89 results about "Lithium niobate" patented technology

This invention belongs to the field of wavelength division multiplexing optical communication technology, specifically relating to a reverse coupler based on a thin-film lithium niobate platform. The reverse coupler includes: a lithium niobate-on-insulator substrate, a first waveguide, a second waveguide, and a coupling region. The first and second waveguides are disposed in the device layer of the lithium niobate-on-insulator substrate. The first and second waveguides are arranged in parallel along the light propagation direction within the coupling region. A periodic grating perturbation structure is disposed on the first and / or second waveguides. This reverse coupler utilizes the grating perturbation structure to ensure that the modes of the two waveguides satisfy the phase matching condition. The optical signal input to one waveguide is reverse-coupled to the falling port of the other waveguide. Utilizing the large photoelectric coefficient of lithium niobate material, this reverse coupler can tune its spectrum under specific conditions by applying a voltage.

This application provides a silicon photonics thin-film lithium niobate hybrid integrated optoelectronic chip, its fabrication method, and a system, relating to the field of optoelectronics technology. Based on a thin-film lithium niobate platform, multiple thin-film lithium niobate modulators are fabricated on a thin-film lithium niobate wafer, and qualified thin-film lithium niobate modulator chips are selected. Based on a silicon photonics process platform, optoelectronic device structures other than the modulators are fabricated on a silicon photonics wafer, and a wafer map is generated to identify the locations of qualified chips. A transition structure with dimensions matching the silicon photonics wafer is then provided. The silicon photonics wafer and the transition structure are assembled to form a composite wafer. Based on the wafer map, qualified thin-film lithium niobate modulator chips are transferred and mounted one by one onto the composite wafer, and optical and electrical connections are completed. Finally, the mounted composite wafer is sliced ​​and tested to obtain the silicon photonics thin-film lithium niobate hybrid integrated optoelectronic chip. The solution provided in this application has the advantages of good process compatibility, high yield, and low cost.

A light guide member of a waveguide structure of an image display device for guiding image light incident from a display and emitting the image light toward an eye of a user, characterized by being formed of a single crystal composed of lithium niobate. According to the present invention, a light guide member having a high refractive index and a high internal transmittance can be provided.

This application discloses a sensor assembly, including an insulating substrate comprising a first surface and a second surface disposed opposite to each other; a surface acoustic wave (SAW) pressure sensor disposed on the first surface, the SAW pressure sensor comprising a piezoelectric lithium niobate layer and two pairs of interdigital transducers disposed on the surface of the piezoelectric lithium niobate layer, the piezoelectric lithium niobate layer having a cavity and a corresponding thinned sensitive membrane region, the two pairs of interdigital transducers being disposed around the thinned sensitive membrane region in mutually perpendicular directions; and a platinum resistance temperature sensor and an interdigital capacitance humidity sensor disposed on the second surface. By having the SAW pressure sensor, platinum resistance temperature sensor, and interdigital capacitance humidity sensor disposed opposite to each other on the insulating substrate, combined with the cavity formed on the piezoelectric lithium niobate layer, and the two pairs of interdigital transducers disposed in mutually perpendicular directions, the detection accuracy is improved and crosstalk is reduced.

A photonics device package is described. The photonics device package includes a thin film lithium-containing (TFLC) photonics integrated circuit (PIC) and an additional integrated circuit (IC). The TFLC PIC includes TFLC optical structures and electrodes. The TFLC structures include at least one TFLC electro-optic material. At least one of the TFLC structures includes a ridge and a slab and has a width not exceeding one micrometer. The TFLC PIC has a footprint. The TFLC structures occupy not more than fifty percent of the footprint. In addition, the TFLC structures are encapsulated in the TFLC PIC. The additional IC is mechanically coupled with the TFLC PIC after formation of the TFLC structures.

The application discloses a method for realizing optical wave and terahertz near-zero refractive index based on a nonlinear mixed waveguide, and steps are as follows: thin film lithium niobate is selected as a nonlinear material to process a mixed waveguide; a one-dimensional corrugated waveguide is used on the mixed waveguide to show a Dirac point-like dispersion characteristic at a Gamma point; an average nonlinear coupling coefficient of the mixed waveguide is calculated, and the quality factor of the zero-refractive-index waveguide is optimized by adjusting the thickness and period of the thin film lithium niobate; hollow rectangular metal waveguides are arranged around the thin film lithium niobate waveguide, and are used for guiding the propagation of terahertz waves and enhancing the nonlinear interaction in the difference frequency process; and the near-zero refractive index of various terahertz frequencies is realized by changing the width of the hollow rectangular metal waveguide. By jointly designing the nonlinear mixed waveguide of the terahertz and optical wave near-zero refractive index, the problems of phase mismatch and weak nonlinear interaction of the conversion of the optical wave to the terahertz wave are solved, so that the efficient conversion of the optical wave to the terahertz wave across the wave band is realized through on-chip optical difference frequency.

This invention provides a method and system for spectral inversion calculation of chirped gratings in lithium niobate thin films. The method includes: sequentially performing time-frequency domain transformation, window truncation, and time-shifting on a preset ideal target response of the grating to obtain a physically realizable target response; using the physically realizable target response as the initial complex reflection response, performing layer-by-layer recursive calculation on the grating using a layer-by-layer peeling algorithm to obtain the complex coupling coefficients corresponding to each layer of the grating, and extracting the coupling coefficient distribution and phase distribution of the grating; obtaining the structural parameters of the chirped Bragg grating based on the coupling coefficient distribution and phase distribution; constructing a physical model of the grating based on the structural parameters, and performing simulation calculations on the physical model to obtain the spectral response. This invention, based on the traditional grating design process, introduces a layer-by-layer peeling algorithm for inversion calculation of the grating structure, inversely obtaining the coupling coefficients and phase distribution of the grating, as well as the corresponding grating structural parameters, and constructing a corresponding physical model, exhibiting strong target-oriented characteristics.

The application discloses a high-polarization-extinction-ratio integrated Y waveguide structure based on a thin film lithium niobate, relates to the fields of microwave photonics, integrated optoelectronics and high-precision inertial sensing technology, and comprises a substrate, a lower cladding layer, a thin film lithium niobate layer and an upper cladding layer from bottom to top; and the polarization extinction ratio of the device is significantly improved according to the application; in view of the problem of poor polarization extinction ratio performance of the current monolithic integrated thin film lithium niobate Y waveguide due to the lack of an on-chip efficient polarization structure, the application creatively utilizes mode parity symmetry for filtering; the energy zero point position of the TE1 mode is determined by the waveguide electromagnetic field eigen equation and does not drift with the external environment temperature or stress; unlike the directional coupler relying on nanoscale gaps or the subwavelength grating with a minimum line width; the end-to-end transmission loss of the polarization and filtering of the application can be controlled at a very low level, so that the optical power margin and the overall signal-to-noise ratio of the fiber-optic gyroscope system detection end are significantly improved.

This invention relates to a lithium niobate electro-optic modulator, its fabrication method, and its application. The lithium niobate electro-optic modulator, from bottom to top, comprises a ground electrode, a substrate layer, a buried oxide layer, a lithium niobate waveguide, and a high-dielectric-constant cladding. Symmetrically distributed optical isolation trenches are arranged on both sides of the lithium niobate waveguide. The high-dielectric-constant cladding includes a first cladding and a second cladding from the inside out, wherein the dielectric constant of the first cladding is less than that of the second cladding. The number of high-dielectric-constant cladding layers is ≥2. The lithium niobate electro-optic modulator also includes a signal electrode embedded within the high-dielectric-constant cladding and located above the optical isolation trenches. The synergistic effect of the optical isolation trenches and the high-dielectric-constant cladding in this invention enables the lithium niobate electro-optic modulator to possess not only high modulation efficiency but also high bandwidth. Furthermore, the lithium niobate electro-optic modulator of this invention exhibits excellent power tolerance.

This application discloses a fabrication process for simultaneously obtaining an ultrathin lithium niobate piezoelectric single crystal wafer and a heterogeneous thin-film bonding substrate, belonging to the field of semiconductor wafer fabrication technology. The process includes the following steps: (1) ion implantation of a rotated tangential lithium niobate wafer, with the ion implantation dose gradually increasing from the center of the wafer outwards; pre-annealing of the substrate wafer; (2) activation and bonding of the ion implantation surface of the lithium niobate wafer obtained in step (1) to the substrate wafer to obtain a bond; (3) a two-step thinning process to reduce the thickness of the lithium niobate wafer to 40-200 μm; (4) annealing of the bond after thinning in step (3) to obtain an ultrathin lithium niobate piezoelectric single crystal wafer and a heterogeneous thin-film bonding substrate. This process, by processing the substrate wafer and the lithium niobate wafer, can simultaneously obtain a non-destructive ultrathin lithium niobate piezoelectric single crystal wafer and a heterogeneous thin-film bonding substrate, meeting the current demand for ultrathin lithium niobate piezoelectric single crystal wafers.

We utilize high-quality-factor (high-Q) metasurfaces patterned either in or adjacent to electro-optical or thermo-optical materials such as lithium niobate, barium titanate, or thermally-sensitive polymers. The metasurface includes nanoantennas that act as dipole emitters; the particular structure and arrangement of nanoantennas can steer light to particular directions or focus light, The electromagnetic metasurface supports one or more guided mode resonances. The metasurface also includes a perturbation superposed on the metasurface features and configured to couple free-space radiation to the guided mode resonances.

The embodiment of the present disclosure provides an on-chip integrated structure, comprising: a substrate; a waveguide layer located above the substrate, the waveguide layer having a silicon waveguide, a transition waveguide and a lithium niobate waveguide extending along a first direction; the first direction is parallel to the surface of the substrate; the silicon waveguide, the transition waveguide and the lithium niobate waveguide are sequentially stacked in the direction away from the surface of the substrate; the transition waveguide has a first part and a second part arranged in the first direction in sequence; the projection of the first part on the substrate at least partially coincides with the projection of the silicon waveguide on the substrate; the projection of the second part on the substrate at least partially coincides with the projection of the lithium niobate waveguide on the substrate.

This invention discloses a thin-film lithium niobate silicon optical integrated chip and its fabrication method. The thin-film lithium niobate silicon optical integrated chip sequentially comprises a metal-free silicon photonic base chip, a thin-film lithium niobate waveguide layer bonded thereon, a silicon dioxide cladding covering the chip, and at least two functionally separated metal layers located above the cladding. The first metal layer serves as an electrical contact and modulation electrode, and the second metal layer is interconnected with the first layer via a visor and serves as a traveling wave electrode. The fabrication method is used to fabricate the thin-film lithium niobate silicon optical integrated chip. Advantages: In this invention, the silicon photonic base chip does not contain any metallization layer (except for metal silicides) before bonding to the thin-film lithium niobate layer, thus ensuring the flatness of the bonding interface and bonding quality, and reducing interlayer coupling loss.

The application discloses a sodium ion conductivity detection system and method based on a taiji-shaped lithium niobate waveguide. The system comprises a lithium niobate film, a taiji-shaped Mach-Zehnder interference waveguide formed on the lithium niobate film, the taiji-shaped Mach-Zehnder interference waveguide comprising an MMI-type beam splitter, a reference arm and a sensing arm symmetrically curved in a taiji shape and an MMI-type beam combiner, and metal electrodes arranged on the sides of the reference arm and the sensing arm respectively. When a sodium ion solution is introduced into a sensing area, the change of the sodium ion solution conductivity changes the local electric field distribution at the electrode-liquid interface, thereby changing the effective modulation voltage of the waveguide of the sensing arm and changing the refractive index of the waveguide of the sensing arm through the Pockels effect to output an interference light intensity change signal, and then the sodium ion solution conductivity to be detected is detected. The application changes the local electric field at the spiral electrode interface and modulates the refractive index of the waveguide by the change of the sodium ion solution conductivity, realizes the output of the interference light intensity change signal, and detects the sodium ion solution conductivity to be detected.

The application belongs to the technical field of integrated optical devices, and discloses an amorphous silicon-thick film lithium niobate hybrid integrated bending converter and a preparation method thereof. The thick film lithium niobate layer of the device is photoetched to form a thick film lithium niobate end face coupler, a first thick film lithium niobate waveguide and a second thick film lithium niobate waveguide. The amorphous silicon layer comprises a first and a second amorphous silicon-lithium niobate wedge waveguide optical mode conversion structure and an amorphous silicon bending waveguide. The optical signal transmitted in the first thick film lithium niobate waveguide can be transmitted to the amorphous silicon bending waveguide and finally transmitted to the second thick film lithium niobate waveguide, so that the bending conversion output is realized. The amorphous silicon functional component is introduced between the two thick film lithium niobate waveguides, so that the problems of weak optical binding capacity of the thick film lithium niobate bending waveguide and large bending radius of the waveguide are effectively solved.

The embodiment of the present disclosure provides a lithium niobate optical transceiver and a forming method thereof, wherein the lithium niobate optical transceiver comprises a lithium niobate modulator chip, and a detector chip, a laser chip, an electric driving chip and a transimpedance amplifier chip which are inversely stacked on the lithium niobate modulator chip; wherein: the electric driving chip is used for providing a modulation driving voltage to a modulation electrode in the lithium niobate modulator chip, so that the lithium niobate modulator modulates an optical signal generated by the laser chip; the detector chip is used for detecting the modulated optical signal and converting the modulated optical signal into an electric signal; and the transimpedance amplifier chip is used for amplifying the electric signal.

The application belongs to the technical field of electrical sensors, and particularly relates to a preparation method of a surface acoustic wave sensor for improving the binding force of a gate electrode, comprising the following steps: cleaning a lithium niobate substrate, drying the lithium niobate substrate to obtain a pretreated lithium niobate substrate; spin-coating 3510T photoresist on the pretreated lithium niobate substrate, and then performing a pre-baking treatment at 100-120 DEG C; performing photoetching on the photoresist of the substrate after the pre-baking treatment, and then performing exposure and development treatment; performing post-baking treatment on the substrate after the development treatment at 120-140 DEG C; spin-coating photoresist on one side of the substrate after the post-baking treatment, and magnetron sputtering a platinum-gold layer; slowly heating the substrate after the magnetron sputtering treatment to 450-500 DEG C to perform heat treatment; removing the photoresist in the substrate after the heat treatment to form a platinum-gold gate electrode, and obtaining the surface acoustic wave sensor. The application reduces the cost and improves the stability of electrode material adhesion, and has a wide application prospect.

The application relates to a hetero-integrated gyro chip and a preparation method thereof, wherein a waveguide pattern of the gyro chip is prepared based on silicon nitride and thin film lithium niobate, and the waveguide pattern comprises an end face coupler, a polarizer, two 1x2 MMIs of a 3 dB beam splitter, an interlayer coupler, a Mach-Zehnder type thin film lithium niobate waveguide structure and ground-signal-ground electrodes, and an ultrathin silicon nitride waveguide ring; the Mach-Zehnder type thin film lithium niobate waveguide structure comprises two phase modulators; the phase modulators are driven in a push-pull mode and are coupled in and out of the ultrathin silicon nitride waveguide ring in clockwise and counterclockwise modes; the gyro chip comprises an on-chip SLD light source and an on-chip detector which are integrated on the edge of the waveguide structure through end face packaging. The gyro chip is prepared based on a hetero-integration scheme of thin film lithium niobate and silicon nitride, the integration degree is greatly improved, the area and volume of traditional components are reduced, wafer-level preparation with low cost can be realized, and the gyro chip has the characteristics of full integration and compactness.

This application discloses a lithium niobate single-crystal piezoelectric composite material, a high-frequency ultrasonic transducer, and its fabrication method, belonging to the technical field of piezoelectric ultrasonic transducers. The composite material uses lithium niobate single crystals as the functional phase and a polymer as the matrix phase, composited through a 1-3 or 2-2 type spatial structure, with a thickness of 5-300 μm and a lithium niobate volume fraction of 40%-70%, effectively reducing the material's acoustic impedance. The high-frequency ultrasonic transducer uses the above-mentioned composite material as the piezoelectric layer, combined with a matching layer and a backing layer, significantly improving ultrasonic transmission efficiency and imaging resolution. This application also provides a corresponding fabrication method, achieving mass production of high-performance transducers through femtosecond laser etching, bonding thinning, and other processes.

Acoustic resonator device, including: a substrate with a surface; a lithium niobate plate with a front and a back surface, the back surface being attached to the surface of the substrate, except for a region of the lithium niobate plate that forms a membrane spanning a cavity in the substrate; and an interdigital converter (IDT) on the front surface of the lithium niobate plate such that nested fingers of the IDT are arranged on the membrane, wherein the IDT and the lithium niobate plate are arranged such that a high-frequency signal applied to the IDT excites a primary acoustic shear mode within the membrane, wherein Euler angles of the lithium niobate plate are [0°, β, 0°], where β is greater than or equal to 60° and less than or equal to 70°.

Silicon-silicon oxide-lithium niobate high bandwidth electro-optical modulator and integrated method, the wafer is from bottom to top silicon substrate layer, silicon oxide isolation layer, lithium niobate film layer, silicon oxide buffer layer and silicon film layer; The electro-optical modulator comprises a multimode interferometer, a mode spot converter, an electro-optical phase shift arm, a traveling wave electrode and a thermoelectric electrode. The present application forms a conventional silicon waveguide, a thin silicon waveguide and a silicon oxide waveguide by etching multiple times, and forms a traveling wave electrode and a thermoelectric electrode by metal deposition. The silicon oxide layer acts as a buffer layer to alleviate the thermal mismatch and lattice mismatch between the silicon wafer and the lithium niobate wafer, improve the reliability and yield of the electro-optical modulator based on the silicon-silicon oxide-lithium niobate wafer, and provide a new degree of freedom for the design of the electro-optical modulator. The present application is compatible with CMOS process, and takes advantage of silicon, silicon oxide and lithium niobate, which is conducive to improving the compactness and reliability of integration.

The application discloses a lithium niobate on-chip reconfigurable diffraction computing system and method based on digital driving, and belongs to the technical field of optical computing. The system comprises a digital logic control module, a high-voltage digital interface module, a lithium niobate on-chip diffraction computing module and an optical input / output coupling module. The digital logic control module converts the binary logic level signal input from outside into a thermometer code control signal, which is directly converted into a binary switch driving signal through the high-voltage digital interface module, without the need for digital-to-analog conversion. The lithium niobate on-chip diffraction computing module comprises a diffraction pixel unit composed of a lithium niobate and a silicon dioxide composite waveguide. Each pixel unit is provided with equal-length sub-electrode segments segmented along the light propagation direction above the pixel unit. Discrete phase accumulation is realized through binary driving. The number of activated sub-electrode segments is proportional to the phase delay, full phase coverage in the range of 0-2pi is realized, and the modulated light wave completes diffraction computing through interference superposition.

This invention relates to the field of process control technology, specifically to an intelligent control system for thin-film lithium niobate etching processes based on machine learning. The system includes: a process sensing and acquisition module that collects thin-film lithium niobate etching process parameters, etching effect detection data, process environment data, and etching equipment status data in real time; a machine learning processing center that integrates and analyzes the data, using machine learning algorithms to uncover potential patterns, correlations, and anomalies; a process visualization and interactive platform that presents a real-time heatmap of etching parameter distribution, etching defect location, and etching effect trends, automatically switching interface layouts according to different process scenarios; an intelligent process decision engine that dynamically generates etching parameter adjustment strategies and process emergency response plans; and an etching parameter adjustment unit that adjusts the process parameters of the thin-film lithium niobate etching equipment and updates the control status. This solves the problems of poor adjustment response and low etching yield in existing technologies.

The application discloses an integrated Y waveguide modulator chip for a fiber-optic gyroscope, which comprises a substrate, a lower cladding layer and a waveguide core layer, the waveguide core layer is divided into a silicon nitride material core layer section and a lithium niobate thin film material core layer section, the silicon nitride material core layer section is configured as a 2*2 beam splitter chip, the lithium niobate thin film material core layer section is configured as a double-beam transmission waveguide chip, and modulation electrodes are arranged on the lithium niobate thin film material core layer section; the silicon nitride material core layer section and the lithium niobate thin film material core layer section are designed in a stepped mode and are connected through BCB material, so that efficient end face coupling connection is directly realized. In addition, the silicon-based PLC is combined with a proton exchange process on a micron film platform, the silicon-based PLC has high process maturity and stable performance; the proton exchange waveguide has natural polarization ability, high signal transmission efficiency and high quality, and the combination of the two can realize a stable high-performance chip structure, and the overall chip does not have a complex mode spot conversion structure.

The application discloses a device and method for cutting fluoranthene crystal by using a photo-induced electric field of lithium niobate. The method uses a spatial electric field generated by laser irradiation of iron-doped lithium niobate to realize cutting of micron-size fluoranthene crystal under heating conditions. The whole device is simple to build, and realizes real-time control of the crystal cutting position and residual length. The technology can be applied to various applications of organic field effect transistors and other organic optoelectronics, and has important significance for processing and modification of organic crystals.

The application discloses a hetero-integrated silicon-based thin film lithium niobate modulator, which comprises a Si device layer, a SiO2 cladding layer, a substrate Si, an LNOI layer and a transmission electrode Ti-Au; the SiO2 cladding layer is arranged on the Si device layer; the substrate Si is arranged on the Si device layer and in the SiO2 cladding layer; the LNOI layer is integrated with the SiO2 cladding layer in a bonding mode, and the LNOI layer is arranged on the SiO2 cladding layer; and the transmission electrode Ti-Au is arranged on the LNOI layer. The application further provides another hetero-integrated silicon-based thin film lithium niobate modulator. The application further provides a manufacturing method of the above-mentioned hetero-integrated silicon-based thin film lithium niobate modulator. The application can integrate LN materials, and the integration method is simple.

An acoustic wave device configured to generate a surface acoustic wave having a wavelength L is disclosed. The acoustic wave device can include a substrate, a piezoelectric layer that includes lithium niobate, an interdigital transducer electrode, an overcoat dielectric layer, and / or a raised frame structure. The piezoelectric layer is disposed at least partially between the substrate and the interdigital transducer electrode. The overcoat dielectric layer is positioned over the interdigital transducer electrode. The raised frame structure is positioned over the overcoat dielectric layer. The raised frame structure includes a material of the overcoat dielectric layer. The raised frame structure is positioned in an edge region within 0.25 L and 0.45 L from an edge of an active region where the surface acoustic wave is generated. The acoustic wave device can include a trap-rich layer over the substrate and an intervening dielectric layer over the trap-rich layer.

A material according to the present technology may include a silicon substrate, a single crystal oxide buffer layer formed on the silicon substrate, and a layer of lithium niobate formed on the single crystal oxide buffer layer. A method of producing a material according to the present technology may include the steps of forming a single crystal oxide buffer layer on a silicon substrate and forming a layer of lithium niobate on the single crystal oxide buffer layer.

The embodiment of the application provides a semiconductor structure and a preparation method thereof, and relates to the technical field of integrated photon devices. The semiconductor structure comprises a silicon substrate layer; a lithium niobate film layer formed on one side of the silicon substrate layer along a first direction; and a stress compensation layer formed between the silicon substrate layer and the lithium niobate film layer along the first direction, the stress compensation layer being used for partially or totally offsetting residual internal stress of the silicon substrate layer and the lithium niobate film layer. By introducing the stress compensation layer with preset initial internal stress between the silicon substrate layer and the lithium niobate film layer, the neutral axis position and the equivalent bending stiffness in the laminated structure are regulated, the equivalent bending moment in the annealing stage is offset, and then the residual internal stress of the obtained lithium niobate film-silicon substrate composite structure is reduced or eliminated, the warping of the lithium niobate film-silicon substrate composite structure is improved, the lattice distortion of the lithium niobate is improved, and thus the yield of the lithium niobate film-silicon substrate composite structure is improved.