A high-resolution transceiver integrated chip for robotic ultrasound localization

Abstract

The application relates to a high-resolution transceiving integrated chip for robot ultrasonic positioning, which comprises a piezoelectric transducer layer, from bottom to top, including a substrate, a bottom electrode layer, a piezoelectric film layer and a top electrode; and an optical sensing layer arranged on the top of the piezoelectric transducer layer, from bottom to top, including a waveguide lower cladding layer, a micro-ring waveguide, a bus waveguide and a waveguide upper cladding layer; the bus waveguide is coupled with the micro-ring waveguide; a cavity is hollowed out at the bottom of the substrate to form an acoustic cavity, and the position of the acoustic cavity corresponds to the position of the top electrode. The application heterogeneously integrates a chalcogenide micro-ring sensor on the basis of a piezoelectric micro-mechanical ultrasonic transducer, combines the emission ability and focusing ability of the piezoelectric micro-mechanical ultrasonic transducer to different frequency ultrasonic waves and the receiving ability of the micro-ring sensor to wide-spectrum ultrasonic waves, realizes the high-integration and high-resolution transceiving integrated chip, and provides a solution for real-time obstacle avoidance and accurate positioning of robots.

Description

Technical Field

[0001] This application relates to the field of integrated ultrasonic sensor chip technology, and more specifically, to a high-resolution transceiver integrated chip for ultrasonic positioning of robots. Background Technology

[0002] Robotic autonomous navigation and environmental perception rely on high-precision spatial positioning technology. Ultrasonic positioning, with its advantages of non-line-of-sight detection (penetrating smoke / dust), low power consumption, and controllable cost, has become an important supplement to lidar and visual sensing. Especially in scenarios such as indoor dynamic obstacle avoidance and mapping in confined spaces, ultrasonic chips can provide accurate real-time distance information. However, many robots today, such as assembly robots and automated guided vehicles, have increasingly higher requirements for ranging and positioning systems, posing greater challenges to ultrasonic positioning chips.

[0003] Traditional ultrasonic positioning solutions, such as discrete piezoelectric ceramic transducer systems, are bulky, susceptible to electromagnetic interference, consume a lot of power, and are incompatible with IC processes. Their receiving bandwidth is only 1-5MHz, resulting in low axial resolution. Furthermore, long reverberation times create detection blind zones exceeding 50cm, failing to meet the close-range obstacle avoidance requirements of robots. Piezoelectric micromechanical ultrasonic transducers (PMUTs) are ultrasonic transducers based on the piezoelectric effect. Their working principle utilizes the mechanical deformation of piezoelectric materials under an electric field to generate ultrasonic waves, while simultaneously receiving ultrasonic signals and converting them into electrical signals. They offer advantages such as miniaturization and integrability. During ultrasonic wave transmission, PMUT arrays can form phased arrays, with each unit independently emitting ultrasonic waves. By precisely controlling the phase delay of the emitted pulses from each unit, based on the Huygens-Fresnel principle, the spherical waves emitted by each unit interfere and synthesize in space, forming a sound beam with a specific direction and shape, thereby achieving a beam focusing effect. Phased array transducers (PMUTs) can focus ultrasound waves at a specific depth by controlling the transmission delay of each array element, reducing beam spread and thus improving axial resolution. However, similar to piezoelectric ceramics, when receiving ultrasound echo signals, problems such as electromagnetic interference, residual vibration interference, large dead zones, and insufficient receiving bandwidth result in low axial resolution, fundamentally limiting the ultrasound receiving performance of PMUTs. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing ultrasonic sensing and positioning chips, such as susceptibility to electromagnetic interference, residual vibration interference, large blind zone, and insufficient receiving bandwidth when receiving ultrasonic echo signals. This invention provides a high-resolution transceiver integrated chip for robot ultrasonic positioning, which effectively improves anti-interference capability and detection resolution.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A high-resolution transceiver integrated chip for ultrasonic positioning of robots is provided, comprising a piezoelectric transducer layer, which from bottom to top includes a substrate, a bottom electrode layer, a piezoelectric thin film layer, and a top electrode; and an optical sensing layer disposed on top of the piezoelectric transducer layer, which from bottom to top includes a waveguide lower cladding, a micro-ring waveguide, a bus waveguide, and a waveguide upper cladding; the bus waveguide is coupled to the micro-ring waveguide; a cavity is formed by hollowing out the bottom of the substrate to form an acoustic cavity, the position of which corresponds to the position of the top electrode.

[0006] This invention provides a high-resolution transceiver integrated chip for robot ultrasonic positioning. It heterogeneously integrates a chalcogenide microring sensor on the basis of a piezoelectric micromechanical ultrasonic transducer. It combines the transmission and focusing capabilities of the piezoelectric micromechanical ultrasonic transducer for ultrasonic waves of different frequencies with the receiving capability of the microring sensor for broadband ultrasonic waves, thus realizing a highly integrated, high-resolution transceiver integrated chip and providing a solution for real-time obstacle avoidance and precise positioning of robots.

[0007] Furthermore, the piezoelectric transducer layer includes N transducer units, which are arranged into an ultrasonic phased array according to a predetermined pattern. There are N top electrodes, which are arranged into a top electrode array according to a predetermined pattern. There are also N acoustic cavities; the positions of the N acoustic cavities correspond one-to-one with the positions of the N top electrodes. The N top electrode arrays are distributed such that each top electrode corresponds to a acoustic cavity on its bottom substrate. The acoustic cavity, substrate, bottom electrode layer, piezoelectric thin film layer, and top electrode constitute a transducer unit. The N transducer units arranged into an ultrasonic phased array according to a predetermined pattern can further improve the detection accuracy for nearby objects.

[0008] Furthermore, the optical sensing layer includes several micro-ring waveguides, which are arranged in a predetermined pattern to form a micro-ring sensing array. A bus waveguide connects these micro-ring waveguides in series, and each bus waveguide is coupled to one of the micro-ring waveguides. A laser beam is output from a signal light generator and transmitted via optical fiber to the bus waveguide. The bus waveguide connects the micro-ring waveguides in series. After receiving the ultrasonic echo signal generated by the object under test, the micro-ring sensor array converts it into an optical signal, which is then output from the bus waveguide. A photodetector converts the optical signal carrying ultrasonic information into an electrical signal, which is ultimately transmitted to an information receiving and processing device.

[0009] Furthermore, the transceiver integrated chip, from bottom to top, comprises: a substrate, a bottom electrode layer, a piezoelectric thin film layer, a top electrode array, a waveguide lower cladding, a micro-ring sensor array, a bus waveguide, and a waveguide upper cladding, forming a fully planar stacked structure. This invention employs a fully planar stacked structure: substrate - bottom electrode layer - piezoelectric thin film layer - top electrode array layer - waveguide lower cladding - micro-ring sensor array and bus waveguide layer - waveguide upper cladding; the piezoelectric transducer layer and optical sensing layer are vertically integrated using standard CMOS technology, eliminating the need for the complex alignment steps of nesting micro-rings within the piezoelectric thin film cavity.

[0010] Furthermore, the waveguide cladding is used to isolate acoustic-optical signals to avoid interference from the residual vibrations of the piezoelectric transducer layer on the optical sensing layer. The waveguide cladding, as an acoustic-optical signal isolation medium, prevents interference from piezoelectric residual vibrations on the micro-ring sensor, thereby improving the signal-to-noise ratio.

[0011] Furthermore, a silicon dioxide layer is provided between the substrate and the bottom electrode layer; the material of the waveguide cladding includes benzocyclobutene, polydimethylsiloxane, polymethyl methacrylate, polycarbonate, or epoxy resin; the materials of the micro-ring waveguide and the bus waveguide are chalcogenide materials.

[0012] This invention also provides a method for using a high-resolution transceiver integrated chip for robot ultrasonic positioning. By designing the pattern and size of the top electrode and acoustic cavity, the resonant frequency of the transducer unit is controlled to be f0. An electrical pulse generator provides an electrical pulse with frequency f0 to the transducer unit, and the electrical pulse is loaded onto a piezoelectric thin film layer through the top and bottom electrode layers, causing the piezoelectric thin film layer to emit ultrasonic waves with frequency f0 and radiate outwards. When a measured object is detected, an ultrasonic echo signal is generated. Simultaneously, a laser is output through a signal light generator, transmitted via optical fiber to a bus waveguide, and then to micro-ring waveguides. After receiving the ultrasonic echo signal generated by the measured object, the micro-ring waveguide converts the ultrasonic echo signal into an optical signal, which is output from the bus waveguide. A photodetector converts the optical signal carrying ultrasonic information into an electrical signal, which is finally transmitted to an information receiving and processing device. The information receiving and processing device extracts and processes the ultrasonic signal, and, with the help of corresponding algorithms, calculates the distance and relative position between the measured object and the micro-ring waveguides based on the time when the ultrasonic echo signal is received by different micro-ring waveguides and the spacing between the micro-ring waveguides. The robot can perform actions such as obstacle avoidance or grasping the object being tested based on the results.

[0013] Furthermore, when n transducer units are arranged in a regular pattern to form an ultrasonic phased array for detection, let the distance between the center of the i-th transducer unit and the object being measured be Li, and the distance between the center of the k-th transducer unit and the object being measured be the farthest, Lk; the ultrasonic waves emitted by each transducer unit have the same phase when they reach the object being measured; the ultrasonic wave propagation speed is... The delay time of the k-th transducer unit is 0, and the delay time required for the i-th transducer unit is Ti:

[0014] Based on delay time By exciting transducer units at different positions, the ultrasonic waves emitted by N transducer units are focused at different angles and positions on the object under test.

[0015] Furthermore, a distributed array composed of multiple transceiver integrated chips is used for detection. By controlling the transmission phase difference of the transducer units, a directional sound beam is synthesized, where the delay time required for the i-th transducer unit is Ti:

[0016] In the formula, The signal-to-noise ratio weighting factor. , This is an adjustable coefficient.

[0017] For distant objects, multiple transceiver integrated chips can be used to form a distributed array. Since the transceiver integrated chips of this invention are extremely small, only on the order of millimeters, using multiple chips simultaneously will not occupy excessive volume. The focusing principle of the distributed array is similar to that of a phased array; by controlling the transmission phase difference of each transducer unit, a highly directional sound beam is synthesized. The micro-ring sensor array at the receiving end synchronously acquires data, and the spatial information is reconstructed using synthetic aperture radar algorithms. Compared to a single chip, the multi-channel signal fusion of the distributed array can suppress noise and improve detection resolution. Simultaneously, the cross-detection of multiple chips can eliminate detection blind spots caused by physical obstructions in single-chip systems.

[0018] This invention also provides a method for fabricating a high-resolution transceiver integrated chip for robot ultrasonic positioning, comprising the following steps: S1. Clean the substrate and deposit the bottom electrode layer, piezoelectric thin film layer and top electrode layer on the substrate; S2. Pattern the top electrode layer using wet etching; S3. Spin-coated waveguide cladding to isolate acousto-optic signals; S4. A chalcogenide material layer was deposited using a vacuum thermal evaporation method, and then etched to form a micro-ring sensor array and a bus waveguide; S5. Spin-coated waveguide cladding; S6. A two-step etching process is used to form holes from the surface to the top and bottom electrode layers; S7. Use conductive metal as interconnect and pad metal to connect the top electrode and bottom electrode layers to the surface; S8. A cavity is formed from the back side of the substrate by deep reactive ion etching to constitute the acoustic cavity; The piezoelectric transducer layer and the optical sensing layer are independent layers, and no etching alignment is required between them during the fabrication process.

[0019] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention provides a high-resolution transceiver integrated chip for ultrasonic positioning of robots. The piezoelectric transducer layer serves as an ultrasonic transmitting device, which, together with an electric pulse generator, forms a phased-array focusing system. The micro-ring sensor array serves as an ultrasonic detection device. Relying on micro-nano manufacturing technology, it can be manufactured entirely by CMOS process. It has the advantages of high integration, high resolution, strong anti-interference ability, and small size, and can play an important role in the field of ultrasonic positioning of robots.

[0020] 2. A method for using a high-resolution transceiver integrated chip for ultrasonic positioning of a robot according to the present invention, wherein for a relatively close object to be measured, an ultrasonic phased array is formed using N transducer units, and the delay time is determined accordingly. By exciting transducer units at different locations, the ultrasonic waves emitted by the transducer array can be focused at different angles and positions on the object under test, further improving detection accuracy. For objects under test that are far away, multiple transceiver integrated chips can be used to form a distributed array. The multi-channel signal fusion of the distributed array can suppress noise and improve detection resolution. At the same time, the cross detection of multiple chips can also eliminate the detection blind spots caused by physical obstruction of a single chip.

[0021] 3. The present invention provides a method for fabricating a high-resolution transceiver integrated chip for robot ultrasonic positioning. All steps (PZT deposition, electrode etching, chalcogenide waveguide etching, and gold interconnect) are compatible with CMOS production lines, realizing piezoelectric-optical heterogeneous integration and wafer-level manufacturing, and can be mass-produced. The present invention adopts a fully planar stacked structure, and the piezoelectric transducer layer and the optical sensing layer are vertically integrated through standard CMOS processes, eliminating the need for complex alignment steps of micro-rings nested in the piezoelectric thin film cavity. Attached Figure Description

[0022] Figure 1 This is a partial structural diagram of the transceiver integrated chip in one embodiment; Figure 2 This is a schematic diagram showing the positional relationship between the piezoelectric transducer layer and the optical sensing layer of a transceiver integrated chip in one embodiment. Figure 3 This is a schematic diagram of the detection system in one embodiment; Figure 4 This is a schematic diagram of the ultrasonic phased array focusing effect at different angles and positions in another embodiment; Figure 5This is a schematic diagram of a transceiver integrated chip used for robot ranging and positioning in one embodiment. Figure 6 This is a schematic diagram of the fabrication process of a transceiver integrated chip in one embodiment.

[0023] In the attached figures: 1. Substrate; 2. Silicon dioxide layer; 3. Bottom electrode layer; 4. Piezoelectric thin film layer; 5. Waveguide lower cladding; 6. Waveguide upper cladding; 7. Top electrode; 8. Micro-ring waveguide; 9. Bus waveguide; 10. Acoustic cavity; 100. Transceiver integrated chip; 200. Signal light generator; 300. Electrical pulse generator; 400. Photodetector; 500. Information receiving and processing device; 600. Object under test. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0025] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0026] Example 1 This embodiment is an example of a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning, such as... Figure 1 and Figure 2 As shown, the structure includes a piezoelectric transducer layer, which from bottom to top includes a substrate 1, a bottom electrode layer 3, a piezoelectric thin film layer 4, and a top electrode 7; and an optical sensing layer disposed on top of the piezoelectric transducer layer, which from bottom to top includes a waveguide lower cladding layer 5, a micro-ring waveguide 8, a bus waveguide 9, and a waveguide upper cladding layer 6; the bus waveguide 9 is coupled to the micro-ring waveguide 8; and a cavity is formed at the bottom of the substrate 1 to form an acoustic cavity 10, the position of which corresponds to the position of the top electrode 7.

[0027] This embodiment presents a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning. It heterogeneously integrates a chalcogenide microring sensor on the basis of a piezoelectric micromechanical ultrasonic transducer. It combines the transmission and focusing capabilities of the piezoelectric micromechanical ultrasonic transducer for ultrasonic waves of different frequencies with the receiving capability of the microring sensor for broadband ultrasonic waves, thus realizing a highly integrated and high-resolution transceiver integrated chip 100, providing a solution for real-time obstacle avoidance and precise positioning of robots.

[0028] In this embodiment, as Figure 2 As shown, the piezoelectric transducer layer includes N transducer units, which are arranged into an ultrasonic phased array according to a predetermined pattern. There are N top electrodes 7, arranged in an array. There are also N acoustic cavities 10, with each cavity corresponding to one of the N top electrodes 7. The N top electrodes 7 are distributed in an array, and each bottom substrate 1 corresponding to a top electrode 7 has an acoustic cavity 10. The acoustic cavity 10, substrate 1, bottom electrode layer 3, piezoelectric thin film layer 4, and top electrode 7 constitute a transducer unit. The N transducer units arranged in an ultrasonic phased array can further improve the detection accuracy for nearby objects 600.

[0029] In this embodiment, as Figure 2 As shown, the optical sensing layer contains several micro-ring waveguides 8, which are arranged in a predetermined pattern to form a micro-ring sensing array. A bus waveguide 9 connects the micro-ring waveguides 8 in series, and each bus waveguide 9 is coupled to one of the micro-ring waveguides 8. The signal light generator 200 outputs laser light, which is transmitted via optical fiber to the bus waveguide 9. The bus waveguide 9 connects the micro-ring waveguides 8 in series. After receiving the ultrasonic echo signal generated by the object under test 600, the micro-ring sensor array converts it into an optical signal, which is then output from the bus waveguide 9. The photodetector 400 converts the optical signal carrying ultrasonic information into an electrical signal, which is finally transmitted to the information receiving and processing equipment.

[0030] In this embodiment, as Figure 1 As shown, the transceiver integrated chip 100 comprises, from bottom to top: a substrate 1, a bottom electrode layer 3, a piezoelectric thin film layer 4, a top electrode 7 array, a waveguide lower cladding 5, a micro-ring sensor array, a bus waveguide 9, and a waveguide upper cladding 6, forming a fully planar stacked structure. This invention employs a fully planar stacked structure: substrate 1 - bottom electrode layer 3 - piezoelectric thin film layer 4 - top electrode 7 array layer - waveguide lower cladding 5 - micro-ring sensor array and bus waveguide 9 layer - waveguide upper cladding 6; the piezoelectric transducer layer and optical sensing layer are vertically integrated using standard CMOS technology, eliminating the need for complex alignment steps where micro-rings are nested within the piezoelectric thin film cavity.

[0031] In this embodiment, the waveguide cladding 5 is used to isolate the acousto-optic signals to avoid interference from the residual vibration of the piezoelectric transducer layer on the optical sensing layer. The waveguide cladding 5 serves as an acousto-optic signal isolation medium, preventing interference from piezoelectric residual vibration on the micro-ring sensor and improving the signal-to-noise ratio.

[0032] In this embodiment, substrate 1 is a silicon substrate 1, and a silicon dioxide layer 2 is also provided between substrate 1 and bottom electrode layer 3; the material of waveguide cladding 5 includes benzocyclobutene, polydimethylsiloxane, polymethyl methacrylate, polycarbonate, or epoxy resin; the materials of micro-ring waveguide 8 and bus waveguide 9 are chalcogenide materials. Piezoelectric thin film layer 4 is a lead zirconate titanate piezoelectric thin film.

[0033] Chalcogenide materials are amorphous materials composed of chalcogen elements (such as sulfur (S), selenium (Se), tellurium (Te), etc.) and metallic or non-oxide elements. Their high refractive index, high elastic-optical coefficient, low Young's modulus, and low thermo-optical coefficient make them widely used in sensing fields. Microring sensors based on chalcogenide materials have a response bandwidth much larger than that of piezoelectric transducers, reaching 150-200MHz. According to the axial resolution calculation formula:

[0034] in For the speed of sound, The response bandwidth is optimized. Therefore, the axial resolution of the chalcogenide microring sensor is 40-50 times higher than that of the piezoelectric transducer. Furthermore, the optical response speed of the chalcogenide microring sensor reaches the picosecond level, with no mechanical residual vibration and an extremely small detection blind zone. Its quality factor (Q value) reaches 10. 5 ~10 6 This technology can detect extremely minute displacements, and its all-optical signal transmission is naturally resistant to electromagnetic interference. The unit size can be reduced to 10~100 μm, supporting high-density array integration. Micro-ring sensors are passive detectors and lack the ability to generate ultrasound. In this embodiment, a transceiver integrated chip is proposed that heterogeneously integrates a piezoelectric micromechanical ultrasonic transducer and a chalcogenide micro-ring sensor. This combines the advantages of both in the field of ultrasonic detection, can be manufactured using CMOS technology, and has advantages such as high integration and high resolution. Furthermore, it can utilize the focusing effect of an ultrasonic phased array to achieve precise object positioning.

[0035] Working Principle: By designing the pattern and size of the top electrode 7 and the acoustic cavity 10, the resonant frequency of the transducer unit is controlled to be f0. The electrical pulse generator 300 provides electrical pulses with a frequency of f0 to the transducer unit. The electrical pulses are loaded onto the piezoelectric thin film layer 4 through the top electrode 7 and the bottom electrode layer 3, causing the piezoelectric thin film layer 4 to emit ultrasonic waves with a frequency of f0 outward. Subsequently, the object under test 600 generates an ultrasonic echo signal. At the same time, the signal light generator 200 outputs a laser, which is transmitted to the bus waveguide 9 via optical fiber. The bus waveguide 9 connects the micro-ring sensor array in series. After receiving the ultrasonic echo signal generated by the object under test 600, the micro-ring sensor array converts it into an optical signal, which is output by the bus waveguide 9. The photodetector 400 converts the optical signal carrying ultrasonic information into an electrical signal and transmits it to the information receiving and processing equipment. The ultrasonic signal is extracted and processed. With the help of the corresponding algorithm, the distance and relative position between the object under test 600 and the micro-ring waveguide 8 are calculated based on the time when the ultrasonic echo signal is received by different micro-ring waveguides 8 and the spacing between the micro-ring waveguides 8.

[0036] This embodiment provides a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning. The piezoelectric transducer layer and the optical sensing layer are vertically stacked, with no special relative positional relationship in the plane, eliminating the need for alternating / concentric circle design. The transceiver integrated chip 100 provided in this embodiment can also employ a multi-chip distributed architecture for detection and positioning, and there is no physical coplanar arrangement relationship between the chips.

[0037] This embodiment provides a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning. It is an ultrasonic ranging and positioning chip based on the integration of a piezoelectric micromechanical ultrasonic transducer and an optical chalcogenide microring sensor. It is particularly suitable for fields such as robots, drones, and micro medical devices that are sensitive to spatial perception accuracy, system integration, and power consumption.

[0038] Example 2 This embodiment is an example of using a high-resolution transceiver integrated chip 100 for ultrasonic positioning of a robot. This embodiment uses the transceiver integrated chip 100 provided in Embodiment 1. In this embodiment, the resonant frequency of the transducer unit is controlled to be f0 by designing the pattern and size of the top electrode 7 and the acoustic cavity 10. An electrical pulse with frequency f0 is provided to the transducer unit by an electrical pulse generator 300, and the electrical pulse is loaded onto the piezoelectric thin film layer 4 through the top electrode 7 and the bottom electrode layer 3, so that the piezoelectric thin film layer 4 emits ultrasonic waves with frequency f0 and radiates outward. When the object under test 600 is detected, an ultrasonic echo signal is generated. At the same time, a laser is output by a signal light generator 200, transmitted through an optical fiber to the bus waveguide 9, and then transmitted to the micro-ring waveguide 8. After receiving the ultrasonic echo signal generated by the object under test 600, the micro-ring waveguide 8 converts the ultrasonic echo signal into an optical signal, which is output by the bus waveguide 9. The optical signal carrying ultrasonic information is converted into an electrical signal by a photodetector 400, and finally transmitted to the information receiving and processing device 500. The information receiving and processing device 500 extracts and processes the ultrasonic signals. Using appropriate algorithms, it calculates the distance and relative position between the object under test 600 and the micro-ring waveguides 8 based on the time it takes for the ultrasonic echo signals to be received by different micro-ring waveguides 8 and the spacing between the micro-ring waveguides 8. The robot can then perform obstacle avoidance or grasping actions on the object under test 600 based on the results.

[0039] After preliminary detection, to further improve detection accuracy, for nearby objects 600, a phased array can be used to focus ultrasonic waves onto the surface of the object 600 for more detailed detection. In this embodiment, n transducer units are arranged in a regular pattern to form an ultrasonic phased array for detection. Based on the preliminary detection, the approximate position of the object 600 and the distance from the object 600 to each transducer unit are obtained. Assuming the distance between the center of the i-th transducer unit and the object 600 is Li, and the distance between the center of the k-th transducer unit and the object 600 is the farthest, Lk, and the ultrasonic waves emitted by each transducer unit have the same phase when they reach the object 600, then transducer units farther away need to be excited earlier than those closer, and different delay excitation times need to be set for transducer units at different positions. Assuming the ultrasonic propagation speed is... The delay time of the k-th transducer unit is 0, and the delay time required for the i-th transducer unit is Ti:

[0040] Based on delay time By exciting transducer units at different positions, the ultrasonic waves emitted by N transducer units are focused onto the object under test at different angles and positions within a 60° radius. Figure 4As shown. In addition to planar structures, piezoelectric transducer layers can also be fabricated on substrates 1 with spherical or parabolic structures. Micro-ring sensing arrays and bus waveguides 9 can be fabricated on the spherical or parabolic surfaces using two-photon polymerization printing technology and semiconductor processing technology to further enhance the focusing effect.

[0041] For the object 600 that is far away, multiple transceiver integrated chips 100 can be used to form a distributed array for detection. Since the transceiver integrated chip 100 of the present invention is extremely small, only on the order of millimeters, multiple transceiver integrated chips 100 can be used at the same time without taking up too much space.

[0042] In this embodiment, the focusing principle of the distributed array is similar to that of the phased array. By controlling the transmission phase difference of the transducer units, a directional sound beam is synthesized. The receiving end micro-ring sensor array synchronously collects data, and the spatial information is reconstructed by combining it with the synthetic aperture radar algorithm. To adapt to signal quality fluctuations in the robot's dynamic environment, this embodiment introduces a signal-to-noise ratio weighting factor. Its value is proportional to the real-time signal-to-noise ratio (SNR) of each chip. At this point, the delay time... The calculation formula becomes:

[0043] In the formula, The signal-to-noise ratio weighting factor. , This is an adjustable coefficient.

[0044] By normalizing weights With adjustable coefficient Dynamically allocate the contribution weight of each chip in the synthesized aperture, high Chip-driven positioning results improve accuracy; low The chip is suppressed to eliminate errors caused by occlusion or noise; It adaptively adjusts to the ambient noise level. Compared to a single chip, the multi-channel signal fusion of the distributed array can suppress noise and improve detection resolution. At the same time, the cross-detection of multiple chips can also eliminate detection blind spots caused by physical obstruction in a single chip.

[0045] Example 3 This embodiment provides a detection system, such as Figure 3 As shown, it includes the transceiver integrated chip 100, signal light generator 200, electrical pulse generator 300, photodetector 400, and information receiving and processing equipment provided in Embodiment 1. Its working principle is similar to that of Embodiment 2. In this embodiment, the transceiver integrated chip 100 can be configured as a phased array composed of N transducer units to achieve distance detection and positioning, depending on actual needs; or multiple transceiver integrated chips 100 can be configured as a distributed array to achieve distance detection and positioning.

[0046] Example 4 This embodiment is an example of a method for fabricating a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning, used to fabricate the transceiver integrated chip 100 provided in Embodiment 1, such as... Figure 6 As shown, the specific steps include: S1. Clean substrate 1, and deposit bottom electrode layer 3, piezoelectric thin film layer 4 and top electrode layer 7 on substrate 1; S2. The top electrode is patterned in 7 layers using wet etching; S3. The spin-coated waveguide cladding 5 is made of polymers such as benzocyclobutene (BCB), polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), polycarbonate (PC), and epoxy resin (SU-8). This layer also serves as an acoustic-optical signal isolation medium, preventing piezoelectric residual vibrations from interfering with the micro-ring sensing and improving the signal-to-noise ratio. S4. A chalcogenide material layer is deposited using a vacuum thermal evaporation method, and a micro-ring sensing array and a bus waveguide 9 are formed by etching. The piezoelectric transducer layer and the optical sensing layer are independent layers, and no etching alignment is required between them during the fabrication process. S5. Spin-coated PDMS as waveguide cladding 6; S6. A hole is formed from the surface to the top electrode layer 7 and the bottom electrode layer 3 through a two-step etching process; S7. Using gold (Au) as the interconnect and pad metal, the top electrode 7 and the bottom electrode layer 3 are connected to the surface; S8. A cavity is formed from the back side of the substrate 1 by deep reactive ion etching to form an acoustic cavity 10, thereby defining the effective flexural diameter and boundary of each piezoelectric transducer unit and improving acoustic performance.

[0047] This embodiment provides a method for fabricating a high-resolution transceiver integrated chip 100 for robot ultrasonic positioning. All steps (PZT deposition, electrode etching, chalcogenide waveguide etching, and gold interconnect) are compatible with CMOS production lines, realizing piezoelectric-optical heterogeneous integration and wafer-level manufacturing, and can be mass-produced. The present invention adopts a fully planar stacked structure, and the piezoelectric transducer layer and the optical sensing layer are vertically integrated through standard CMOS processes, eliminating the need for complex alignment steps of micro-rings nested in the piezoelectric thin film cavity.

[0048] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A high-resolution transceiver integrated chip for ultrasonic positioning of robots, characterized in that, It includes a piezoelectric transducer layer, which from bottom to top includes a substrate (1), a bottom electrode layer (3), a piezoelectric thin film layer (4), and a top electrode (7). And an optical sensing layer integrated on top of the piezoelectric transducer layer, comprising, from bottom to top: waveguide lower cladding (5); micro-ring waveguide (8) and bus waveguide (9); and waveguide upper cladding (6); the bus waveguide (9) is coupled to the micro-ring waveguide (8); a cavity is formed at the bottom of the substrate (1) to form an acoustic cavity (10), the position of the acoustic cavity (10) corresponds to the position of the top electrode (7).

2. The high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 1, characterized in that, The piezoelectric transducer layer includes N transducer units, which are arranged in an ultrasonic phased array according to a set rule. There are N top electrodes (7), which are arranged in an array according to a set rule. There are N acoustic cavities (10). The positions of the N acoustic cavities (10) correspond one-to-one with the positions of the N top electrodes (7).

3. The high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 2, characterized in that, The optical sensing layer is provided with a plurality of micro-ring waveguides (8), and the plurality of micro-ring waveguides (8) form a micro-ring sensing array according to a set pattern. The bus waveguide (9) connects the plurality of micro-ring waveguides (8) in series, and the bus waveguide (9) is coupled to the micro-ring waveguides (8) respectively.

4. The high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 3, characterized in that, The transceiver integrated chip (100) includes, from bottom to top: a substrate (1), a bottom electrode layer (3), a piezoelectric thin film layer (4), a top electrode (7) array, a waveguide lower cladding (5), a micro-ring sensing array, a bus waveguide (9), and a waveguide upper cladding (6), forming a fully planar stacked structure.

5. The high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 3, characterized in that, The waveguide cladding (5) is used to isolate acoustic and optical signals to avoid interference from the residual vibration of the piezoelectric transducer layer to the optical sensing layer.

6. The high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 3, characterized in that, A silicon dioxide layer (2) is provided between the substrate (1) and the bottom electrode layer (3); the material of the waveguide cladding (5) includes benzocyclobutene, polydimethylsiloxane, polymethyl methacrylate, polycarbonate, or epoxy resin; the materials of the micro-ring waveguide (8) and the bus waveguide (9) are chalcogenide materials.

7. A method of using the high-resolution transceiver integrated chip for robot ultrasonic positioning as described in any one of claims 1 to 6, characterized in that, By designing the pattern and size of the top electrode (7) and the acoustic cavity (10), the resonant frequency of the transducer unit is controlled to be f0. The transducer unit is provided with an electric pulse of frequency f0 by the electric pulse generator (300), and the electric pulse is loaded onto the piezoelectric thin film layer (4) through the top electrode (7) and the bottom electrode layer (3), so that the piezoelectric thin film layer (4) emits ultrasonic waves of frequency f0 and radiates outward. When the object under test (600) is detected, an ultrasonic echo signal is generated. At the same time, the laser is output by the signal light generator (200), transmitted to the bus waveguide (9) through the optical fiber, and then transmitted to the micro-ring waveguide (8). After the micro-ring waveguide (8) receives the ultrasonic echo signal generated by the object under test (600), it converts the ultrasonic echo signal into an optical signal and outputs it through the bus waveguide (9). The optical signal with ultrasonic information is converted into an electrical signal by the photodetector (400) and finally transmitted to the information receiving and processing device (500).

8. The method of using the high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 7, characterized in that, When n transducer units are arranged in a regular pattern to form an ultrasonic phased array for detection, let the distance between the center of the i-th transducer unit and the object under test (600) be Li, and the distance between the center of the k-th transducer unit and the object under test (600) be the farthest, Lk; the ultrasonic waves emitted by each transducer unit have the same phase when they reach the object under test (600); the ultrasonic wave propagation speed is... The delay time of the k-th transducer unit is 0, and the delay time required for the i-th transducer unit is Ti: Based on delay time By exciting transducer units at different positions, the ultrasonic waves emitted by N transducer units are focused at different angles and positions on the object under test.

9. The method of using the high-resolution transceiver integrated chip for robot ultrasonic positioning according to claim 8, characterized in that, A distributed array composed of multiple transceiver integrated chips is used for detection. By controlling the transmission phase difference of the transducer units, a directional sound beam is synthesized, where the delay time required for the i-th transducer unit is Ti: In the formula, The signal-to-noise ratio weighting factor. , This is an adjustable coefficient.

10. A method for fabricating a high-resolution transceiver integrated chip for robot ultrasonic positioning as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Clean the substrate (1) and deposit the bottom electrode layer (3), the piezoelectric thin film layer (4) and the top electrode layer (7) on the substrate (1); S2. Pattern the top electrode (7) layer using wet etching; S3. Spin-coating the waveguide cladding (5) to isolate acoustic and optical signals; S4. A chalcogenide material layer was deposited by vacuum thermal evaporation and etched to form a micro-ring sensor array and a bus waveguide (9). S5. Spin-coated waveguide cladding (6); S6. Through a two-step etching process, holes are formed from the surface to the top electrode (7) layer and the bottom electrode layer (3); S7. Using conductive metal as interconnect and pad metal, the top electrode (7) and the bottom electrode layer (3) are connected to the surface; S8. A cavity is formed by etching from the back side of the substrate (1) using a deep reactive ion etching process to form the acoustic cavity (10). The piezoelectric transducer layer and the optical sensing layer are independent layers, and no etching alignment is required between them during the fabrication process.

Images