoelectric composite material and a preparation method and application thereof. The composite material takes lead metaniobate ceramic with a tungsten bronze structure as a one-dimensional piezoelectric phase and takes epoxy resin as a three-dimensional polymer phase. The ratio [lambda] / T of the transverse periodic dimension ([lambda]) of the ceramic column to the thickness (T) of the composite material is 0.1-0.6. The preparation method is characterized in that the ceramic column array is formed through precise cutting, cutting parameters are controlled to achieve the lambda / T ratio, and then resin encapsulation, curing, polishing and electrode preparation are conducted. According to the invention, the electromechanical coupling performance and stability of the composite material at ultrahigh temperature are synergistically improved by selecting the lead metaniobate ceramic with high Curie temperature and combining specific lambda / T structural parameters. The obtained material can still keep good performance at 350 DEG C, the maximum thickness electromechanical coupling coefficient kt can reach 0.35, and the material is suitable for high-temperature acoustic logging and underwater acoustic receiving transducers.

The invention relates to the technical field of microelectronics, in particular to an acoustic wave filter and a preparation method thereof. The acoustic wave filter comprises at least one series resonator and at least one parallel resonator; each of the series resonator and the parallel resonator comprises a supporting substrate, a dielectric layer, a piezoelectric layer and an interdigital electrode; the dielectric layer and the piezoelectric layer are located on the supporting substrate, and a preset distance exists between the bottom of the piezoelectric layer and the supporting substrate; the interdigital electrode is arranged at the top of the piezoelectric layer; and a bottom electrode is arranged between the support substrate and the piezoelectric layer of at least one of the series resonator and the parallel resonator. The target mode is selected by selecting whether a bottom electrode exists or different in-plane orientations exist, so that local thinning of the piezoelectric layer is avoided, the advantages of a high-order sound wave mode in the aspects of high sound velocity and large electromechanical coupling coefficient are fully utilized, and batch production of high-performance high-frequency filters and yield improvement are facilitated.

This invention provides a method for manufacturing a bulk acoustic wave resonator, including a substrate provision step, an acoustic reflection structure formation step, and a stacked structure formation step. The stacked structure formation step includes: sequentially forming a lower electrode, a first piezoelectric layer, a second piezoelectric layer, and an upper electrode from bottom to top on the substrate or the acoustic reflection structure. The upper electrode, the second piezoelectric layer, the first piezoelectric layer, the lower electrode, and the acoustic reflection structure have an overlapping region in the device thickness direction, which constitutes the resonant region of the bulk acoustic wave resonator. The first piezoelectric layer is implemented using a doped piezoelectric material, which is doped with impurity elements to improve the electromechanical coupling coefficient of the first piezoelectric layer. The second piezoelectric layer is implemented using an undoped piezoelectric material. Correspondingly, this invention also provides a bulk acoustic wave resonator and a filter. Implementing this invention can yield a bulk acoustic wave resonator that balances electromechanical coupling coefficient and quality factor, has low parasitic modes, and exhibits stress balance.