Positioning device, scanning equipment and scanning probe equipment

Abstract

The invention discloses a positioning device, scanning equipment and scanning probe equipment, relates to the technical field of high-precision positioning equipment, and aims to solve the problem that an existing piezoelectric nanometer positioning device cannot have a large stroke and a high bandwidth at the same time. The positioning device comprises a base, and the base is connected with a first movable platform and a second movable platform which are arranged in a nested mode; the first movable platform is located in the second movable platform, the second movable platform is connected with the base and the first movable platform through connecting structures, at least one piezoelectric actuator is used for driving the second movable platform to move relative to the base in the first direction, and at least one piezoelectric actuator is used for driving the second movable platform to move relative to the base in the second direction. The at least one piezoelectric actuator is used for driving the first movable platform to move along the first direction relative to the second movable platform, compared with a single piezoelectric actuator with the same size, the device can realize the large-stroke characteristic, and the bandwidth characteristic of the piezoelectric actuator cannot be reduced due to the increase of the number of the piezoelectric actuators, so that the device can be used for realizing the large-stroke characteristic. Therefore, the high bandwidth characteristic can be realized at the same time.

Description

Technical Field

[0001] This application relates to the technical field of high-precision positioning devices, and more specifically, to a positioning device, a scanning device, and a scanning probe device. Background Art

[0002] In the fields of micro-nano positioning, scanning, and detection, piezoelectric nano-positioning stages are widely used. A piezoelectric nano-positioning stage is a device that utilizes the piezoelectric effect to achieve precise positioning. The piezoelectric effect refers to the phenomenon that certain materials generate electric charges when subjected to mechanical stress, and conversely, generate mechanical deformation when subjected to an electric field. This property makes piezoelectric materials very suitable for actuators that precisely control displacement.

[0003] In engineering, piezoelectric nano-positioning stages are required to have both a large stroke and a high bandwidth simultaneously. Since the stroke and bandwidth of a piezoelectric nano-actuator are inversely related, the design of a piezoelectric nano-positioning stage with both a large stroke and a high bandwidth has become a technical challenge.

[0004] Therefore, how to solve the problem that existing piezoelectric nano-positioning stages cannot simultaneously possess the performance of a large stroke and a high bandwidth is an urgent problem to be solved. Summary of the Invention

[0005] This application discloses a positioning device, a scanning device, and a scanning probe device, which have both the performance of a large stroke and a high bandwidth.

[0006] In a first aspect, this application provides a positioning device, including: a base, the base is connected with a first moving platform and a second moving platform arranged in a nested manner, the first moving platform is located inside the second moving platform, the second moving platform is connected to the base and the first moving platform through connection structures respectively, at least two piezoelectric drivers, wherein, at least one piezoelectric driver is used to drive the second moving platform to move relative to the base along a first direction, and at least one piezoelectric driver is used to drive the first moving platform to move relative to the second moving platform along the first direction. The first moving platform, the second moving platform, and the base are arranged in sequence from the inside to the outside. The second moving platform is connected to the base and the first moving platform through connection structures respectively, providing a moving space for the first moving platform and the second moving platform. By setting multiple piezoelectric drivers, compared with a single piezoelectric driver of the same volume, the large-stroke characteristic can be achieved. At the same time, because the bandwidth characteristic of the piezoelectric driver will not be superimposed due to the increase in the number of piezoelectric drivers, when two or more piezoelectric drivers are set, the bandwidth will not be superimposed, that is, the bandwidth will not be reduced due to the increase in the number of piezoelectric drivers. Therefore, compared with setting a single piezoelectric driver, the high-bandwidth characteristic and the large-stroke characteristic can be achieved simultaneously.

[0007] In a possible implementation, at least two piezoelectric actuators are located on the same center line of the base. Since at least two piezoelectric actuators are arranged on the same center line of the base, when the piezoelectric actuators are energized and mechanically deformed, they can stably drive the corresponding first moving platform and second moving platform to move nanometers in the first direction as a whole, without the problems of imbalance and instability during the movement of the first moving platform and the second moving platform, thereby increasing the stability and balance of the piezoelectric actuators driving the first moving platform and the second moving platform.

[0008] In a possible implementation, it further includes at least one sensor for detecting the displacement of the first moving platform and the second moving platform moving in the first direction. Due to the hysteresis of the piezoelectric actuator itself, accurate positioning cannot be achieved. By setting the sensor, accurate detection of the moving positions of the first moving platform and the second moving platform can be realized, so as to improve the precise control of the moving displacements of the first moving platform and the second moving platform, thereby achieving accurate positioning.

[0009] In a possible implementation, at least one sensor and at least two piezoelectric actuators are located on the same center line of the base. Setting the sensor and the piezoelectric actuator on the same center line of the base can balance the overall weight, avoid the offset of the overall center of gravity, and enable the first moving platform and the second moving platform to move smoothly under the drive of the piezoelectric actuator, thereby improving the stability and detection accuracy during the overall movement.

[0010] In a possible implementation, there are two sensors. One sensor is arranged inside the base and is used to detect the displacement of the second moving platform relative to the base in the first direction. The other sensor is arranged inside the second moving platform and is used to detect the displacement of the first moving platform relative to the second moving platform in the first direction. One end of the sensor arranged inside the base is connected to the inside of the base, and the other end has a clearance fit with the second moving platform. This sensor will not move during use and provides a reference for measuring the moving position of the second moving platform. One end of the sensor arranged inside the second moving platform is connected to the inside of the second moving platform, and the other end has a clearance fit with the first moving platform. This sensor will move during use, but the sensor arranged inside the base will never move during use. Therefore, by combining the moving positions of the corresponding moving platforms detected by the two sensors, the actual moving position of the first moving platform can be accurately obtained. The two sensors and the corresponding piezoelectric actuators form a closed-loop control to improve the detection accuracy.

[0011] In a possible implementation, it further includes a control device. The control device is respectively connected to the sensor and the piezoelectric actuator. The control device is used to convert the signal from the sensor into a control signal to control the circuit to output a voltage to the piezoelectric actuator. During use, the operation state of the piezoelectric actuator is controlled in real time by the control device, the moving displacement of the moving platform is detected in real time by the sensor, and the displacement information detected in real time is fed back to the control device. The voltage output by the circuit to the piezoelectric actuator is further adjusted in real time by the control device, so as to adjust the operation state of the piezoelectric actuator. In this way, a closed-loop control is formed between the sensor and the piezoelectric actuator to improve the positioning accuracy.

[0012] In a possible implementation, the first moving platform and the second moving platform are arranged in a zigzag shape, and the second moving platform and the base are arranged in a zigzag shape. Mounting holes are provided on the axis and / or diagonal line of the base and the first moving platform. The mounting holes of the base are used to fix the base, and the mounting holes of the first moving platform are used to fix the component to be positioned. The shapes of the first moving platform, the second moving platform and the base are set to simple structures to simplify the overall structure, reduce the processing difficulty in the actual production process, and thus reduce the production cost. The mounting holes of the base are used to fix the base, and the mounting holes of the first moving platform are used to fix the component to be positioned. During use, the component to be positioned is fixed on the first moving platform through the locking nut and the mounting hole on the first moving platform, preparing for the subsequent scanning and detection process.

[0013] In a possible implementation, the connecting structure is a flexible structure. The flexible structure includes at least two single-degree-of-freedom flexible hinges, and the degree-of-freedom direction of the flexible hinge is the first direction. The flexible hinge can undergo elastic deformation along the first direction under the driving action of the piezoelectric actuator. Since the direction of the elastic deformation of the flexible hinge is consistent with the moving direction of the moving platform, the moving platform can be made to move along the first direction at the nanoscale under the drive of the piezoelectric actuator. Moreover, in order to enable the piezoelectric actuator to drive the first moving platform and the second moving platform to move along the first direction at the nanoscale, the direction of the elastic deformation of the flexible hinge must be the first direction.

[0014] In a possible implementation, the flexible hinge is provided on the first moving platform or the second moving platform. Whether the flexible hinge is provided on the first moving platform or the second moving platform, as long as the direction of the elastic deformation of the flexible hinge is consistent with the moving direction of the first moving platform and the second moving platform, the first moving platform and the second moving platform can be driven to move by the flexible hinge.

[0015] In a possible implementation, the flexible hinges are symmetrically arranged along a first direction and a second direction perpendicular to the first direction within the end face of the base. The flexible hinges between the first moving platform and the second moving platform, and between the second moving platform and the base can all be set as the same type of flexible hinge, so that the flexible hinges are symmetrically arranged in the first direction and the second direction. In this way, the stress borne by all the flexible hinges can be made consistent, and the stress can be evenly dispersed, which can maximize the stability and balance of the whole during the movement process.

[0016] In a possible implementation, a flexible hinge includes at least two first flexible hinge branches and at least two second flexible hinge branches. The at least two first flexible hinge branches extend along the first direction, and the at least two second flexible hinge branches extend along the second direction. The extension length of the first flexible hinge branches is much smaller than that of the second flexible hinge branches. The first flexible hinge branches and the second flexible hinge branches are alternately connected in sequence to form a serpentine flexible hinge. Such a flexible hinge has a relatively high stress and can improve the stability and balance of the whole during the movement process.

[0017] In a possible implementation, a flexible hinge includes three first flexible hinge branches and at least three second flexible hinge branches. The three first flexible hinge branches extend along the first direction, and the at least three second flexible hinge branches extend along the second direction and are arranged in parallel. The first ends of the at least three second flexible hinge branches are all connected to the same first flexible hinge branch, and the second ends of the two second flexible hinge branches located on the outermost side of the same column are connected to the corresponding first flexible hinge branches. Such a flexible hinge has a relatively high stress and can improve the stability and balance of the whole during the movement process.

[0018] In a possible implementation, the at least three second flexible hinge branches are arranged at equal intervals along the first direction. Arranging the second flexible hinge branches at equal intervals along the first direction can improve the stability of the movement of the moving platform.

[0019] In a second aspect, the present application provides a scanning device, including: a scanning lens, which is detachably arranged on the positioning device as described in any one of the above. The scanning lens is located in the middle of the first moving platform. When using this device, the piezoelectric driver of the positioning device drives the moving platform to move, thereby driving the scanning lens to move synchronously. The displacement output by the piezoelectric driver is amplified by the flexible structure of the positioning device, and the moving displacement of the moving platform is detected in real time by the sensor of the positioning device, and the displacement information detected in real time is fed back to the control device of the positioning device. The voltage output by the control device to the piezoelectric driver is further adjusted in real time, thereby adjusting the operating state of the piezoelectric driver. In this way, a closed-loop control is formed between the sensor and the piezoelectric driver to improve the accuracy of the scanning of the scanning lens.

[0020] In a third aspect, the present application provides a scanning probe device, including: a probe, which is detachably arranged on the positioning device as described in any one of the above through an adapter. The probe is located in the middle of the first moving platform. When using this device, the piezoelectric actuator of the positioning device drives the moving platform to move, thereby driving the probe to move synchronously. The flexible structure of the positioning device amplifies the displacement output by the piezoelectric actuator, and the sensor of the positioning device detects the moving displacement of the moving platform in real time, and feeds the displacement information detected in real time back to the control device of the positioning device. The control device further adjusts the voltage output to the piezoelectric actuator by the piezoelectric actuator circuit in real time, so as to adjust the operating state of the piezoelectric actuator. In this way, a closed-loop control is formed between the sensor and the piezoelectric actuator to improve the accuracy of probe scanning. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a top view of the positioning device provided by the embodiment of the present application;

[0023] Figure 2 It is a top view of the first flexible hinge provided by the embodiment of the present application;

[0024] Figure 3 It is Figure 2 a top view of another state;

[0025] Figure 4 It is a top view of the second flexible hinge provided by the embodiment of the present application;

[0026] Figure 5 It is Figure 4 a top view of another state;

[0027] Figure 6 It is a top view of the third flexible hinge provided by the embodiment of the present application;

[0028] Figure 7 It is Figure 6 a top view of another state;

[0029] Figure 8 It is a top view of the positioning device provided by the embodiment of the present application applied to a scanning device;

[0030] Figure 9 It is a top view of the positioning device provided by the embodiment of the present application applied to a scanning probe device.

[0031] Description of the reference numerals:

[0032] 1 - Base

[0033] 2 - First moving platform

[0034] 3 - Second moving platform

[0035] 4 - Flexible hinge, 41 - First flexible hinge chain, 42 - Second flexible hinge chain

[0036] 5 - Piezoelectric actuator

[0037] 6 - Sensor

[0038] 7 - Scanning lens

[0039] 8 - Probe

[0040] 9 - Adapter Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0042] In the present application, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0043] The present application provides a positioning device, a scanning device, and a scanning probe device, which are mainly applied to optical microscopes, scanning probe microscopes, semiconductor manufacturing equipment, including but not limited to semiconductor manufacturing, biomedical research, materials science, and precision engineering, etc.

[0044] Please refer to Figure 1, A positioning device, comprising a base 1, the base 1 is connected with a first moving platform 2 and a second moving platform 3 which are nested. The first moving platform 2 is located inside the second moving platform 3. The first moving platform 2, the second moving platform 3 and the base 1 are arranged in sequence from inside to outside. The second moving platform 3 is connected to the base 1 and the first moving platform 2 through connection structures. By setting the connection structures, a moving space is provided for the first moving platform 2 and the second moving platform 3. The connection structures are specifically flexible structures; there are at least two piezoelectric actuators 5. Among them, at least one piezoelectric actuator 5 is used to drive the second moving platform 3 to move relative to the base 1 along a first direction. Since the second moving platform 3 is connected to the base 1 and the first moving platform 2 through connection structures, when the piezoelectric actuator 5 drives the second moving platform 3 to move relative to the base 1 along the first direction, the first moving platform 2 can be driven to move synchronously through the connection structure between the second moving platform 3 and the first moving platform 2, so that the first moving platform 2 moves in the nanoscale along the first direction. And at least one piezoelectric actuator 5 is used to drive the first moving platform 2 to move relative to the second moving platform 3 along the first direction. Among them, the first direction can be the length direction of the base 1. In practical applications, there is no limitation on the specific direction of the first direction.

[0045] The first moving platform 2, the second moving platform 3 and the base 1 are arranged in sequence from inside to outside. The second moving platform 3 is connected to the base 1 and the first moving platform 2 through connection structures, providing a moving space for the first moving platform 2 and the second moving platform 3. By setting multiple piezoelectric actuators 5 with the same volume, compared with a single piezoelectric actuator 5 of the same volume, the large-stroke characteristic can be achieved. At the same time, since the bandwidth characteristic of the piezoelectric actuator 5 will not be superimposed due to the increase in the number of piezoelectric actuators 5, when two or more piezoelectric actuators 5 with the same volume are set, the bandwidth will not be superimposed. That is to say, the bandwidth will not be reduced due to the increase in the number of piezoelectric actuators 5. Therefore, compared with setting a single piezoelectric actuator 5, the high-bandwidth characteristic and the large-stroke characteristic can be achieved simultaneously.

[0046] Exemplarily, there are two piezoelectric actuators 5, and the volumes of the two piezoelectric actuators 5 are different. One piezoelectric actuator 5 has a large volume and can be used to achieve the large-stroke characteristic, and the other piezoelectric actuator 5 has a small volume and can be used to achieve the high-bandwidth characteristic. In this case, in one embodiment, the piezoelectric actuator 5 that drives the second moving platform 3 to move relative to the base 1 along the first direction can achieve the large-stroke characteristic, and the piezoelectric actuator 5 that drives the first moving platform 2 to move relative to the second moving platform 3 along the first direction can achieve the large-bandwidth characteristic; in another embodiment, the piezoelectric actuator 5 that drives the second moving platform 3 to move relative to the base 1 along the first direction can achieve the large-bandwidth characteristic, and the piezoelectric actuator 5 that drives the first moving platform 2 to move relative to the second moving platform 3 along the first direction can achieve the large-stroke characteristic.

[0047] Exemplarily, two piezoelectric actuators 5 are provided, and the two piezoelectric actuators 5 have the same specifications. One of the piezoelectric actuators 5 drives the second moving platform 3 to move relative to the base 1 in the first direction, and the other piezoelectric actuator 5 is used to drive the first moving platform 2 to move relative to the second moving platform 3 in the first direction. Compared with the case where a single piezoelectric actuator 5 can achieve high-bandwidth characteristics but cannot achieve large-stroke characteristics under the same volume, by setting two piezoelectric actuators 5, displacement superposition can be achieved to realize the characteristic of large stroke, and the bandwidth characteristics of the piezoelectric actuator 5 will not be superimposed. Therefore, the characteristics of large stroke and high bandwidth can be taken into account simultaneously.

[0048] Exemplarily, when three piezoelectric actuators 5 are provided, two of the three piezoelectric actuators 5 have the same volume. One piezoelectric actuator 5 with a volume different from the other two drives the second moving platform 3 to move relative to the base 1 in the first direction, and the two piezoelectric actuators 5 with the same volume are used to drive the first moving platform 2 to move relative to the second moving platform 3 in the first direction. Or, the two piezoelectric actuators 5 with the same volume drive the second moving platform 3 to move relative to the base 1 in the first direction, and one piezoelectric actuator 5 with a different volume is used to drive the first moving platform 2 to move relative to the second moving platform 3 in the first direction. Two of the three piezoelectric actuators 5 are set to have the same volume to ensure the consistency of the installation of the piezoelectric actuator 5. In this case, the piezoelectric actuator 5 that drives the second moving platform 2 to move relative to the base 1 in the first direction can achieve a high-bandwidth dynamic response, and the piezoelectric actuator 5 that drives the first moving platform 2 to move relative to the second moving platform 3 in the first direction can achieve a large-stroke dynamic response. Or, the piezoelectric actuator 5 that drives the second moving platform 2 to move relative to the base 1 in the first direction can achieve a large-stroke dynamic response, and the piezoelectric actuator 5 that drives the first moving platform 2 to move relative to the second moving platform 3 in the first direction can achieve a high-bandwidth dynamic response. The bandwidth characteristics of the piezoelectric actuator 5 will not be superimposed. Therefore, by setting three piezoelectric actuators 5 to directly drive the corresponding second moving platform 3 and the first moving platform 2 to move at the nanometer level, the three piezoelectric actuators 5 can achieve large-stroke and high-bandwidth dynamic responses, so that the positioning device can take into account the functions of large stroke and high bandwidth. Or, setting three piezoelectric actuators 5 with the same volume and high-bandwidth characteristics will not cause bandwidth superposition and can achieve stroke superposition, compared with setting a single piezoelectric actuator 5, it can achieve high-bandwidth characteristics and large-stroke characteristics at the same time.

[0049] Among them, in practical applications, the number of the piezoelectric actuators 5 is not limited, as long as the above technical effects can be achieved.

[0050] In practical applications, the piezoelectric actuator 5 is installed between the first moving platform 2 and the second moving platform 3, and between the second moving platform 3 and the base 1. When installing, the first moving platform 2 and the second moving platform 3 apply a certain pre-tightening force to the piezoelectric actuator 5 between them to fix the position of the piezoelectric actuator 5, and the second moving platform 3 and the base 1 apply a certain pre-tightening force to the piezoelectric actuator 5 between them to fix the position of the piezoelectric actuator 5. Moreover, during the process of mechanical expansion and contraction of the piezoelectric actuator 5 due to the magnitude of the applied voltage, the piezoelectric actuator 5 always remains between the first moving platform 2 and the second moving platform 3, and between the second moving platform 3 and the base 1, without falling off.

[0051] When using the positioning device, one of the piezoelectric actuators 5 can be controlled to operate to drive the first moving platform 2 to move at the nanometer level. Among them, the piezoelectric actuator can be a piezoelectric ceramic actuator, and the working principle of the piezoelectric ceramic is based on the piezoelectric effect. The piezoelectric effect refers to the fact that when some media are subjected to mechanical pressure, they will undergo shape changes such as compression or elongation, causing the surface of the medium to become charged, which is the positive piezoelectric effect. The piezoelectric ceramic actuator utilizes the piezoelectric effect to convert the input electrical signal (usually voltage) into mechanical displacement. Specifically, when a voltage is applied to the piezoelectric ceramic, the ceramic will deform and generate mechanical displacement. This displacement can be very precisely controlled because the response speed of the piezoelectric effect is extremely fast, and there is a good linear relationship between the displacement amount and the input voltage.

[0052] Furthermore, the piezoelectric actuator 5 is set based on the inverse piezoelectric effect of the piezoelectric ceramic. An external voltage is applied to the piezoelectric actuator 5 to cause the piezoelectric actuator 5 to undergo mechanical contraction, thereby driving the first moving platform 2 to move. By changing the magnitude of the applied voltage, the contraction amount of the piezoelectric actuator 5 is controlled, thereby controlling the moving position of the first moving platform 2.

[0053] On this positioning device, the workpiece to be positioned can be installed and fixed to drive the workpiece to be positioned for nano-scale scanning and positioning. This positioning device can be applied to measuring equipment, detection equipment, and processing equipment, and its function is high-speed and high-precision scanning and positioning at the nano-scale.

[0054] In a possible implementation manner, at least two piezoelectric actuators 5 are located on the same center line of the base 1.

[0055] Exemplarily, when there are two piezoelectric actuators 5, one piezoelectric actuator 5 is arranged between the first moving platform 2 and the second moving platform 3, and the other piezoelectric actuator 5 is arranged between the second moving platform 3 and the base 1. The two piezoelectric actuators 5 are arranged on the same center line of the base 1. Since the two piezoelectric actuators 5 are arranged on the same center line of the base, when the piezoelectric actuators 5 are powered on and undergo mechanical deformation, they will stably drive the corresponding first moving platform 2 and the second moving platform 3 to move nanometers in the first direction as a whole, and there will be no problem of imbalance and instability during the movement of the first moving platform 2 and the second moving platform 3, thereby increasing the stability and balance of the piezoelectric actuators 5 in driving the first moving platform 2 and the second moving platform 3. Wherein, the extending direction of this center line is consistent with the first direction. To ensure that the first moving platform 2 and the second moving platform 3 can move nanometers in the first direction.

[0056] In one embodiment, based on another center line of the base 1, the two piezoelectric actuators 5 can be arranged on the same side of this center line, or arranged on both sides of this center line. The extending direction of this other center line here is consistent with the second direction, and the second direction is specifically the direction perpendicular to the first direction within the end face of the base 1. For example, assuming the planar shape of the base 1 is rectangular, when the first direction is the length direction of the base 1, the second direction is the width direction of the base 1.

[0057] In one possible implementation manner, it further includes at least one sensor 6 for detecting the displacement of the first moving platform 2 and the second moving platform 3 moving along the first direction.

[0058] Exemplarily, because the piezoelectric actuator 5 itself has hysteresis, by setting the sensor 6, the precise detection of the moving positions of the first moving platform 2 and the second moving platform 3 can be realized, so as to improve the precise control of the moving displacement of the first moving platform 2 and the second moving platform 3, thereby realizing precise positioning.

[0059] In one possible implementation manner, it further includes a control device. The control device is respectively connected to the sensor 6 and the piezoelectric actuator 5. The control device is used to convert the signal from the sensor 6 into a control signal to control the circuit to output voltage to the piezoelectric actuator 5.

[0060] Exemplarily, during the use process, the operation state of the piezoelectric actuator 5 is controlled in real time through the control device, the moving displacements of the first moving platform 2 and the second moving platform 3 are detected in real time through the sensor 6, and the displacement information detected in real time is fed back to the control device. The voltage output by the circuit to the piezoelectric actuator 5 is further adjusted in real time through the control device, so as to adjust the operation state of the piezoelectric actuator 5. In this way, a closed-loop control is formed between the sensor 6 and the piezoelectric actuator 5 to improve the positioning accuracy.

[0061] Furthermore, the positioning device achieves precise motion control at the nanometer level through the driving of the piezoelectric actuator 5, the transmission of motion by the flexible structure, the monitoring of the sensor 6, and the adjustment of the closed-loop control device. Exemplarily, the sensor 6 is a capacitive sensor. The motion information is transmitted to the control device by the ultra-precise capacitive sensor, and then the control device corrects, compensates, and controls the motion. The formation of a closed loop between the piezoelectric actuator 5 and the sensor 6 means that the displacement of the piezoelectric actuator 5 is detected in real time by the sensor 6, and the detected position signal is fed back to the control device. The control device adjusts the voltage according to the feedback signal to achieve precise positioning.

[0062] The piezoelectric actuator 5 can obtain a high displacement resolution under voltage control. At the same time, it has a high frequency response, a fast dynamic response, a large load, good mechanical static pressure characteristics, a simple structure, and little external force interference. Due to the above advantages, the piezoelectric actuator 5 is often used in precision micro-displacement positioning platforms. The displacement output by the piezoelectric actuator 5 can be amplified by the flexible structure. Furthermore, the output displacement of the piezoelectric actuator 5 can be accurately detected by the sensor 6. The sensor 6 can feed back the detected position signal to the control device, and the control device adjusts the voltage input of the piezoelectric actuator 5 according to the feedback signal to reduce errors and achieve more precise positioning.

[0063] In a possible implementation, at least one sensor 6 and at least two piezoelectric actuators 5 are located on the same center line of the base 1.

[0064] Exemplarily, setting the sensor 6 and the piezoelectric actuator 5 on the same center line of the base 1 can balance the overall weight, avoid the offset of the overall center of gravity, and enable the first moving platform 2 and the second moving platform 3 to move smoothly under the drive of the piezoelectric actuator 5, thereby improving the stability and detection accuracy during the overall movement. In one embodiment, the sensor 6 and the piezoelectric actuator 5 can be set on different axes of the base 1, and the extending directions of the axes are the same.

[0065] In a possible implementation, there are two sensors 6. One sensor 6 is arranged inside the base 1 and is used to detect the displacement of the second moving platform 3 relative to the base 1 in the first direction. The other sensor 6 is arranged inside the second moving platform 3 and is used to detect the displacement of the first moving platform 2 relative to the second moving platform 3 in the first direction.

[0066] Exemplarily, two piezoelectric actuators 5 are provided. One piezoelectric actuator 5 is disposed between the first moving platform 2 and the second moving platform 3, and the other piezoelectric actuator 5 is disposed between the second moving platform 3 and the base 1. Two sensors 6 are provided. One end of the sensor 6 disposed inside the base 1 is connected to the inner side of the base 1, and the other end is in clearance fit with the second moving platform 3. One end of the sensor 6 disposed inside the second moving platform 3 is connected to the inner side of the second moving platform 3, and the other end is in clearance fit with the first moving platform 2. When in use, when one piezoelectric actuator 5 drives the second moving platform 3 to move relative to the base 1, the sensor 6 disposed inside the base 1 detects the displacement of the second moving platform 3 in real time, and feeds back the real-time measured position information to the control device. The control device controls the magnitude of the voltage input to the piezoelectric actuator 5, thereby achieving precise positioning. Similarly, when the other piezoelectric actuator 5 drives the first moving platform 2 to move relative to the second moving platform 3, the sensor 6 disposed inside the second moving platform 3 detects the displacement of the first moving platform 2 in real time, and feeds back the real-time measured position information to the control device. The control device controls the magnitude of the voltage input to the piezoelectric actuator 5, thereby achieving precise positioning. By providing two sensors 6 to form a closed-loop control with the corresponding piezoelectric actuators 5 respectively, the detection accuracy is improved.

[0067] In a possible implementation manner, a zigzag shape is formed between the first moving platform 2 and the second moving platform 3, and a zigzag shape is formed between the second moving platform 3 and the base 1. Mounting holes are provided on the axis and / or diagonal of the base 1 and the first moving platform 2. The mounting holes of the base 1 are used to fix the base 1, and the mounting holes of the first moving platform 2 are used to fix the workpiece to be positioned.

[0068] Exemplarily, the shapes of the first moving platform 2, the second moving platform 3, and the base 1 are set to a zigzag structure to simplify the overall structure, reduce the processing difficulty in the actual production process, thereby reducing the production cost. The mounting holes of the base 1 are used to fix the base 1, and the mounting holes of the first moving platform 2 are used to fix the workpiece to be positioned. When in use, the workpiece to be positioned is fixed on the first moving platform 2 through the lock nut and the mounting holes on the first moving platform 2, preparing for the subsequent scanning and detection process.

[0069] Among them, the mounting holes on the base 1 can be arranged on the axis of the base 1 or on the diagonal of the base 1. In this embodiment, four mounting holes are provided, which are evenly and symmetrically arranged on the base 1 and penetrate through the base 1 to facilitate the stable fixation of the base 1. The mounting holes of the first moving platform 2 can be arranged on the axis of the first moving platform 2 or on the diagonal of the first moving platform 2. In this embodiment, four mounting holes are provided, which are evenly and symmetrically arranged on the first moving platform 2. The mounting holes are threaded holes and the depth is half of the thickness of the first moving platform 2. The to-be-positioned member can be fixed on the first moving platform 2 through the cooperation of the locking nut and the mounting holes.

[0070] In a possible implementation manner, the connecting structure is a flexible structure, and the flexible structure includes at least two single-degree-of-freedom flexible hinges 4, and the degree-of-freedom direction of the flexible hinge is the first direction.

[0071] Exemplarily, the flexible hinge 4 can elastically deform along the first direction under the driving action of the piezoelectric actuator 5. The elastic deformation direction of the flexible hinge 4 is consistent with the moving direction of the moving platform, so that the moving platform can move at the nanometer level under the driving of the piezoelectric actuator 5.

[0072] In a possible implementation manner, the flexible hinge 4 is arranged on the first moving platform 2 or the second moving platform 3.

[0073] Exemplarily, whether the flexible hinge 4 is arranged on the first moving platform 2 or the second moving platform 3, as long as the elastic deformation direction of the flexible hinge 4 is consistent with the moving direction of the first moving platform 2 and the second moving platform 3, the first moving platform 2 and the second moving platform 3 can be driven to move through the flexible hinge 4.

[0074] In one example, the flexible hinge 4 for connecting the first moving platform 2 and the second moving platform 3 is arranged on the first moving platform 2, and the flexible hinge 4 for connecting the second moving platform 3 and the base 1 is arranged on the second moving platform 3; in another example, the flexible hinge 4 for connecting the first moving platform 2 and the second moving platform 3 is arranged on the second moving platform 3, and the flexible hinge 4 for connecting the second moving platform 3 and the base 1 is also arranged on the second moving platform 3.

[0075] In practical applications, the flexible hinge 4 connecting the second moving platform 3 and the base 1 can also be arranged on the base 1. Specifically, the flexible hinge 4 for connecting the first moving platform 2 and the second moving platform 3 is arranged on the first moving platform 2, and the flexible hinge 4 for connecting the second moving platform 3 and the base 1 is arranged on the base 1; alternatively, the flexible hinge 4 for connecting the first moving platform 2 and the second moving platform 3 is arranged on the second moving platform 3, and the flexible hinge 4 for connecting the second moving platform 3 and the base 1 is also arranged on the base 1. That is to say, there is no restriction on the installation position of the flexible hinge 4, as long as the elastic space direction of the flexible hinge 4 is consistent with the moving direction of the first moving platform 2 and the second moving platform 3.

[0076] In a possible implementation manner, the flexible hinge 4 is symmetrically arranged along a first direction and a second direction perpendicular to the first direction within the end face of the base 1.

[0077] Exemplarily, the flexible hinges 4 between the first moving platform 2 and the second moving platform 3 and between the second moving platform 3 and the base 1 can all be set as the same type of flexible hinge 4, and the flexible hinge 4 is symmetrically arranged in the first direction and the second direction. In this way, the stress borne by all the flexible hinges 4 can be made consistent, and the stress can be evenly dispersed, which can improve the stability and balance during the overall movement.

[0078] In a possible implementation manner, a flexible hinge 4 includes at least two first flexible hinge branches and at least two second flexible hinge branches. The at least two first flexible hinge branches extend along the first direction, and the at least two second flexible hinge branches extend along the second direction. The extension length of the first flexible hinge branch is much smaller than that of the second flexible hinge branch. The first flexible hinge branch and the second flexible hinge branch are alternately connected in sequence to form a serpentine flexible hinge 4. This type of flexible hinge 4 has high stress and can improve the stability and balance during the overall movement.

[0079] Exemplarily, taking the flexible hinge 4 connecting the first moving platform 2 and the second moving platform 3 and arranged on the first moving platform 2 as an example for illustration, a flexible hinge 4 includes two first flexible hinge branches 41 and two second flexible hinge branches 42. In one example, please refer to Figure 2 , connect the first end of the lowermost first flexible hinge branch 41 to the first moving platform 2, connect the second end of the first flexible hinge branch 41 to the first end of the first second flexible hinge branch 42, connect the second end of the first second flexible hinge branch 42 to the first end of the second first flexible hinge branch 41, connect the second end of the second first flexible hinge branch 41 to the first end of the second second flexible hinge branch 42, and connect the second end of the second second flexible hinge branch 42 to the second moving platform 3, so that the overall shape of the flexible hinge 4 is arranged in a serpentine shape; in another example, please refer toFigure 3 , connect the first end of the lowermost first flexible hinge chain 41 to the second moving platform 3, connect the second end of the first first flexible hinge chain 41 to the first end of the first second flexible hinge chain 42, connect the second end of the first second flexible hinge chain 42 to the first end of the second first flexible hinge chain 41, connect the second end of the second first flexible hinge chain 41 to the first end of the second second flexible hinge chain 42, and connect the second end of the second second flexible hinge chain 42 to the first moving platform 2, so that the overall shape of the flexible hinge 4 is arranged in a snake shape. Among them, the setting of the flexible hinge 4 connecting the second moving platform 3 and the base 1 can also refer to any one or both of the above two examples.

[0080] In a possible implementation manner, a flexible hinge 4 includes three first flexible hinge chains 41 and at least three second flexible hinge chains 42. The three first flexible hinge chains 41 extend along a first direction, and at least three second flexible hinge chains 42 extend along a second direction and are arranged in parallel. The first ends of at least three second flexible hinge chains 42 are all connected to the same first flexible hinge chain 41. The second ends of the two second flexible hinge chains 42 located on the outermost side of the same column are connected to the corresponding first flexible hinge chain 41. This kind of flexible hinge 4 has high stress and can improve the stability and balance during the overall movement.

[0081] Exemplarily, taking the first moving platform 2, the second moving platform 3 and the flexible hinge 4 arranged on the first moving platform 2 as an example for illustration, a flexible hinge 4 includes three first flexible hinge chains 41 and three second flexible hinge chains 42. In one example, please refer to Figure 4 , connect the first end of the lowermost first flexible hinge chain 41 to the first moving platform 2, connect the second end of the first first flexible hinge chain 41 to the first end of the first second flexible hinge chain 42, connect the second end of the first second flexible hinge chain 42 to the first end of the second first flexible hinge chain 41, connect the second end of the second first flexible hinge chain 41 to the first end of the second second flexible hinge chain 42, connect the second end of the second second flexible hinge chain 42 to the first end of the third first flexible hinge chain 41, connect the second end of the third first flexible hinge chain 41 to the first moving platform 2, connect the first end of the third second flexible hinge chain 42 to the middle part of the second first flexible hinge chain 41, and connect the second end of the third second flexible hinge chain 42 to the first moving platform 2. In another example, please refer to Figure 5, connect the first end of the lowermost first flexible hinge chain 41 to the first moving platform 2, connect the second end of the first first flexible hinge chain 41 to the first end of the first second flexible hinge chain 42, connect the second end of the first second flexible hinge chain 42 to the first end of the second first flexible hinge chain 41, connect the second end of the second first flexible hinge chain 41 to the first end of the second second flexible hinge chain 42, connect the second end of the second second flexible hinge chain 42 to the first end of the third first flexible hinge chain 41, connect the second end of the third first flexible hinge chain 41 to the first moving platform 2, connect the first end of the third second flexible hinge chain 42 to the middle part of the second first flexible hinge chain 41, and connect the second end of the third second flexible hinge chain 42 to the first moving platform 2. Among them, the setting of the flexible hinge 4 connecting the second moving platform 3 and the base 1 can also refer to any one or both of the above two examples.

[0082] Exemplarily, taking the first moving platform 2 and the second moving platform 3 and the flexible hinge 4 arranged on the first moving platform 2 as an example for illustration, a flexible hinge 4 includes three first flexible hinge chains 41 and four second flexible hinge chains 42. In one embodiment, please refer to Figure 6 , connect the first end of the lowermost first flexible hinge chain 41 to the first moving platform 2, connect the second end of the first first flexible hinge chain 41 to the first end of the first second flexible hinge chain 42, connect the second end of the first second flexible hinge chain 42 to the first end of the second first flexible hinge chain 41, connect the second end of the second first flexible hinge chain 41 to the first end of the second second flexible hinge chain 42, connect the second end of the second second flexible hinge chain 42 to the first end of the third first flexible hinge chain 41, connect the second end of the third first flexible hinge chain 41 to the first moving platform 2, connect the first ends of the third second flexible hinge chain 42 and the fourth second flexible hinge chain 42 to the second first flexible hinge chain 41, and connect the second ends of the third second flexible hinge chain 42 and the fourth second flexible hinge chain 42 to the second moving platform 3. In another embodiment, please refer to Figure 7, connect the first end of the lowermost first flexible hinge chain 41 to the second moving platform 3, connect the second end of the first first flexible hinge chain 41 to the first end of the first second flexible hinge chain 42, connect the second end of the first second flexible hinge chain 42 to the first end of the second first flexible hinge chain 41, connect the second end of the second first flexible hinge chain 41 to the first end of the second second flexible hinge chain 42, connect the second end of the second second flexible hinge chain 42 to the first end of the third first flexible hinge chain 41, connect the second end of the third first flexible hinge chain 41 to the second moving platform 3, and connect the first ends of the third second flexible hinge chain 42 and the fourth second flexible hinge chain 42 to the second first flexible hinge chain 41. Connect the second ends of the third second flexible hinge chain 42 and the fourth second flexible hinge chain 42 to the first moving platform 2. That is to say, when there is no limit to the length of the first flexible hinge chain 41, no matter how many second flexible hinge chains 42 are set, the connection between the first moving platform 2 and the second moving platform 3 can be realized by using three first flexible hinge chains 41. Among them, the setting of the flexible hinge 4 connecting the second moving platform 3 to the base 1 can also refer to any one or both of the above two embodiments.

[0083] In a possible implementation manner, at least three second flexible hinge chains 42 are arranged at equal intervals along the first direction.

[0084] Exemplarily, arranging multiple second flexible hinge chains 42 at equal intervals in the first direction can improve the stability of the movement of the first moving platform 2 and the second moving platform 3.

[0085] In a possible implementation manner, the cross-sections of the first flexible hinge chain 41 and the second flexible hinge chain 42 are rectangular, with a simple structure, which is convenient for processing and production.

[0086] In a possible implementation manner, the flexible hinge 4 includes a flexible hinge body. The cross-section of the flexible hinge body is rectangular. There are two groups of circular perforations arranged at intervals along the first direction on the flexible hinge body. Each group of circular perforations includes two circular holes arranged symmetrically with respect to the first direction as the axis of symmetry. The structure is simple and the shape is regular, ensuring high-precision movement. Compared with the traditional rigid hinge, two groups of circular perforations are provided on the flexible hinge body, which enhances the fatigue resistance of the flexible hinge body, and has a simple structure and low processing cost. For this kind of flexible hinge body, the two circular holes in each group of circular perforations can be connected or not, and there is no limitation on this, and it can be set according to actual needs.

[0087] The flexible hinge 4 has the advantages of no clearance, no friction, no noise, small space size, easy control, stable operation, etc. Therefore, the flexible hinge 4 has become a new type of hinge form widely used in many precision machinery such as aerospace, robotics, optics, and bioengineering, and is an important component in precision machinery.

[0088] Based on the above embodiments, please refer to Figure 8 , the present application provides a scanning device, including a scanning lens 7 and the positioning device described in any of the above embodiments. The scanning lens 7 is detachably arranged on the above-mentioned positioning device. The scanning lens 7 is located in the middle of the first moving platform 2 and can drive the scanning lens 7 to perform nano-scale scanning and positioning.

[0089] When using this device, the piezoelectric actuator 5 of the positioning device drives the first moving platform 2 and the second moving platform 3 to move, thereby driving the scanning lens 7 to move synchronously. The flexible structure of the positioning device amplifies the displacement output by the piezoelectric actuator 5, and the sensor 6 of the positioning device real-time detects the moving displacements of the first moving platform 2 and the second moving platform 3, and feeds back the real-time detected displacement information to the control device of the positioning device. The control device further adjusts the voltage output by the circuit to the piezoelectric actuator 5 in real time, thereby adjusting the operating state of the piezoelectric actuator 5. In this way, a closed-loop control is formed between the sensor 6 and the piezoelectric actuator 5 to improve the accuracy of the scanning of the scanning lens 7.

[0090] Exemplarily, the scanning lens 7 can be installed and fixed on the first moving platform 2 of the positioning device to drive the scanning lens 7 to perform nano-scale scanning and positioning, so as to achieve large-stroke dynamic response and high-bandwidth dynamic response during the movement of the scanning lens 7. This scanning device can be used for optical measurement, detection, and optical processing.

[0091] Based on the above embodiments, please refer to Figure 9 , the present application provides a scanning probe device, including a probe 8 and the positioning device described in any of the above embodiments. The probe 8 is detachably arranged on the above-mentioned positioning device through an adapter 9. The probe 8 is located in the middle of the first moving platform 2 and can drive the probe 8 to perform nano-scale scanning and positioning.

[0092] When using the device, the piezoelectric actuator 5 of the positioning device drives the first moving platform 2 and the second moving platform 3 to move, thereby driving the probe 8 to move synchronously. The flexible structure of the positioning device amplifies the displacement output by the piezoelectric actuator 5, and the sensor 6 of the positioning device real-time detects the moving displacements of the first moving platform 2 and the second moving platform 3, and feeds back the real-time detected displacement information to the control device of the positioning device. The control device further adjusts the voltage output by the circuit to the piezoelectric actuator 5 in real time, thereby adjusting the operating state of the piezoelectric actuator 5. In this way, a closed-loop control is formed between the sensor 6 and the piezoelectric actuator 5 to improve the accuracy of the probe 8 scanning.

[0093] Exemplarily, the probe 8 can be fixed to the first moving platform 2 through the adapter 9 to drive the probe 8 for nano-scale scanning and positioning, and large-stroke dynamic response and high-bandwidth dynamic response during the movement of the probe 8 can be achieved. This scanning probe 8 device can be used for measurement, detection, and optical processing based on the principle of the probe 8.

[0094] In the above embodiments, the purpose, technical solutions, and advantages of the present invention have been further described in detail. It should be understood that the above are only embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A positioning device, characterized in that, Comprising: A base, the base is connected with a first moving platform and a second moving platform which are nested, the first moving platform is located inside the second moving platform, and the second moving platform is connected to the base and the first moving platform through connection structures respectively; At least two piezoelectric drivers, wherein at least one of the piezoelectric drivers is used to drive the second moving platform to move relative to the base along a first direction, and at least one of the piezoelectric drivers is used to drive the first moving platform to move relative to the second moving platform along the first direction.

2. The positioning device according to claim 1, wherein The at least two piezoelectric drivers are located on the same center line of the base.

3. The positioning device according to claim 1, characterized in that, It further comprises at least one sensor for detecting the displacement of the first moving platform and the second moving platform moving along the first direction.

4. The positioning device according to claim 3, wherein The at least one sensor and the at least two piezoelectric drivers are located on the same center line of the base.

5. The positioning device according to any one of claims 3 or 4, characterized in that, There are two sensors. One sensor is arranged inside the base and is used to detect the displacement of the second moving platform moving relative to the base along the first direction, and the other sensor is arranged inside the second moving platform and is used to detect the displacement of the first moving platform moving relative to the second moving platform along the first direction.

6. The positioning device according to claim 4, characterized in that, It further comprises a control device, the control device is respectively connected to the sensor and the piezoelectric driver, and the control device is used to convert the signal from the sensor into a control signal to control the circuit to output voltage to the piezoelectric driver.

7. The positioning device according to claim 1, characterized in that, A zigzag arrangement is formed between the first moving platform and the second moving platform, and a zigzag arrangement is formed between the second moving platform and the base. Mounting holes are provided on the axis and / or diagonal of the base and the first moving platform. The mounting holes of the base are used to fix the base, and the mounting holes of the first moving platform are used to fix the piece to be positioned.

8. The positioning device according to claim 1, characterized in that The connection structure is a flexible structure, the flexible structure includes at least two single-degree-of-freedom flexible hinges, and the degree-of-freedom direction of the flexible hinge is the first direction.

9. The positioning device according to claim 8, characterized in that, The flexible hinge is arranged on the first moving platform or the second moving platform.

10. The positioning device according to claim 9, characterized in that, The flexible hinge is symmetrically arranged along the first direction and a second direction perpendicular to the first direction within the end face of the base.

11. The positioning device according to claim 10, wherein One flexible hinge includes at least two first flexible hinge branches and at least two second flexible hinge branches. At least two of the first flexible hinge branches extend along the first direction, and at least two of the second flexible hinge branches extend along the second direction. The extension length of the first flexible hinge branch is much smaller than the extension length of the second flexible hinge branch, and the first flexible hinge branch and the second flexible hinge branch are alternately connected in sequence.

12. The positioning device according to claim 11, characterized in that, One of the flexible hinges includes three first flexible hinge branches and at least three second flexible hinge branches. The three first flexible hinge branches extend along the first direction, and at least three second flexible hinge branches extend along the second direction and are arranged in parallel. The first ends of at least three second flexible hinge branches are all connected to the same first flexible hinge branch, and the second ends of the two second flexible hinge branches located on the outermost side of the same column are connected to the corresponding first flexible hinge branches.

13. The positioning device according to claim 12, wherein At least three second flexible hinge branches are arranged at equal intervals along the first direction.

14. A scanning device, characterized in that, Comprising: A scanning lens, the scanning lens is detachably arranged on the positioning device according to any one of claims 1-13, and the scanning lens is located in the middle of the first moving platform.

15. A scanning probe device, characterized in that, Comprising: A probe, the probe is detachably arranged on the positioning device according to any one of claims 1-13 through an adapter, and the probe is located in the middle of the first moving platform.

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