179 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.

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 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.

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 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.

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 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.

The present invention provides a structure capable of suppressing parasitic waves that cannot be suppressed by controlling the surface shape of the bonding surface of the piezoelectric material substrate or the supporting substrate of the bonded body. The bonded body comprises: a supporting substrate; a piezoelectric material substrate formed of a material selected from the group consisting of lithium niobate, lithium tantalate, and lithium niobate-lithium tantalate; and a bonding layer that bonds the supporting substrate and the piezoelectric material substrate and contacts the main surface of the piezoelectric material substrate. At least one of the bonding surface of the supporting substrate and the bonding surface of the piezoelectric material substrate is measured using an X-ray reflectivity method. In this case, when the signal intensity during total reflection is set to 1, the relative intensity I of the reflected light from the bonding surface is 1.0×10 －4 Above 1.0×10 －1 In the following range, the approximation is performed by the following formula (1). [Formula 1] I = a(2θ) ‑b ·····(1)(θ is the incident angle to the bonding surface, a is 1.0×10 －5 Above 2.0×10 －3 Below, b is 5.0 or more and 9.0 or less).

An apparatus for a surface acoustic wave (SAW) device having an aluminum nitride substrate layer is disclosed. In one aspect, a SAW includes: a substrate layer comprising an aluminum nitride (AlN) substrate layer, an electrode structure including interdigitated transducers, and a piezoelectric layer disposed between the electrode structure and the substrate layer. In some aspects, the piezoelectric layer is lithium niobate or lithium tantalate.

The present invention relates to the technical field of tunable lasers, specifically providing a heterogeneously integrated tunable laser comprising a silicon nitride photonic chip and a lithium tantalate film bonded to the upper surface of the silicon nitride photonic chip. The lithium tantalate film and the silicon nitride waveguide layer are heterogeneously integrated to form a hybrid waveguide. The silicon nitride photonic chip is sequentially provided with a ring reflector, a gain chip, a vernier microring filter, a phase modulator, and a tunable ring mirror along the waveguide layer. The ring reflector and the tunable ring mirror form a resonant cavity. By adjusting the voltage applied to the electrodes of the vernier microring filter, the refractive index of the hybrid waveguide is changed, thereby achieving rapid switching of the output laser wavelength. By adjusting the voltage applied to the electrodes of the phase modulator, the refractive index of the hybrid waveguide is changed, thereby achieving linear frequency modulation signal output. The present invention overcomes the shortcomings of conventional tunable lasers, such as low tuning speed, narrow linear frequency modulation bandwidth, and small wavelength tunable range, while also simplifying the manufacturing process and achieving low economic cost.

The invention discloses a high-speed and high-extinction-ratio cascade MZI (Mach Zehnder Interferometer) electro-optical switch based on an electro-optical material. According to the electro-optical switch, a plurality of MZI structures are cascaded and integrated on an electro-optical material platform (such as lithium niobate or lithium tantalate) with an ultra-wide optical transparent window, and the initial phase error of each modulation arm is subjected to thermo-optical calibration by utilizing the refractive index change of an electro-optical material caused by temperature regulation and control; therefore, the consistency and long-term stability of the initial phase of the cascaded MZI are ensured. After thermo-optical phase calibration is completed, electro-optical refractive index regulation and control can be carried out on a plurality of phase modulation arms of the cascaded MZI at the same time only by applying a single driving voltage, and optical switch switching with the ultrahigh extinction ratio is achieved. The device has a pre-calibration function, a working point is stable and does not drift after calibration, and high-speed and high-extinction-ratio switching can be achieved only through a high-speed signal; and meanwhile, the device has the advantages of simple structure, flexible design, easiness in cascade expansion, low requirement on technological parameter tolerance and the like.

The invention relates to the technical field of semiconductors, and provides a method for preparing a silicon nitride film on the surface of a substrate. The method comprises the following steps: (1) in a first cavity in a nitrogen atmosphere, providing a hot plate with a process temperature, and preheating a substrate to a preheating temperature at a first interval; the substrate is made of lithium tantalate or lithium niobate; (2) placing the substrate with the preheating temperature on the surface of a hot plate, and heating the substrate to a process temperature; (3) depositing a silicon nitride film on the surface of the substrate with the process temperature; and (4) transferring the substrate on which the silicon nitride film is deposited into a second vacuum cavity for cooling. According to the method, the silicon nitride film is directly deposited on the surface of the lithium niobate or lithium tantalate substrate to obtain the silicon nitride film in a thermal radiation mode through combination of early-stage preheating and later-stage slow cooling under the condition that the lithium niobate or lithium tantalate substrate is complete. The method provided by the invention is simple in process and easy to implement, and has industrial application prospects.

The invention discloses a preparation method and application of a thin-film lithium niobate / lithium tantalate photoelectric device, and belongs to the technical field of manufacturing of photoelectric devices. The preparation method comprises the following steps: providing a wafer, wherein the material of the wafer is selected from lithium niobate and / or lithium tantalate; preparing at least one layer of silicon nitride optical waveguide structure on one surface of the wafer, wherein the silicon nitride optical waveguide structure is formed by a deposited silicon nitride film through micro-nano processing preparation; bonding one surface, with the silicon nitride optical waveguide structure, of the wafer on a planar substrate; and sequentially performing grinding thinning, ion modification and polishing on one surface, deviating from the silicon nitride optical waveguide structure, of the wafer to form a thin film wafer. According to the method, an efficient and high-quality processing mode is provided for manufacturing of related photoelectric devices, ferroelectric material etching and ion implantation processes are avoided, the performance of thin-film lithium niobate and lithium tantalate photoelectric devices can be effectively improved, and the method has the advantages of being simple in process, excellent in performance, economical in manufacturing and wide in application prospect.

The application discloses a cleaning method of lithium tantalate wafer, which comprises the following steps: soaking and cleaning the polished lithium tantalate wafer in an acid solution; performing ultrasonic cleaning in plasma-activated water; performing ultrasonic cleaning in an acid solution tank; and brushing the wafer on both sides. The application avoids wafer cracking caused by excessive thermal stress due to excessive temperature difference or excessively high temperature in the cleaning process through process improvement, improves the cleaning effect of the lithium tantalate wafer by setting ultrasonic plasma-activated water cleaning, using specific cleaning liquid and matching the use method of the cleaning liquid and ultrapure water, and ensures the surface cleanliness.

Provided is an acoustic resonator in a transverse excitation shear mode. The acoustic resonator comprises: an acoustic mirror (120), which comprises at least one first acoustic reflecting layer (121, 123, 125) and at least one second acoustic reflecting layer (122, 124), wherein the acoustic impedance of each first acoustic reflecting layer is less than that of each second acoustic reflecting layer; a piezoelectric layer (130), which is arranged on the acoustic mirror, and which comprises lithium niobate of a single crystal material and / or lithium tantalate of a single crystal material; electrode units (142, 143, 144), which are arranged on the piezoelectric layer (130) and are used for forming an electric field; and transverse reflectors (152, 154), which are arranged on the piezoelectric layer, are used for transversely reflecting acoustic waves, and can have a high electromechanical coupling coefficient and a high Q value at a frequency greater than 3 GHz.

The invention discloses a green synthesis method and application of a doped single crystal material based on a rapid Joule thermal method, and the green synthesis method comprises the following steps: S1, pretreating an initial single crystal to obtain a pretreated initial single crystal, the initial single crystal being selected from a lithium niobate single crystal or a lithium tantalate single crystal; s2, performing all-directional coating on the initial single crystal pretreated in the step S1 by using a metal foil to obtain the initial single crystal coated with the metal foil; and S3, placing the initial single crystal coated with the metal foil obtained in the step S2 on a clamp connected with a pulse power supply system, placing the clamp in a vacuum environment or an oxygen environment, applying current and voltage to the clamp through the pulse power supply system to enable the metal foil to generate Joule heat, keeping the temperature for a certain time, and cooling to prepare the metal-doped single crystal material. According to the technical scheme, the limitation of a traditional synthesis method in the aspects of energy consumption and doping uniformity is broken through, and high-efficiency and low-energy-consumption synthesis of the single crystal material with a controllable doping effect is realized.