Bimorph tube driven inertial motor, control method thereof and scanning probe microscope

Abstract

This invention discloses a dual-piezoelectric tube driven inertial motor and its control method, along with a scanning probe microscope, relating to the field of piezoelectric tube technology. The invention includes a base, a first piezoelectric tube, a second piezoelectric tube, and a U-shaped sliding body. The first and second piezoelectric tubes are parallel to each other along their axes, with one end fixed to the base and the other end free. The two parallel arms of the U-shaped sliding body, referred to as the left and right sliding rods, are elastically connected via a junction at the bottom of the U-shaped sliding body. The left and right sliding rods are coaxially inserted into the inner walls of the first and second piezoelectric tubes, respectively. This invention not only ensures that the two sliding rods consistently and stably abut against the inner cavities of their respective piezoelectric tubes, guaranteeing effective transmission of driving force, but also improves the overall mechanism's motion accuracy, load-bearing capacity, and anti-interference capability through the coordinated and alternating operation of the dual-drive piezoelectric tubes, laying a structural foundation for achieving high-precision and high-stability stepping motion.

Description

Technical Field

[0001] This invention relates to the field of piezoelectric technology, specifically to a dual-piezoelectric driven inertial motor and its control method, and a scanning probe microscope. Background Technology

[0002] A piezoelectric inertial motor is a precision micro / nano positioning device based on the inverse piezoelectric effect and inertial drive principle. Its core structure is a thin-walled cylinder made of piezoelectric ceramic (generally called a piezoelectric tube). By applying a specific voltage, the piezoelectric tube undergoes minute deformation, and the asymmetry of friction between the drive end and the moving slider is cleverly utilized to achieve directional stepping motion. Its working principle is as follows: In one drive cycle, the piezoelectric tube is first slowly extended by a gradual change in voltage, at which point the slider moves along with it due to static friction. Subsequently, the voltage is rapidly reset, the piezoelectric tube rapidly contracts, and the slider, due to inertia and reduced dynamic friction, stops at the new position. This cycle repeats, and the slider accumulates macroscopic displacement in nanometer-scale steps.

[0003] Piezoelectric inertial motors are widely used in cutting-edge fields requiring extreme precision and stability. In scientific instruments, they are the core component for achieving nanoscale scanning and positioning of samples or probes in scanning probe microscopes (such as atomic force microscopes).

[0004] A search revealed that patent application CN117997161A discloses a piezoelectric tube self-guided inertial piezoelectric motor and a scanning probe microscope made therefrom. The motor includes a polygonal slider, a base, a spring plate, and a circular piezoelectric tube. One end of the circular piezoelectric tube is fixed to the base, and the other end is a free end. The polygonal slider is coaxially inserted into the circular piezoelectric tube. The spring plate applies a normal force perpendicular to the deformation direction of the circular piezoelectric tube, which elastically presses the polygonal slider against the inner wall of the circular piezoelectric tube. The polygonal slider and the circular piezoelectric tube can slide relative to each other.

[0005] The working principle of the aforementioned inertial piezoelectric motor is as described above: During operation, voltage is applied simultaneously and in the same direction to each piezoelectric element to generate a slow thrust. The slider is pushed upward a certain distance by friction. Then, a reverse voltage is suddenly applied, causing the piezoelectric scanning tube to deform in the opposite direction. However, due to inertia, the slider is subjected to inertial force. When the inertial force is greater than the frictional force of the piezoelectric scanning tube on the slider, the slider can slide relative to the piezoelectric scanning tube, thus completing the stepping in the Z direction.

[0006] The above design has significant technical limitations: its drive relies on a single piezoelectric tube, providing only a single degree of freedom (Z-direction) for stepping motion. When a constant voltage excitation is applied to this single piezoelectric tube, the displacement (or step size) generated in each step is essentially fixed, so the final displacement can only be obtained by accumulating integer multiples of this fixed step size. Furthermore, because the displacement (step size) generated in each step is currently quite large, this motion method makes it difficult for the motor to stop precisely at the designated displacement, easily leading to reduced positioning accuracy due to "step overshoot." Especially when this motor is used to drive the probe of a scanning probe microscope, this overshoot phenomenon may cause the probe to accidentally collide with the sample (i.e., impact pin), damaging the instrument or the sample. Summary of the Invention

[0007] The purpose of this invention is to solve the problems in the prior art by proposing a dual piezoelectric tube driven inertial motor. By coordinating and alternating the work of the two driving piezoelectric tubes, the motion accuracy and anti-interference of the overall mechanism are improved, and the risk of pin collision is avoided.

[0008] To address the above problems, the present invention provides the following technical solution: A dual-piezoelectric tube driven inertial motor includes: a base; and further includes: a first piezoelectric tube, a second piezoelectric tube, and a U-shaped sliding body; the first piezoelectric tube and the second piezoelectric tube are parallel to each other along their axes, with one end of each fixed to the base and the other end being a free end; the two parallel arms of the U-shaped sliding body are respectively called the left sliding rod and the right sliding rod, which are elastically connected through a transition part at the bottom of the U-shaped sliding body; the left sliding rod and the right sliding rod are respectively inserted parallel and coaxially into the inner walls of the first piezoelectric tube and the second piezoelectric tube, forming a structure in which the left sliding rod and the right sliding rod are elastically pressed against the inner walls of the first piezoelectric tube and the second piezoelectric tube, respectively.

[0009] As a further aspect of the present invention, it also includes two sleeves, which are coaxially fixed to the inner walls of the free ends of the first piezoelectric tube and the second piezoelectric tube, respectively. The left slide rod and the right slide rod are coaxially inserted into the inner walls of the two sleeves, forming a structure in which the left slide rod and the right slide rod are elastically pressed against the inner walls of the two sleeves.

[0010] As a further aspect of the present invention: the left slide rod and the right slide rod are respectively provided with side edges along their length direction, and the side edges are linearly in contact with the sleeves of the inner walls of the first piezoelectric tube and the second piezoelectric tube.

[0011] As a further aspect of the present invention: the placement block is positioned at the top of the left and right sliding rods.

[0012] As a further aspect of the present invention: the adapter has a slit, and the horizontal opposing elastic force generated by the slit elastically presses the left and right slide rods against the inner walls of the first and second piezoelectric tubes respectively.

[0013] This invention also proposes a control method for a dual-piezoelectric driven inertial motor, which controls the first and second piezoelectric transistors respectively with signals in the following timing sequence to complete one cycle of stepping: (1) Apply a piezoelectric elongation signal to the first piezoelectric tube, the elongation generating an inertial force on the left slide bar that is less than the maximum static friction force it experiences; (2) Apply a piezoelectric contraction signal to the first piezoelectric tube, the inertial force generated by the contraction on the left slide rod is greater than the maximum static friction force it experiences; (3) Apply a piezoelectric elongation signal to the second piezoelectric tube, the inertial force generated by the elongation on the right slide rod is less than the maximum static friction force it experiences; (4) Apply a piezoelectric contraction signal to the second piezoelectric tube, the inertial force generated by the contraction on the right slide rod is greater than the maximum static friction force it experiences.

[0014] The present invention also proposes a scanning probe microscope made of the above-mentioned dual piezoelectric tube driven inertial motor, comprising: a first support, a second support, a third support, and a fourth support; the first support is fixed to the top of the left slide bar, the second support is fixed to the top of the right slide bar, the third support and the fourth support are respectively disposed on the base, with the third support located above the first support and the fourth support located above the second support; both the first and second piezoelectric tubes are XYZ piezoelectric scanning tubes, and a probe is disposed on both the first and second supports.

[0015] This invention also proposes a control method for a scanning probe microscope, which controls the first piezoelectric tube and the second piezoelectric tube respectively using the following timing signals: (a) When a piezoelectric elongation signal is applied to the first piezoelectric tube, the left slider moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (c). If no tunneling current is detected, this step is repeated until the total displacement of the left slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b) An inertial swing signal is applied to the first piezoelectric tube. Under the action of this signal, the displacement of the left slider is: , Satisfy: (1) and Same direction, (2) | |<| |; (c) Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (f). If no tunneling current is detected, this step is repeated until the total displacement of the right slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d) An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e) Return to step (a) and repeat the process to achieve step-by-step displacement approximation; (f) After the coarse approximation ends, the first piezoelectric tube and the second piezoelectric tube perform scanning imaging respectively.

[0016] The present invention also proposes a scanning probe microscope made of the above-mentioned dual piezoelectric tube driven inertial motor, comprising: a fifth support and a sixth support; the fifth support is fixed at the center of the object block, the sixth support is fixed on the base, the sixth support is located above the fifth support, the first piezoelectric tube and the second piezoelectric tube are both XYZ piezoelectric scanning tubes, and a second probe is provided on the fifth support.

[0017] This invention also proposes a control method for a scanning probe microscope, which controls the first piezoelectric tube and the second piezoelectric tube respectively using the following timing signals: (a') A piezoelectric elongation signal is applied to the first piezoelectric tube, and the left slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the left slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b') An inertial swing signal is applied to the first piezoelectric tube, which generates a displacement of the left slider as follows: , Satisfy: (1) and Same direction, (2) | |<| |; (c') Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the right slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d') An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e') Return to step (a') and repeat the process to achieve step-by-step displacement approximation.

[0018] This invention also proposes a scanning method for a scanning probe microscope with a dual piezoelectric tube driven inertial motor, comprising the following steps: Step 1: Apply a voltage in the same direction to all the piezoelectric blocks on the first piezoelectric tube, causing the first piezoelectric tube and the slide bar to step upward to the target position. At this time, the slide bar will lift one end of the object block upward, causing the object block to tilt, so that the second probe deflects toward the second piezoelectric tube, thus realizing scanning in this direction. Step 2: Reset the slider and the block from Step 1; Step 3: Apply the same voltage to all the piezoelectric blocks on the second piezoelectric tube, causing the piezoelectric tube and the slide bar to move upward in the same direction. At this time, the slide bar will lift the other end of the block upward, causing the block to tilt, so that the second probe deflects toward the first piezoelectric tube, thus achieving scanning in that direction. Step 4: Reset the slider and the block from Step 3 to complete the scan.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. By setting two sets of parallel piezoelectric tubes and sliding rods, and connecting the two sliding rods with an adapter to form a sliding whole with a tendency to move closer or further apart, a symmetrical driving mechanism is constructed. This design not only ensures that the two sliding rods are always stably in contact with the inner cavity of the corresponding piezoelectric tubes, ensuring effective transmission of driving force, but also improves the motion accuracy, load-bearing capacity, and anti-interference ability of the overall mechanism through the coordinated and alternating work of the two driving piezoelectric tubes, laying a structural foundation for achieving high-precision and high-stability stepping motion in the future.

[0020] 2. By setting at least one set of side ridges that abut against the inner cavity of the piezoelectric tube along the length of the slide rod, the surface contact between the slide rod and the tube wall is optimized into a linear or near-linear contact. This design greatly reduces the sliding friction area and effectively reduces frictional resistance, making the slide rod move more smoothly and respond more sensitively in the piezoelectric tube, thereby improving driving efficiency and motion resolution.

[0021] 3. By defining the adapter as a block connecting the ends of the two slide rods, forming a U-shaped whole, the relative position between the two slide rods is firmly fixed, which can effectively resist external disturbances and ensure that the two slide rods always move as a coordinated whole during the driving process. This avoids the asynchronous and inconsistent stepping movements of the two slide rods due to the different driving forces generated by the two piezoelectric tubes over time.

[0022] 4. By limiting the two sliding rods in the U-shaped whole to be parallel and opening a slit in the middle of the block, the introduction of the slit gives the U-shaped whole a specific elasticity, which can actively provide a continuous and stable inward pre-tightening force for the two sliding rods. This pre-tightening force automatically ensures the necessary contact force between the sliding rod and the inner cavity of the piezoelectric tube, without the need to apply additional complex external pre-tightening devices, simplifying assembly and ensuring performance consistency.

[0023] 5. The inertial motor control method of this application sequentially applies the same-direction voltage to two piezoelectric tubes to drive the slide bar to step, and then suddenly changes to the opposite voltage to reset it while the slide bar remains due to inertia. Finally, the two slide bars are lifted with equal displacement. This decomposes one displacement into two more easily controlled micro-steps, reducing the amount of displacement driven in a single drive, thereby improving the resolution and accuracy of displacement control in principle.

[0024] 6. By designing a block with an inverted V-shaped inclined surface to support the probe, and using the two inclined surfaces to abut the tops of the two sliding rods respectively, a two-point support structure is obtained. This structure allows the probe's lifting and lowering motion to be directly driven by the precision stepping of the double sliding rods. It not only inherits the high precision advantage of the motor itself, but also the inverted V-shaped inclined surface layout can effectively convert the vertical contact force of the sliding rods into a stable clamping force on the block, improving the rigidity and anti-lateral interference ability of the probe during the scanning process. Attached Figure Description

[0025] The invention will now be further described with reference to the accompanying drawings.

[0026] Figure 1 This is a three-dimensional structural schematic diagram of the inertial motor of the present invention; Figure 2 This is a top view schematic diagram of the inertial motor of the present invention; Figure 3 This is a front view structural schematic diagram of the inertial motor of the present invention; Figure 4 yes Figure 1A 3D structural diagram showing the removal of the item block in the current state; Figure 5 This is a schematic diagram of the U-shaped integral three-dimensional structure in the inertial motor of the present invention; Figure 6 This is a schematic diagram of the three-dimensional structure of the two sets of piezoelectric tubes and the base in the inertial motor of the present invention. Figure 1 ; Figure 7 This is a schematic diagram of the frontal structure of the microscope of the present invention. Figure 1 ; Figure 8 This is a schematic diagram of the frontal structure of the microscope of the present invention. Figure 2 ; Figure 9 This is a three-dimensional structural diagram of the piezoelectric tube and sleeve of the present invention. Figure 10 This is a schematic diagram of the three-dimensional structure of the two sets of piezoelectric tubes and the base in the inertial motor of the present invention. Figure 2 .

[0027] In the diagram: 1. Base; 2. Piezoelectric tube; 201. Piezoelectric block; 201a. First quadrant piezoelectric block; 201b. Second quadrant piezoelectric block; 201c. Third quadrant piezoelectric block; 201d. Fourth quadrant piezoelectric block; 202. Groove; 3. Sliding rod; 4. Adapter; 401. Slit; 5. Side edge; 6. Probe II; 7. Placement block; 701. Inclined surface; 8. Sample holder; 9. First holder; 10. Second holder; 11. Third holder; 12. Fourth holder; 13. Probe I; 14. Sleeve. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1: like Figures 1-6 As shown, a dual-piezoelectric-driven inertial motor includes a base 1 and two sets of piezoelectric tubes 2. The two sets of piezoelectric tubes 2 are arranged side by side, with one end fixedly mounted on the base 1, and the other end forming a free end. This state is determined by... Figure 6 When representing this, it is shown that the bottom end of the piezoelectric tube 2 is fixedly installed on the base 1, and the top end of the piezoelectric tube 2 forms a free end.

[0030] In each view, the piezoelectric tube 2 located on the left is defined as the first piezoelectric tube, and the piezoelectric tube 2 located on the right is defined as the second piezoelectric tube.

[0031] The inertial motor of the present invention also includes a slide bar 3. Based on the two sets of piezoelectric tubes 2, two sets of slide bars 3 are also correspondingly provided. The bottom ends of the two sets of slide bars 3 are connected by an adapter 4, so that the three together constitute a sliding assembly. This sliding assembly is used to give the two slide bars 3 a tendency to move closer or further apart.

[0032] When the two sliding rods 3 of the sliding assembly pass through the two piezoelectric tubes 2 from bottom to top, if the sliding assembly causes the two sliding rods 3 to move closer to each other, then the two sliding rods 3 will abut against the adjacent inner cavities of the two piezoelectric tubes 2; if the sliding assembly causes the two sliding rods 3 to move further apart from each other, then the two sliding rods 3 will abut against the distancing inner cavities of the two piezoelectric tubes 2. In either case, the sliding assembly can be flexibly installed within the two piezoelectric tubes 2.

[0033] This article uses the example of two sliders 3 having a tendency to move closer to each other to illustrate the point: To create this motion trend, the transition part 4 is set as a block, with both ends of the block connected to the ends of the two sets of sliding rods 3, so that the sliding assembly forms a U-shape or a U-shaped sliding body. Taking the U-shaped sliding assembly as an example, in Figure 3 and Figure 8 From the shown perspective, the two parallel arms of the U-shaped sliding body are referred to as the left sliding rod and the right sliding rod, respectively. The left and right sliding rods are inserted parallel and coaxially into the inner walls of the first and second piezoelectric tubes, forming a structure in which the left and right sliding rods are elastically pressed against the inner walls of the first and second piezoelectric tubes, respectively. Then, a slit 401 of a certain depth is opened in the middle of the block along the length of the sliding rod 3. With the presence of this slit 401, the two sliding rods 3 tend to move closer to each other.

[0034] Preferably, the U-shape is integrally formed and its material is any one of beryllium copper alloy, titanium alloy, or NiTi alloy.

[0035] To achieve contact between the slide rod 3 and the inner cavity of the piezoelectric tube 2, the present invention provides at least one set of side ridges 5 along the length of the slide rod 3, which achieves contact with the inner cavity of the piezoelectric tube 2. Preferably, the side ridges 5 are in linear contact with the inner cavity of the piezoelectric tube 2.

[0036] Furthermore, such as Figure 9 As shown, this application also includes two sleeves 14, which are coaxially fixed to the inner walls of the free ends of the two sets of piezoelectric tubes 2. Two sets of sliding rods 3 are coaxially inserted into the inner walls of the two sleeves 14, and the two sets of sliding rods 3 are elastically pressed against the inner walls of the two sleeves 14. Meanwhile, regarding the insertion of the sliding rods 3 into the piezoelectric tubes 2, the sliding rods 3 can also be configured as a rectangle, relying on their four sides to achieve linear contact with the inner walls of the piezoelectric tubes 2. Of course, when sleeves 14 are provided, regardless of the sliding rod configuration... Figure 4The shape shown is still Figure 9 As shown in the figure, the sliding rods are all in linear contact with the sleeve 14 inside the piezoelectric tube 2.

[0037] It should be noted that the side edge 5 of the slide rod 3 has a certain height (or length), and its contact with the inner wall of the piezoelectric tube 2 is a line contact with a certain height. Therefore, the axial expansion and contraction of the piezoelectric tube 2 is provided by all the contact points of the piezoelectric tube 2 along this line. The axial expansion and contraction force in the middle or lower part of the inner wall of the piezoelectric tube 2 is not as strong as that near the top free end. After adding the sleeve 14, the force can be concentrated only at the top free end of the piezoelectric tube 2, which is exactly where the movement and output force of the piezoelectric tube 2 are the strongest. Therefore, it can achieve the most powerful and rapid driving effect for the slide rod 3.

[0038] The piezoelectric tube 2 has the characteristic of elongating when a voltage is applied in the same direction and contracting when a voltage is applied in the opposite direction. Specifically, the piezoelectric tube 2 is formed by a circumferential array of four sets of piezoelectric blocks 201, each of which is independently controlled. Figure 6 In the vertical layout shown, each group of piezoelectric blocks 201 extends upward when subjected to the same voltage, and contracts downward when subjected to the opposite voltage.

[0039] Under the aforementioned characteristics of piezoelectric block 201, such as Figure 1 As shown, the method of using the inertial motor in this application is as follows: Step 1: Apply a voltage in the same direction to the four sets of piezoelectric blocks 201 on any set of piezoelectric tubes (e.g., the left one) 2. This will cause the top of the piezoelectric tube 2 to extend upward. Since the slide rod 3 is elastically installed in the inner cavity of the piezoelectric tube 2, the friction between the slide rod 3 and the inner cavity of the piezoelectric tube 2 can drive the left slide rod 3 to move upward. Since the two slide rods 3 and the adapter 4 together form a sliding whole, during the upward stepping process of the left slide rod 3, the right slide rod 3 still stably contacts the inner cavity of the right piezoelectric tube 2, and the sliding whole will be in a deflected state.

[0040] Step 2: When the left slider 3 moves upward to the target position, the same-direction voltage is suddenly changed to the reverse voltage. At this time, the top of the left piezoelectric tube 2 will retract downward. However, due to the large inertia of the slider 3, it will remain at the target position. Then, the control of the left piezoelectric tube 2 ends, thus completing the upward movement of the left slider 3.

[0041] Step 3: Apply the same directional voltage as in Step 1 to the four sets of piezoelectric blocks 201 on the other set of piezoelectric tubes (right side) 2 until the slider 3 in the right piezoelectric tube 2 moves upward to be flush with the slider 3 on the left side; during this process, the overall offset state of the sliding gradually disappears and returns to the correct position.

[0042] Step 4: Change the voltage from the same direction to the opposite direction, causing the top of the right piezoelectric tube 2 to retract downwards. During this process, the right slider 3 remains stationary. Remove the voltage to the piezoelectric tube 2, and then the two sliders 3 will move upwards in equal steps.

[0043] This invention utilizes a sequential upward stepping mechanism for the two sliding rods 3. Specifically, when a block 7 is positioned at the top of each sliding rod 3, after one sliding rod 3 completes its upward step, one end of the block 7 is lifted, resulting in an overall tilted position. After the other sliding rod 3 completes the same upward step, the other end of the block 7 is simultaneously lifted, returning the entire structure to its upright position, thus completing the final upward step. Compared to the prior art method of directly driving the slider upward using a single piezoelectric tube, the upward stepping of the entire sliding mechanism in this invention is achieved by the stepping of two sets of piezoelectric tubes 2, offering at least the following advantages: (1) The stepping process is divided into two sub-steps. Each step only requires controlling the micro-displacement of a single slider 3, which improves the motion accuracy, reduces the single driving force and displacement fluctuation, and has higher displacement resolution.

[0044] (2) During the sliding process, one side of the slide rod 3 always maintains contact with the piezoelectric tube 2 for support, which avoids the whole being suspended or unbalanced, and the movement is more stable.

[0045] (3) The timing, voltage amplitude and action time of the stepping on both sides can be adjusted as needed to achieve asymmetrical or variable speed motion to adapt to different working conditions.

[0046] (4) The load is borne by the two sliding rods 3, which disperses the single-point friction and stress, which is beneficial to extending the service life of the piezoelectric tube 2.

[0047] Example 2: like Figure 7 As shown, based on Embodiment 1, this application proposes a scanning probe microscope, including a sample holder 8 disposed on a base 1. The aforementioned placement block 7 is improved by: a probe 6 is disposed on its top, with inclined surfaces 701 at both ends, to... Figure 3 From the frontal view, the two inclined surfaces 701 present an inverted V-shape layout, and the object block 7 relies on the two inclined surfaces 701 to abut the tops of the two sliding rods 3 respectively; at this time, the sample holder 8 is located above the probe 6.

[0048] For example Figure 7 As shown, a fifth support is fixedly installed at the center of the top of the placement block 7, and the probe 2 6 is installed at the top of the fifth support; at the same time, the sample support 8 can be defined as the sixth support, and the piezoelectric tube 2 is an XYZ piezoelectric scanning tube.

[0049] Specifically, the piezoelectric tube 2 is formed by a circumferential array of four sets of piezoelectric blocks 201, with a groove 202 formed between any two adjacent piezoelectric blocks 201. In this embodiment, the arrangement of the two piezoelectric tubes 2 can be... Figure 6 The two piezoelectric tubes 2 are arranged symmetrically, and the line connecting the axes of the two piezoelectric tubes 2 passes through the two sets of grooves 202 on each piezoelectric tube 2 in sequence.

[0050] To achieve sample scanning, this embodiment defines the following: grooves 202 in the two piezoelectric tubes 2 that are close to each other are defined as adjacent grooves, and grooves 202 that are far apart are defined as disjoint grooves. Simultaneously, the side edges 5 on the slide rod 3 are set into three groups, and these three groups of side edges 5 are arranged in a T-shape. This arrangement can be achieved by… Figure 5 To illustrate; for a single set of slide bars 3, only one set of side edges 5 is located on the line connecting the two adjacent slots.

[0051] For example Figure 6 As shown, taking the left piezoelectric tube 2 as an example, a planar xy coordinate system is established at its top. The x-coordinate is established along the line connecting the axes of the two piezoelectric tubes 2, and the y-coordinate is established perpendicular to the x-coordinate. The four groups of piezoelectric blocks 201 can be divided into piezoelectric blocks 201a (first quadrant), 201b (second quadrant), 201c (third quadrant), and 201d (fourth quadrant). Correspondingly, the same coordinate system is also established on the right piezoelectric tube 2, with each group of piezoelectric blocks 201 classified in the same way. To avoid confusion, this system is not shown in the figure.

[0052] When the item to be scanned is placed on the sample holder 8 and an x-axis scan is required: (1) +x scan: No voltage is applied to the right piezoelectric tube 2, and a voltage in the same direction is applied to the second quadrant piezoelectric block 201b and the third quadrant piezoelectric block 201c in the left piezoelectric tube 2, while a voltage in the opposite direction is applied to the first quadrant piezoelectric block 201a and the fourth quadrant piezoelectric block 201d. At this time, the top of the left piezoelectric tube 2 will bend in the +x direction; at the same time, since the slider 3 in the left piezoelectric tube 2 has a tendency to move closer to the right piezoelectric tube 2, it will move along the +x direction, that is, the left slider 3 will move in the +x direction. Figure 3 If we represent it this way, the movement of the left slider 3 in the +x direction can be represented as moving to the right. Since the top of the left slider 3 is in contact with the inclined surface 701 of the block 7, when the top of the left slider 3 moves to the right, the left end of the block 7 will be pushed up and tilted. That is, the probe 6 gradually tilts within the +x range to achieve the +x scan.

[0053] (2) -x scan: No voltage is applied to the left piezoelectric tube 2, and a voltage in the same direction is applied to the first quadrant piezoelectric block 201a and the fourth quadrant piezoelectric block 201d in the right piezoelectric tube 2, while a voltage in the opposite direction is applied to the second quadrant piezoelectric block 201b and the third quadrant piezoelectric block 201c. At this time, the top of the right piezoelectric tube 2 will bend in the -x direction; at the same time, since the slider 3 in the right piezoelectric tube 2 has a tendency to move closer to the left piezoelectric tube 2, it will move along the -x direction, that is, the right slider 3 will move in the -x direction. Figure 3 If we represent it this way, the movement of the right slider 3 in the -x direction can be represented as moving to the left. Since the top of the right slider 3 is in contact with the inclined surface 701 of the block 7, when the top of the right slider 3 moves to the left, the right end of the block 7 will be pushed up and tilted. That is, the probe 6 gradually tilts within the -x range to achieve the -x scan.

[0054] When a y-axis scan is required: (1) +y scan: Simultaneously apply the same voltage to the third quadrant piezoelectric block 201c and the fourth quadrant piezoelectric block 201d on the left piezoelectric tube 2 and the right piezoelectric tube 2, and simultaneously apply the opposite voltage to the first quadrant piezoelectric block 201a and the second quadrant piezoelectric block 201b on the left piezoelectric tube 2 and the right piezoelectric tube 2. At this time, the top of the left piezoelectric tube 2 and the right piezoelectric tube 2 will bend in the +y direction. Due to the presence of the side edge 5, the slide bar 3 will bend in the +y direction, which will cause the entire object block 7 to shift. That is, the probe 2 6 will gradually tilt within the +y range to achieve the +y scan.

[0055] (2) -y scan: Simultaneously apply the same voltage to the first quadrant piezoelectric block 201a and the second quadrant piezoelectric block 201b on the left piezoelectric tube 2 and the right piezoelectric tube 2, and simultaneously apply the opposite voltage to the third quadrant piezoelectric block 201c and the fourth quadrant piezoelectric block 201d on the left piezoelectric tube 2 and the right piezoelectric tube 2. At this time, the top of the left piezoelectric tube 2 and the right piezoelectric tube 2 will bend in the -y direction. Due to the presence of the side edge 5, the slide bar 3 will bend in the -y direction, which will cause the entire object block 7 to shift. That is, the probe 2 6 will gradually tilt within the -y range to achieve the -y scan.

[0056] Of course, the method for +x and -x scanning of the sample is not limited to the aforementioned design; it can also be as follows: like Figure 10 As shown, a planar xy coordinate system is established at the top of the left piezoelectric tube 2 and the right piezoelectric tube 2. The x-coordinate is established along the line connecting the axes of the two piezoelectric tubes 2, and the y-coordinate is established along the direction perpendicular to the x-coordinate. The origin of the x-coordinate and the y-coordinate is located at the midpoint of the line connecting the centers of the two piezoelectric tubes 2.

[0057] When the item to be scanned is placed on the sample holder 8 and an x-axis scan is required: (1) +x scan: Apply a voltage in the same direction to all piezoelectric blocks 201 on the left piezoelectric tube 2, and do not apply a voltage to all piezoelectric blocks 201 on the right piezoelectric tube 2, so that... Figure 3 From the perspective of the left side, the top of the piezoelectric tube 2 will extend upward, causing the slide bar 3 inside it to move upward. Since the top of the slide bar 3 is in contact with the inclined surface 701 of the block 7, when the top of the left slide bar 3 moves upward, the left end of the block 7 will be pushed upward and tilted. That is, the probe 2 6 gradually tilts within the +x range to achieve the +x scan.

[0058] (2) -x scan: Apply a voltage in the same direction to all piezoelectric blocks 201 on the right piezoelectric tube 2, and do not apply a voltage to all piezoelectric blocks 201 on the left piezoelectric tube 2, so as to Figure 3 From the perspective of the right side, the top of the piezoelectric tube 2 will extend upward, causing the slide bar 3 inside it to move upward. Since the top of the slide bar 3 is in contact with the inclined surface 701 of the block 7, when the top of the right slide bar 3 moves upward, the right end of the block 7 will be pushed upward and tilted. That is, the probe 2 6 gradually tilts within the -x range to achieve the -x scan.

[0059] Example 3: For example Figure 7 As shown, based on the above embodiment two, this embodiment proposes a control method for a scanning probe microscope, which controls the first piezoelectric tube and the second piezoelectric tube respectively using the following timing signals: (a') A piezoelectric elongation signal is applied to the first piezoelectric tube, and the left slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the left slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b') An inertial swing signal is applied to the first piezoelectric tube, which generates a displacement of the left slider as follows: , Satisfy: (1) and Same direction, (2) | |<| |; (c') Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the right slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d') An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e') Return to step (a') and repeat the process to achieve step-by-step displacement approximation.

[0060] Example 4: like Figure 8 As shown, this embodiment, based on Embodiment 1, further proposes a scanning probe microscope, including: a first support 9, a second support 10, a third support 11, and a fourth support 12; the first support 9 is fixed to the top of the left slide bar, the second support 10 is fixed to the top of the right slide bar, the third support 11 and the fourth support 12 are respectively disposed on the base 1, with the third support 11 located above the first support 9 and the fourth support 12 located above the second support 10; both the first piezoelectric tube and the second piezoelectric tube are XYZ piezoelectric scanning tubes, and probes 13 are disposed on both the first support 9 and the second support 10.

[0061] Example 5: For example Figure 8 As shown, based on the above embodiment four, this embodiment proposes a control method for a scanning probe microscope, which controls the first piezoelectric tube and the second piezoelectric tube respectively using the following timing signals: (a) When a piezoelectric elongation signal is applied to the first piezoelectric tube, the left slider moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (c). If no tunneling current is detected, this step is repeated until the total displacement of the left slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b) An inertial swing signal is applied to the first piezoelectric tube. Under the action of this signal, the displacement of the left slider is: , Satisfy: (1) and Same direction, (2) | |<| |; (c) Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (f). If no tunneling current is detected, this step is repeated until the total displacement of the right slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d) An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e) Return to step (a) and repeat the process to achieve step-by-step displacement approximation; (f) After the coarse approximation ends, the first piezoelectric tube and the second piezoelectric tube perform scanning imaging respectively.

[0062] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A dual-piezoelectric driven inertial motor, comprising: The base is characterized by further comprising: a first piezoelectric tube, a second piezoelectric tube, and a U-shaped sliding body; the first piezoelectric tube and the second piezoelectric tube are arranged parallel to each other along their axes, and one end of each is fixed to the base, while the other end is a free end; the two parallel arms of the U-shaped sliding body are respectively called the left sliding rod and the right sliding rod, which are elastically connected through a transition part at the bottom of the U-shaped sliding body, and the left sliding rod and the right sliding rod are respectively inserted parallel and coaxially into the inner walls of the first piezoelectric tube and the second piezoelectric tube, forming a structure in which the left sliding rod and the right sliding rod are elastically pressed against the inner walls of the first piezoelectric tube and the second piezoelectric tube, respectively.

2. The dual piezoelectric tube driven inertial motor according to claim 1, characterized in that, It also includes two sleeves, which are coaxially fixed to the inner walls of the free ends of the first and second piezoelectric tubes, respectively. The left and right sliding rods are coaxially inserted into the inner walls of the two sleeves, forming a structure in which the left and right sliding rods are elastically pressed against the inner walls of the two sleeves.

3. The dual piezoelectric tube driven inertial motor according to claim 2, characterized in that, The left and right slide rods are respectively provided with side edges along their length direction, and the side edges are linearly in contact with the sleeves of the inner walls of the first and second piezoelectric tubes.

4. The dual piezoelectric tube driven inertial motor according to claim 1, characterized in that, It also includes a storage block, which is placed at the top of the left and right slide bars.

5. The dual piezoelectric tube driven inertial motor according to claim 4, characterized in that, The adapter has a slit, and the horizontal opposing elastic force generated by the slit will elastically press the left and right slide rods against the inner walls of the first and second piezoelectric tubes, respectively.

6. The control method for a dual-piezoelectric-driven inertial motor according to claim 1, characterized in that, The first and second piezoelectric tubes are controlled by signals with the following timing sequence to complete one cycle of stepping: (1) Apply a piezoelectric elongation signal to the first piezoelectric tube, the elongation generating an inertial force on the left slide bar that is less than the maximum static friction force it experiences; (2) Apply a piezoelectric contraction signal to the first piezoelectric tube, the inertial force generated by the contraction on the left slide rod is greater than the maximum static friction force it experiences; (3) Apply a piezoelectric elongation signal to the second piezoelectric tube, the inertial force generated by the elongation on the right slide rod is less than the maximum static friction force it experiences; (4) Apply a piezoelectric contraction signal to the second piezoelectric tube, the inertial force generated by the contraction on the right slide rod is greater than the maximum static friction force it experiences.

7. A scanning probe microscope made using the dual piezoelectric tube driven inertial motor as described in claim 1, characterized in that, include: First support, second support, third support and fourth support; The first bracket is fixed to the top of the left slide bar, the second bracket is fixed to the top of the right slide bar, the third bracket and the fourth bracket are respectively disposed on the base, and the third bracket is located above the first bracket and the fourth bracket is located above the second bracket. The first piezoelectric tube and the second piezoelectric tube are both XYZ piezoelectric scanning tubes, and probes are disposed on both the first bracket and the second bracket.

8. A control method for a scanning probe microscope using a dual piezoelectric tube driven inertial motor as described in claim 7, characterized in that the first piezoelectric tube and the second piezoelectric tube are controlled respectively by the following timing signals: (a) When a piezoelectric elongation signal is applied to the first piezoelectric tube, the left slider moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (c). If no tunneling current is detected, this step is repeated until the total displacement of the left slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b) An inertial swing signal is applied to the first piezoelectric tube. Under the action of this signal, the displacement of the left slider is: , Satisfy: (1) and Same direction, (2) | |<| |; (c) Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe is used to detect whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, this step is terminated and the process jumps to step (f). If no tunneling current is detected, this step is repeated until the total displacement of the right slider reaches [value missing]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d) An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e) Return to step (a) and repeat the process to achieve step-by-step displacement approximation; (f) After the coarse approximation ends, the first piezoelectric tube and the second piezoelectric tube perform scanning imaging respectively.

9. A scanning probe microscope made using the dual piezoelectric tube driven inertial motor as described in claim 5, characterized in that, include: The fifth and sixth stents; The fifth bracket is fixed at the center of the object block, the sixth bracket is fixed on the base, and the sixth bracket is located above the fifth bracket. The first piezoelectric tube and the second piezoelectric tube are both XYZ piezoelectric scanning tubes, and the fifth bracket is equipped with a second probe.

10. A control method for a scanning probe microscope using a dual piezoelectric tube driven inertial motor as described in claim 9, characterized in that the first piezoelectric tube and the second piezoelectric tube are controlled respectively by the following timing signals: (a') A piezoelectric elongation signal is applied to the first piezoelectric tube, and the left slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the left slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the left slide bar; (b') An inertial swing signal is applied to the first piezoelectric tube, which generates a displacement of the left slider as follows: , Satisfy: (1) and Same direction, (2) | |<| |; (c') Apply a piezoelectric elongation signal to the second piezoelectric tube, and the right slide bar moves along the elongation direction. The probe checks whether a tunneling current exists between the probe tip and the sample under a bias voltage. If a tunneling current is detected, the subsequent steps are terminated, and scanning imaging measurements are performed. If no tunneling current is detected, the step is repeated until the total displacement of the right slider reaches [a certain value]. The inertial force generated during the elongation process is insufficient to overcome the maximum static friction force on the right slide bar; (d') An inertial swing signal is applied to the second piezoelectric tube, which generates a displacement of the right slide rod. , Satisfy: (1) and Same direction, (2) | |<| |; (e') Return to step (a') and repeat the process to achieve step-by-step displacement approximation.

11. The scanning method of a scanning probe microscope using a dual piezoelectric tube driven inertial motor as described in claim 9, characterized in that, Includes the following steps: Step 1: Apply a piezoelectric elongation signal to the first piezoelectric tube, causing the first piezoelectric tube and the slide bar to step upward to the target position. At this time, the slide bar will lift one end of the block upward, causing the block to tilt, so that the second probe deflects toward the second piezoelectric tube, thus achieving scanning in that direction. Step 2: Reset the slider and the block from Step 1; Step 3: Apply a piezoelectric elongation signal to the second piezoelectric tube, causing the second piezoelectric tube and the slide bar to move upwards in the same way. At this time, the slide bar will lift the other end of the block upwards, causing the block to tilt, so that the second probe deflects toward the first piezoelectric tube, thus achieving scanning in this direction. Step 4: Reset the slider and the block from Step 3 to complete the scan.

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