216 results about "Lithium tantalate" patented technology

The invention relates to a czochralski method-based crystal growth interface shape detection method and device. The method comprises the steps that: a seed crystal temperature T and an interface electromotive force U at the same time in a crystal growth process are collected, and a T-U curve of the interface electromotive force U changing with the seed crystal temperature T is obtained; the change trend of the shape of a crystal growth interface in real time is judged by observing the deviation between the T-U curve and a reference line, wherein the reference line is a straight line passing through the starting point of the T-U curve, and the slope of the straight line is the Seebeck coefficient of the crystal. The invention also relates to a device used by the method. The detection method provided by the invention can detect the change trend of the shape of the crystal growth interface in real time in the crystal growth process, and can be applied to Czochralski method growth equipment for various single crystals such as lithium niobate, lithium tantalate, sapphire, yttrium aluminum garnet and the like.

The invention belongs to the field of semiconductor materials, and particularly relates to a method for improving film thickness uniformity of a lithium tantalate bonding wafer, which comprises the following steps: thinning the lithium tantalate bonding wafer; and according to the film thickness distribution of the thinned lithium tantalate bonding wafer, pressurizing the polished bonding wafer in different areas step by step, fitting a polishing rate model according to the film thickness measured in real time, and adjusting a pressurizing formula for polishing. Whether the final shutdown thickness is reasonable or not is judged through a polishing rate model, compensation is obtained, and then secondary polishing is conducted. The consistency of supplied materials before polishing is guaranteed through thinning processing, and a foundation is provided for improving the thickness uniformity of a polishing film; the thickness uniformity of the film in the bonding sheet is ensured by pressurizing step by step in different regions; and the polishing rate model ensures the film thickness uniformity between the bonding sheets.

An acoustic wave device includes a support substrate, first and second piezoelectric layers, and an IDT electrode. The first and second piezoelectric layers are on the support substrate. The IDT electrode is on the first piezoelectric layer and includes electrode fingers. The second piezoelectric layer is between the first piezoelectric layer and the support substrate. The first and second piezoelectric layers are made of lithium tantalate or lithium niobate. Euler angles of the second piezoelectric layer are different from Euler angles of the first piezoelectric layer.

An acoustic wave device includes a piezoelectric layer including lithium tantalate or lithium niobate, a dielectric film on the piezoelectric layer, the dielectric film including a dielectric material having a higher dielectric constant than that of the lithium tantalate or lithium niobate, and an IDT electrode on the dielectric film.

The invention discloses a bulk acoustic wave filter, a preparation method thereof and a radio frequency module. The bulk acoustic wave filter includes at least: a substrate; the first film layer is located on one side of the substrate, the first film layer comprises a first area and a second area surrounding the first area, and a photosensitive dry film surrounding the first area is arranged in the second area; the piezoelectric film is positioned on one side, far away from the substrate, of the first film layer; wherein the piezoelectric film comprises a lithium niobate film and / or a lithium tantalate film; and the substrate, the photosensitive dry film and the piezoelectric film jointly form a cavity. According to the bulk acoustic wave filter, the photosensitive dry film is introduced and serves as the supporting layer and the sacrificial layer, the effect of supporting the lithium niobate thin film and / or the lithium tantalate thin film is achieved, and the effect of sacrificing part of the photosensitive dry film to form the cavity is achieved; and meanwhile, by utilizing the flexibility of the photosensitive dry film, the limitation on the lithium niobate and / or lithium tantalate crystal phase can be reduced, so that the application range of the lithium niobate film and / or lithium tantalate film in the radio frequency communication field is widened.

The invention relates to a thin film electro-optical crystal-silicon nitride heterogeneous integrated N * N high-speed optical switch array and a preparation method thereof. The thin film electro-optical crystal-silicon nitride heterogeneous integrated N * N high-speed optical switch array is formed by connecting 1 * 2 or 2 * 2 Mach-Zehnder high-speed optical switch units according to a certain topological structure. Wherein the high-speed optical switch unit is composed of a silicon nitride passive waveguide and a thin-film electro-optical crystal / silicon nitride heterogeneous integrated phase shift region. Comprising but not limited to thin-film lithium niobate, thin-film lithium tantalate, barium titanate and lead zirconate titanate is integrated above the silicon nitride phase shifting arm through a micro transfer printing method to form a heterogeneous integrated phase shifting region. The large-scale high-speed optical switch array with excellent performance is realized by combining the characteristics of ultra-low loss, CMOS compatibility, thermal stability and the like of a silicon nitride material, the characteristics of low power consumption, low loss, high-speed modulation and the like of a thin film electro-optical crystal and the advantages of high flexibility, parallel integration, low cost, low loss and the like of a micro transfer printing method.

The invention belongs to the technical field of sensors, and particularly relates to a liquid phase sensor based on longitudinal surface acoustic waves and a preparation method and application thereof. The liquid phase sensor based on the longitudinal surface acoustic wave comprises a delay line type surface acoustic wave device and a sensitive element, the delay line type surface acoustic wave device comprises a substrate, a temperature compensation layer and a piezoelectric layer which are arranged in a stacked mode, an interdigital transducer is arranged on the surface of the piezoelectric layer, and the piezoelectric layer is made of tangential lithium niobate or lithium tantalate single crystals. A high-speed longitudinal surface acoustic wave (LSAW) mode without body wave leakage is excited by adopting a heterogeneous acoustic layer structure of an interdigital electrode / a piezoelectric thin layer / a temperature compensation layer / a high-sound-velocity substrate, and a delay line type low-loss and high-sensitivity sensor for a liquid phase is constructed by utilizing the LSAW. Compared with a traditional rayleigh and love mode SAW sensor, the LSAW-based sensor has the advantages that the attenuation coefficient is greatly reduced, the sensitivity is greatly improved, and the LSAW-based sensor has a good application prospect in a liquid phase environment.

An interface for an optical modulator and the optical modulator are described. The interface includes first and second differential line pairs. The first differential line pair has a first negative line and a first positive line arranged on opposing sides of a first waveguide. The first negative line is on a distal side of the first waveguide relative to a second waveguide. The first positive line is on a proximal side of the first waveguide relative to the second waveguide. The second differential line pair has a second negative line and a second positive line arranged on opposing sides of the second waveguide. The second negative line is on a distal side of the second waveguide relative to the first waveguide. The second positive line is on a proximal side of the second waveguide relative to the first waveguide. The first and second waveguides each include lithium niobate and / or lithium tantalate.

Techniques for joining dissimilar materials in microelectronics are provided. Example techniques direct-bond dissimilar materials at an ambient room temperature, using a thin oxide, carbide, nitride, carbonitride, or oxynitride intermediary with a thickness between 100-1000 nanometers. The intermediary may comprise silicon. The dissimilar materials may have significantly different coefficients of thermal expansion (CTEs) and / or significantly different crystal-lattice unit cell geometries or dimensions, conventionally resulting in too much strain to make direct-bonding feasible. A curing period at ambient room temperature after the direct bonding of dissimilar materials allows direct bonds to strengthen by over 200%. A relatively low temperature anneal applied slowly at a rate of 1° C. temperature increase per minute, or less, further strengthens and consolidates the direct bonds. The example techniques can direct-bond lithium tantalate LiTaO3 to various conventional substrates in a process for making various novel optical and acoustic devices.

An acoustic wave device includes a support substrate, a multilayer body, and an IDT electrode. The multilayer body includes a lithium tantalate piezoelectric layer and a lithium niobate piezoelectric layer that are laminated, and is on the support substrate. The IDT electrode is on the multilayer body, and includes electrode fingers. When a wavelength of an acoustic wave determined by a pitch of the electrode fingers is denoted as λ, a thickness of the multilayer body is about 0.66λ or less.

The invention discloses a lithium tantalate wafer with high electrical conductivity and a preparation method thereof, belonging to the technical field of crystal materials. The invention comprises the following steps: uniformly mixing an organic carbon source, an inorganic carbon source and spherical zinc powder to obtain a reducing agent; embedding the reducing agent on the surface of the lithium tantalate wafer, placing the wafer in a heat treatment furnace, introducing an inert gas for carbonization; introducing a reducing gas for heat treatment, taking the wafer out, and obtaining the lithium tantalate wafer with high electrical conductivity; the organic carbon source comprises at least one of sucrose and phenolic resin; the inorganic carbon source comprises at least one of flaky graphite and graphene; the invention uses an organic carbon source, an inorganic carbon source and spherical zinc powder in a mass ratio of 1: (0.3-0.6): (0.4-0.7) as a reducing agent, embeds the reducing agent on the surface of the lithium tantalate wafer, firstly undergoes carbonization, and then undergoes heat treatment, so as to effectively improve the electrical conductivity of the lithium tantalate wafer and has broad application prospects.

The invention provides a method and equipment for thinning a lithium tantalate bonded wafer, and relates to the technical field of wafer thinning, initial surface type data is detected firstly, then the inclination angle of a coarse grinding wheel is adjusted according to the positive and negative values of the initial BOW value of the initial surface type data, and then the wafer is subjected to coarse thinning. And then the rough grinding surface type data of the thinned wafer are detected again, the inclination angle of the fine grinding wheel is adjusted according to the positive and negative values of the rough grinding BOW value of the rough grinding surface type data, and then fine thinning is conducted on the wafer. Compared with the prior art, the wafer is thinned through rough thinning and fine thinning, the inclination angle of the grinding wheel can be adjusted according to the BOW value before the thinning action, the grinding wheel can be better matched with the wafer in the thinning process, on one hand, the risk of brittle fracture such as edge breakage can be reduced, a subsurface damage layer can be slowed down, and therefore the service life of the grinding wheel is prolonged; and on the other hand, the wafer can be adaptively corrected, and the problem of serious warping caused by thinning is solved. And the quality of the thinned ultrathin lithium tantalate bonded wafer can be effectively improved.

The invention provides an elastic wave device, a circuit and an electronic apparatus. The elastic wave device includes an electrode and two piezoelectric layers. The two piezoelectric layers may be referred to as a first piezoelectric layer and a second piezoelectric layer, respectively. The electrode is arranged on the first piezoelectric layer, and the first piezoelectric layer is arranged on the first piezoelectric layer. The electrode is configured to generate an elastic wave having a wavelength [lambda]. The Euler angle of the first piezoelectric layer is different from the Euler angle of the second piezoelectric layer. The first piezoelectric layer and the second piezoelectric layer are made of the same material, and the first piezoelectric layer and the second piezoelectric layer are made of lithium tantalate or lithium niobate. The two piezoelectric layers with different Euler angles can suppress or reduce unnecessary high-order mode response, so that the main vibration mode of the elastic wave device has good electrical characteristics.

A lithium tantalate reducing agent and blackening process containing nanomaterials, belonging to the technical field of crystal materials, comprises the following raw materials in weight percentage: FeSiAl micron sheets, carbon nanospheres and Fe-C core-shell nanoparticles are uniformly mixed in a mass ratio of 90:5:5, and stirred by an electric stirrer. The present invention can realize a simple and controllable blackening process of lithium tantalate, and at the same time, by controlling the temperature of the central temperature zone, ensure the effect of different blackening temperatures, and realize the regulation of yellow light transmittance and resistivity of lithium tantalate wafers.

An acoustic resonator includes a substrate, a lithium tantalate layer disposed over the substrate, and a transducer on the lithium tantalate layer. The lithium tantalate layer has a crystalline orientation defined by a first Euler angle (λ), a second Euler angle (μ), and a third Euler angle (θ), and the first Euler angle (λ), the second Euler angle (μ), and the third Euler angle (θ) are chosen such that an acoustic plate mode (APM) is a dominant mode excited in the acoustic resonator.

The invention discloses a high-stability piezoelectric nano material for a lithium tantalate wafer and a preparation method of the high-stability piezoelectric nano material, and belongs to the technical field of modified nano materials. The nano material is prepared by taking a lithium tantalate nano matrix as a core and combining a rare earth doping agent, silicon carbide nano fibers, graphene quantum dots, a SiO2-Al2O3 ceramic layer and an organic silicon modifier through a multi-layer structure design and a fine process. The preparation method comprises the steps of core layer synthesis, middle layer preparation, outer layer coating and stepped sintering, and the uniformity and stability of the material structure are ensured. The innovation points are that rare earth doping optimizes the lattice structure and improves the piezoelectric property; the mechanical strength and the electrical conductivity are enhanced through nanometer compounding; and the ceramic layer provides high-temperature-resistant and corrosion-resistant protection. The obtained material shows excellent piezoelectric property and structural stability in extreme environments such as high temperature, moisture and corrosion, and is suitable for high-performance application of lithium tantalate wafers in the fields of aerospace, deep sea exploration and the like.

The invention discloses a neuromorphic transistor taking lithium niobate or lithium tantalate single crystal as a gate medium and a preparation method of the neuromorphic transistor, and belongs to the technical field of semiconductor devices. The neuromorphic transistor comprises a substrate layer, a bottom gate electrode layer, a gate dielectric layer and a patterned electrode assembly which are arranged from top to bottom. The material of the substrate layer comprises single crystal LiNbO3 (0001) or single crystal LiTaO3 (0001); the bottom gate electrode layer comprises a single crystal ZnSnO3 thin film; and the gate dielectric layer comprises a single crystal LiNbO3 film or a single crystal LiTaO3 film. A gate dielectric layer can be directly deposited after a single crystal ZnSnO3 thin film is epitaxially grown on the single crystal LiNbO3 (0001) or single crystal LiTaO3 (0001) substrate, the situation of lattice mismatch is effectively avoided, meanwhile, introduction of a buffer layer is reduced, thin film growing methods in a device structure are physical vapor deposition methods, safety is higher, and process cost is lower.

An acoustic wave device includes a high acoustic velocity material layer, a piezoelectric layer including lithium tantalate, and an IDT on the piezoelectric layer and including electrode finger portions each including at least one electrode finger portion layer. An acoustic velocity of a bulk wave propagating in the high acoustic velocity material layer is higher than that in the piezoelectric layer. TR=(1 / 3.15)× (Tm / TIDT)×100 [%] is satisfied, where TR is a value obtained by dividing a thickness ratio of an Al-equivalent normalized thickness Tm of a mass addition film relative to an Al-equivalent normalized thickness TIDT of the electrode finger portion by about 3.15. A wavelength ratio width and a thickness ratio have values within a range on an ellipse and inside of the ellipse on an xy plane expressed by:x=0.19×cos(−5.5°)×cos θ−0.021×sin(−5.5°)×sin θ+0.0146×TIDT2−0.229×TIDT+1.5611+0.4×(d−0.55),andy=0.19×sin(−5.5°)×cos θ+0.021×cos(−5.5°)×sin θ+10.15.

The invention relates to the field of semiconductors and piezoelectric materials, in particular to a method for improving bonding strength of a lithium tantalate wafer, which comprises the following steps: a) thinning, polishing and cleaning the lithium tantalate wafer; b) cleaning the substrate slice with a weakly alkaline solution and then immediately cleaning the substrate slice with a cooling water bath; c) carrying out step-by-step cooling treatment on the substrate slice and then storing at constant temperature; d) carrying out surface activation on the lithium tantalate wafer and the substrate slice by using plasma; e) aligning the lithium tantalate wafer and the substrate slice, and pressurizing and bonding to obtain a bonded slice; and f) inspecting the bonding sheet. By optimizing the lithium tantalate wafer thinning and polishing process and the substrate slice low-temperature treatment process, the problems of edge tilting and surface roughness of the lithium tantalate wafer, self defects of the substrate slice and poor bonding caused by difference of thermal expansion coefficients of a functional layer and a substrate layer during bonding are effectively solved, and high-strength, high-precision and high-stability bonding is realized.

The present invention provides a high-toughness thermoformed natural stone basin and a preparation method thereof, which includes taking an active composition, modified kaolin, modified bentonite, modified additives, alcohol ether carboxylate sodium, titanate coupling agent, isopropanol, artemisia sphaerocephala Krasch gum, aluminum silicate, lithium tantalate and calcium copper titanate, and through processes such as mixing, ultrasonic treatment, refrigeration treatment, preforming pressing, gradient roasting, demolding, etc., a natural stone basin with good strength, toughness, and acid and alkali resistance is obtained.

This application discloses a method and device for fabricating a periodically polarized ultrathin lithium niobate / lithium tantalate device, belonging to the field of nonlinear optical device manufacturing. The method includes: fabricating and polarizing periodic electrodes on a provided ferroelectric crystal wafer to form a periodically polarized master wafer; bonding the master wafer to a carrier substrate using optical resin-assisted bonding or direct bonding to form a composite structure; thinning and polishing the side of the master wafer away from the carrier substrate to obtain an ultrathin periodically polarized crystal functional layer; and fabricating the structure of the ultrathin periodically polarized crystal functional layer to obtain a periodically polarized ultrathin lithium niobate / lithium tantalate device. This method avoids the inherent problems of high-voltage breakdown and poor domain quality in existing technologies when directly polarizing ultrathin crystals by placing the high-risk polarization step on a thick, stable wafer.

The application discloses a heat treatment device for high-concentration magnesium-doped lithium tantalate single crystal growth, and relates to the field of high-concentration magnesium-doped lithium tantalate single crystal growth. The heat treatment device comprises a base, a tank body is arranged at the bottom of the base, a quartz crucible is arranged in the tank body, a circular ring plate is arranged at the top of the quartz crucible, a sliding groove is arranged on the inner wall of the circular ring plate, a wedge-shaped block is arranged in the sliding groove, a ring-shaped block plate is arranged at the tail end of the wedge-shaped block, a second threaded ring is fixed to the top inside the circular ring plate, the second gear drives the first threaded ring to rotate, the first threaded ring drives the second threaded ring to move downwards, the second threaded ring drives the circular ring plate to move downwards, the bottom of the circular ring plate extrudes the liquid after high-temperature dissolution in the quartz crucible, and the steam pocket in the liquid is extruded out.

To provide a composite wafer in which an LT film or an LN film having a high thermal expansion coefficient is laminated on a support substrate having a low thermal expansion coefficient, and which can reduce spurious caused by reflection of an incident signal on a bonding interface between the LT film or the like and the support substrate, and to provide a method of manufacturing the same.SOLUTION: A method for producing a composite wafer according to an embodiment of the present invention includes a step of performing ion implantation into a single crystal wafer serving as a support substrate, a step of performing surface activation treatment on one or both of a piezoelectric wafer of lithium tantalate or lithium niobate and the single crystal support substrate, and a step of thinning the piezoelectric wafer after bonding.SELECTED DRAWING: Figure 5

The application relates to the technical field of battery diaphragm, and discloses a lithium ion battery diaphragm with high viscosity and high safety, which is prepared from the following components in parts by weight: 15-20 parts of polyolefin, 80-85 parts of pore-forming agent and 2-4 parts of filler; the viscosity average molecular weight of the polyolefin is 1-4 million; the raw material of the filler comprises component A and component B in a mass ratio of 1:19-19:1; the component A comprises barium stearate; and the component B comprises one or more of lithium molybdate, lithium tungstate and lithium tantalate. Through the technical scheme, the problem of low strength of the lithium battery diaphragm in the related art is solved.

The present application belongs to the field of wafer processing, in particular to a lithium tantalate wafer blackening process. The lithium tantalate wafer is supported by the support block at the lower part of the heat treatment box, and the lower part of the lithium tantalate wafer is clamped by the clamping block. The lower part of the wafer is clamped and heated for a certain period of time by the clamping block at the lower part of the heat treatment box. Then, the clamping block at the upper part of the heat treatment box moves to the upper part of the wafer and clamps the upper part of the wafer. The wafer is heated again. The lower part of the lithium tantalate wafer is clamped and heat treated for a certain period of time by the clamping block at the lower part of the heat treatment box. Then, the upper part of the lithium carbonate wafer is clamped and heat treated for a certain period of time by the clamping block at the upper part of the heat treatment box. To some extent, the clamping surface is prevented from being blocked by the clamp, so that the clamping end surface cannot be fully heated, and the blackening effect of the clamping end surface is affected.

The invention belongs to the technical field of semiconductors, and particularly relates to a lithium niobate / lithium tantalate thin film doped with active ions and a preparation method of the lithium niobate / lithium tantalate thin film. The thin film comprises a substrate, an isolation layer, a passive thin film layer and an active thin film layer which are stacked from bottom to top, wherein the passive thin film layer and the active thin film layer are respectively made of lithium niobate and lithium niobate doped with active ions, or lithium tantalate and lithium tantalate doped with active ions. Through the specific layer structure design, the lithium niobate / lithium tantalate passive and active photonic device monolithic integrated thin film which is low in loss and reliable in bonding is obtained.

Provided in the present application are an elastic wave device, a circuit and an electronic apparatus. The elastic wave device comprises an electrode and two piezoelectric layers, wherein the two piezoelectric layers may be respectively referred to as a first piezoelectric layer and a second piezoelectric layer; the electrode is provided on the first piezoelectric layer, and the first piezoelectric layer is provided on the second piezoelectric layer; and the electrode is configured to generate an elastic wave having a wavelength λ. The Euler angle of the first piezoelectric layer is different from that of the second piezoelectric layer; and the material of the first piezoelectric layer is the same as that of the second piezoelectric layer, and the first piezoelectric layer and the second piezoelectric layer are made of lithium tantalate or lithium niobate. The two piezoelectric layers having different Euler angles can suppress or reduce unnecessary high-order modal responses, such that the primary vibration mode of the elastic wave device has good electrical characteristics.

The utility model relates to an end effector of a lithium tantalate single crystal rod transplanting robot, which comprises a driving air cylinder, a first clamping piece, a second clamping piece, a first sliding block, a second sliding block and a sliding rail, the sliding rail is fixedly arranged on the driving air cylinder, the first sliding block and the second sliding block are connected to the sliding rail in a sliding mode, and the first clamping piece and the second clamping piece are fixedly arranged on the driving air cylinder. The driving air cylinder is connected with the first sliding block and the second sliding block, so that the driving air cylinder drives the first sliding block and the second sliding block to move on the sliding rail; the first clamping piece and the first sliding block are fixedly installed together, and the second clamping piece and the second sliding block are fixedly installed together, so that the driving air cylinder drives the first clamping piece and the second clamping piece to be close to each other or away from each other. When the first clamping piece and the second clamping piece are close to each other, the first clamping piece and the second clamping piece are used for clamping a lithium tantalate single crystal rod.

A SAW resonator with reduced spurious modes is provided. The resonator comprises a (111) silicon carrier substrate (CS), an electrode structure (ES) and a piezoelectric layer (PIL). The carrier substrate has a crystal orientation with the Euler angles (−45°±10°; −54°±10°; 60°±30°) and the piezoelectric layer comprises LiTaO3 and has a crystal orientation with the Euler angles (0°; 56°±8°; 0°). There may be intermediate layers (IL1, IL2) of SiO2 and amorphous or polycrystalline materials. In addition a silicon nitride layer is provided as passivation (PAL). Electrodes are made of aluminum. Thicknesses of all layers are selected in particular ranges to optimize SAW behaviour.

The present invention relates to a monolithic integrated high-speed modulation silicon-based optical chip and a preparation method thereof, which comprises, from bottom to top, a silicon-based optoelectronic layer (I), an intermediate layer (II), a lithium niobate layer or a lithium tantalate layer (III); the silicon-based optoelectronic layer (I) comprises, from bottom to top, a substrate (1), an insulating layer (2), a silicon waveguide (3), an InP laser (4), a silicon germanium photodetector (5), and a thermo-optical phase shifter (6). Based on the excellent electro-optical modulation performance of lithium niobate (or lithium tantalate), the present invention focuses on a special bonding method and a CMOS-compatible silicon photonic flow-through process, obtains a lithium niobate (or lithium tantalate)-silicon multilayer structure, and further realizes a fully integrated transceiver optical chip with a laser, a photodetector, and an electro-optical modulator, which can meet the current requirements of on-chip optical systems for high compactness and low power consumption.