Elliptical ultrasonic vibration assisted processing device and method for scanning probe

Abstract

The present invention relates to an elliptical ultrasonic vibration-assisted processing device and method for a scanning probe, belonging to the field of micro-nano processing technology. The device comprises a vibration table and two groups of vibration generating modules; the vibration table comprises a vibration table head and two groups of variable amplitude flexible hinges, the vibration table head is used to fix a sample, and the two groups of variable amplitude flexible hinges are distributed at 90 degrees on both sides of the vibration table head and are used to amplify resonance deformation; the two groups of vibration generating modules are respectively in contact with the two groups of variable amplitude flexible hinges, and are used to apply excitation signals with the same frequency, the same amplitude, and different phases, and stimulate the X and Y resonances of the vibration table in the ultrasonic frequency band, so that the sample generates ultrasonic elliptical resonance in the XY plane, can obtain a larger amplitude at a smaller working frequency, and then generate elliptical vibration in the ultrasonic frequency band at the sample end, thereby improving chip discharge behavior and processing quality, reducing normal force during processing, reducing probe wear, and improving the service life of the probe when processing hard materials.

Description

Technical Field

[0001] The present invention belongs to the field of micro-nano processing technology, and in particular relates to an elliptical ultrasonic vibration assisted processing device and method for a scanning probe. Background Art

[0002] With the rapid development of technologies such as integrated circuits, micro-electromechanical systems, and optoelectronic devices, increasingly higher requirements are being placed on the machining accuracy and surface quality of micro- and nanoscale structures. Scanning probe machining methods, due to their extremely high resolution and controllability, are widely used in fields such as nanoindentation, nanoscratch, localized oxidation, and microstructure machining. However, traditional scanning probe machining, which primarily relies on uniaxial (usually vertical) loading, still has certain limitations in terms of material removal efficiency, surface morphology control, and probe life. Especially when faced with machining tasks involving high-hardness materials, its machining capabilities urgently need to be improved.

[0003] Ultrasonic vibration-assisted machining technology has demonstrated significant advantages in the micromachining of hard and brittle materials in recent years. By superimposing tiny ultrasonic vibrations on the tool or workpiece, it can effectively reduce cutting forces, minimize machining stress concentration, improve chip removal, and extend tool life. In particular, two-dimensional ultrasonic elliptical vibration, by introducing high-frequency vibrations with phase difference control in two orthogonal directions, creates an elliptical trajectory between the tool and workpiece. This enables periodic cutting and separation behavior at the submicron and even nanometer scales, facilitating precise control of material fracture and removal.

[0004] However, currently, elliptical ultrasonic vibration machining systems are mostly used at the macroscale or in traditional machine tool structures. Existing elliptical vibration devices used in scanning probe machining systems operate at frequencies of only a few hundred Hz, limiting machining efficiency and cutting performance. Compact, two-dimensional ultrasonic elliptical vibration platforms suitable for scanning probes are still lacking. The current technical bottleneck in this field is how to effectively integrate ultrasonic vibration-assisted machining with the high-resolution displacement control capabilities of scanning probes, and achieve adjustable and stable elliptical vibration trajectories at the nanoscale. Summary of the Invention

[0005] The object of the present invention is to provide an elliptical ultrasonic vibration assisted processing device and method for a scanning probe, so as to solve the problems such as the lack of an adaptive ultrasonic elliptical vibration platform in the existing scanning probe processing system.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] The present invention relates to an elliptical ultrasonic vibration-assisted processing device for a scanning probe, which comprises a vibration table and two groups of vibration generating modules; the vibration table comprises a vibration table head and two groups of variable amplitude flexible hinges, the vibration table head is used to fix a sample, and the two groups of variable amplitude flexible hinges are distributed at 90 degrees on both sides of the vibration table head and are used to amplify resonant deformation; the two groups of vibration generating modules are respectively in contact with the two groups of variable amplitude flexible hinges, and are used to apply excitation signals with the same frequency, the same amplitude and different phases, and stimulate the X and Y resonances of the vibration table in the ultrasonic frequency band, so that the sample generates ultrasonic elliptical resonance in the XY plane.

[0008] Preferably, the vibration generating modules include a piezoelectric ceramic sheet, an electrode sheet and a fixed hinge; the fixed hinge corresponds to the variable amplitude flexible hinge, and is used to clamp the piezoelectric ceramic sheet and the electrode sheet between the corresponding fixed hinge and the variable amplitude flexible hinge; the electrode sheet is arranged between the positive and negative plates of the piezoelectric ceramic sheet, and is used to input a signal to the positive electrode of the ceramic sheet, and the piezoelectric ceramic sheet is used to receive the signal and excite the vibration mode of the vibration generating module.

[0009] Preferably, the vibration generating modules also include a counterweight block, which is fixed to the corresponding fixed hinge through a connecting stud and is used to adjust the resonant frequency difference in the X and Y directions; the connecting stud passes through the fixed hinge and presses the piezoelectric ceramic sheet onto the variable amplitude flexible hinge.

[0010] Preferably, a sample balance block is further provided on the bottom surface of the vibration table for balancing the mass distribution of the sample after the vibration table is installed, so that the mass distribution of the vibration table is symmetrical relative to the XY plane.

[0011] Preferably, it also includes a base and a support plate, the vibration generating module is arranged on the base, the support plate is arranged on the base through an adjusting screw, the vibration table is arranged on the support plate, and the support plate is used to provide auxiliary support to the vibration table and fine-tune the height and tilt angle of the vibration table.

[0012] Preferably, the cross-sectional shape of the variable amplitude flexible hinge is an asymmetric trapezoid.

[0013] The present invention also relates to an elliptical ultrasonic vibration assisted machining method for a scanning probe, which comprises the following steps:

[0014] S1. Fix the sample and sample balance weight to the top and bottom surfaces of the vibration table head respectively;

[0015] S2. Apply excitation signals of the same frequency, amplitude, and phase to the two vibration generating modules. The vibration is amplified by the variable amplitude flexible hinge and stimulates the X and Y resonance of the vibration table in the ultrasonic frequency band, causing the sample to produce ultrasonic elliptical resonance in the XY plane.

[0016] S3. According to the processing requirements, the amplitude and phase of the excitation signal input to the two groups of vibration generating modules are changed to achieve ultrasonic elliptical vibration-assisted processing with different trajectories.

[0017] Preferably, in S1, the sample and the sample balance block are symmetrically mounted on the top and bottom surfaces of the vibration table head using quick-drying glue or paraffin.

[0018] Preferably, the vibration table is arranged on a support plate, and S3 further adjusts the height of the support plate and the vibration table by adjusting screws arranged on the support plate to reduce the out-of-plane vibration of the sample in the Z direction.

[0019] Preferably, the phase difference between the two groups of vibration generating modules in S2 and S3 is 90°.

[0020] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0021] 1. The present invention relates to an elliptical ultrasonic vibration-assisted machining device for a scanning probe. The device comprises a vibration table, comprising a vibration table head and two sets of variable-amplitude flexible hinges. The vibration table head is used to secure the sample. The two sets of variable-amplitude flexible hinges are arranged at 90° on either side of the vibration table head and are used to amplify resonant deformation, generating elliptical vibration at the sample end. The variable-amplitude flexible hinges have an asymmetric trapezoidal cross-section, which can reduce out-of-plane vibration in the Z direction, making it more suitable for scanning probe machining systems. Two sets of piezoelectric ceramic plates synergistically excite the resonant vibration modes of the sample vibration table in the X and Y directions, imparting an elliptical vibration trajectory to the sample being machined. This enables periodic cutting and separation between the probe and the sample at the submicron or even nanometer scale, improving chip removal and, consequently, machining quality. The present invention reduces the contact area between the probe and the sample being machined by using an elliptical trajectory, thereby reducing normal force during machining, reducing probe wear, and improving probe life when machining hard materials. Furthermore, the frequency of the scanning probe's elliptical vibration-assisted machining can be increased to the ultrasonic frequency band, thereby increasing the efficiency of scanning probe-based elliptical vibration-assisted machining.

[0022] 2. The elliptical ultrasonic vibration assisted processing device for a scanning probe involved in the present invention is provided with a sample balance block on the bottom surface of the vibration table to balance the mass distribution of the sample after the vibration table is installed, so that the mass distribution of the vibration table is symmetrical relative to the XY plane, and an auxiliary support plate is added to reduce the Z-direction off-plane vibration of the processed sample and reduce the impact of the Z-direction off-plane vibration on the processing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a structural diagram of an elliptical ultrasonic vibration assisted machining device for a scanning probe according to the present invention;

[0024] Figure 2It is a schematic diagram of the connection relationship between the fixed hinge and the counterweight;

[0025] Figure 3 Schematic diagram of the structure of the support plate;

[0026] Figure 4 It is the top view of the vibration table; Figure 5 is the side view of the vibration table;

[0027] Figure 6 The vibration effect diagram of the variable amplitude flexible hinge with a rectangular cross section;

[0028] Figure 7 The vibration effect diagram of the variable amplitude flexible hinge with an asymmetric trapezoidal cross section;

[0029] Figure 8 This is the elliptical vibration trajectory generated by the sample vibration table head.

[0030] Figure numerals: 1-vibration table, 2-sample, 3-piezoelectric ceramic sheet, 4-electrode sheet, 5-fixed hinge, 6-counterweight, 7-base, 8-support plate, 9-connecting stud, 10-setting screw, 11-adjusting screw, 12-vibration table head, 13-amplitude flexible hinge, 14-sample balance block. DETAILED DESCRIPTION

[0031] In order to further understand the content of the present invention, the present invention is described in detail with reference to the examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0032] Refer to the attached Figure 1 As shown, the present invention relates to an elliptical ultrasonic vibration-assisted processing device for a scanning probe, which includes a base 7, a support plate 8, a vibration table 1, and two groups of vibration generating modules. The base 7 is used to connect the elliptical ultrasonic vibration-assisted processing device and the scanning probe system through a fixed hinge 5. The support plate 8 and the vibration generating module are directly mounted on the base 7, and the vibration table 1 is set on the support plate 8. The resonant frequencies corresponding to the X and Y direction resonant vibration modes of the vibration table 1 and the two groups of vibration generating modules are set in the ultrasonic frequency band. By respectively exciting these two vibration modes, elliptical vibrations in the ultrasonic frequency band can be generated in combination within the XY plane.

[0033] Refer to the attached Figure 4 As shown in FIG, the vibration table 1 includes a vibration table head 12 and two sets of variable amplitude flexible hinges 13. The vibration table head 12 is used to fix the sample 2. The two sets of variable amplitude flexible hinges 13 are distributed at 90 degrees on both sides of the vibration table head 12. The top view of the variable amplitude flexible hinge 13 is a perfect circular flexible hinge. The resonance energy density distribution is adjusted by changing the cross-sectional area, so that the deformation is concentrated in the small cross-section, thereby amplifying the resonance deformation. Figure 5As shown, the bottom surface of the vibration table 1 is also provided with a sample balance block 14, which is used to balance the mass distribution of the vibration table 1 after the sample 2 is installed, so that the mass distribution of the vibration table 1 is symmetrical relative to the XY plane, thereby reducing the out-of-plane vibration in the Z direction.

[0034] The two groups of vibration generating modules are respectively in contact with the two groups of variable amplitude flexible hinges 13, and are used to apply excitation signals of the same frequency, same amplitude and different phases, and stimulate the X and Y direction resonance of the vibration table 1 in the ultrasonic frequency band, so that the sample 2 generates ultrasonic elliptical resonance in the XY plane. Figure 1 As shown, the vibration generating modules include a piezoelectric ceramic sheet 3, an electrode sheet 4 and a fixed hinge 5; the fixed hinge 5 corresponds to the variable amplitude flexible hinge 13, and is used to clamp the piezoelectric ceramic sheet 3 and the electrode sheet 4 between the corresponding fixed hinge 5 and the variable amplitude flexible hinge 13; the electrode sheet 4 is arranged between the positive and negative plates of the piezoelectric ceramic sheet 3, and is used to input a signal to the positive electrode of the ceramic sheet, and the piezoelectric ceramic sheet 3 is used to receive the signal and excite the vibration mode of the vibration generating module. The vibration generating modules also include a counterweight 6, which is fixed to the corresponding fixed hinge 5 by a connecting stud 9, and is used to adjust the resonant frequency difference in the X and Y directions, and the connecting stud passes through the fixed hinge 5 and presses the piezoelectric ceramic sheet 3 onto the variable amplitude flexible hinge 13, as shown Figure 2 shown.

[0035] The support plate 8 is set on the base 7 by adjusting screws 11. Specifically, two sets of diagonal holes of the support plate 8 are respectively provided with two threaded holes and two through holes. Two set screws 10 are passed through the two through holes and connected to the two threaded holes on the base 7. Two adjusting screws 11 are threadedly connected to the two threaded holes of the support plate 8. After the screw threads pass through the threaded holes, they contact the upper surface of the base 7. The vibration table 1 is set on the support plate 8. Figure 3 As shown, in this way, the support plate 8 is not only used to provide auxiliary support for the vibration table 1, but also can be used to adjust the height and tilt angle of the vibration table 1.

[0036] Refer to the attached Figure 6-7 As shown, the cross section of the variable amplitude flexible hinge 13 can be a uniform rectangular cross section or an asymmetric trapezoidal cross section. Figure 6 As shown in (a)-(c), the vibration process of the vibration table when it is excited will cause the variable amplitude flexible hinge 13 to produce compression and tension deformation. When the variable amplitude flexible hinge has a rectangular cross-section, it exerts a relative compressive or tensile force on the vibration table head 12 during the compression or tension process, thereby causing the vibration table head to deform under force, causing the surface of the sample 2 to tilt, which manifests as Z-direction off-plane vibration of the processed surface during the processing. Figure 7As shown in (a)-(c), compared to a variable-amplitude flexure hinge 13 with a uniform cross-section, the variable-amplitude flexure hinge 13 with an asymmetric trapezoidal cross-section generates parasitic motion in the Z direction during deformation. This compensates for the tilting of the sample 2 plane caused by the vibration displacement of a conventional rectangular cross-section hinge. This stabilizes the vibration of the machined surface and reduces the impact of the Z-direction off-plane vibration caused by the tilting on the machining process. Therefore, the variable-amplitude flexure hinge 13 with an asymmetric trapezoidal cross-section is preferred in this embodiment.

[0037] Based on the above-mentioned elliptical ultrasonic vibration-assisted processing device for a scanning probe, the present invention also relates to an elliptical ultrasonic vibration-assisted processing method for a scanning probe, which comprises the following steps:

[0038] S1. Use quick-drying glue or paraffin to fix the sample 2 and the sample balance block 14 to the top and bottom surfaces of the vibration table head 12, respectively;

[0039] S2. Apply excitation signals of the same frequency, amplitude and different phases to the two sets of vibration generating modules with a phase difference of 90°. The vibration is amplified by the variable amplitude flexible hinge 13, and the X and Y directions of the vibration table 1 in the ultrasonic frequency band are stimulated to resonate, so that the sample 2 generates ultrasonic elliptical resonance in the XY plane, forming a Figure 8 The elliptical vibration trajectory shown;

[0040] S3. According to the processing requirements, the height of the support plate 8 and the vibration table 1 is adjusted by the adjustment screw 11 set on the support plate 8, the off-plane vibration of the sample 2 in the Z direction is reduced, the amplitude and phase of the excitation signal input to the two groups of vibration generating modules are changed, and ultrasonic elliptical vibration-assisted processing with different trajectories is realized.

[0041] The elliptical ultrasonic vibration assisted processing device and method of the scanning probe involved in the present invention are used to assist the scanning probe processing of micro-nano scale structures such as integrated circuits, micro-electromechanical systems and optoelectronic devices, so as to improve processing accuracy and surface quality.

[0042] The present invention has been described in detail above with reference to the embodiments. However, the contents described are only preferred embodiments of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. An elliptical ultrasonic vibration-assisted machining device for a scanning probe, characterized in that: It includes a vibration table and two groups of vibration generating modules; the vibration table includes a vibration table head and two groups of variable amplitude flexible hinges, the vibration table head is used to fix the sample, and the two groups of variable amplitude flexible hinges are distributed at 90 degrees on both sides of the vibration table head, and the cross-sectional shape of the variable amplitude flexible hinge is an asymmetric trapezoid, which is used to amplify the resonant deformation and reduce the off-plane vibration in the Z direction; the two groups of vibration generating modules are respectively in contact with the two groups of variable amplitude flexible hinges, and are used to apply excitation signals with the same frequency, the same amplitude and different phases, and stimulate the X and Y resonance of the vibration table in the ultrasonic frequency band, so that the sample generates ultrasonic elliptical resonance in the XY plane.

2. The elliptical ultrasonic vibration-assisted machining device for a scanning probe according to claim 1, characterized in that: The vibration generating modules all include a piezoelectric ceramic sheet, an electrode sheet and a fixed hinge; the fixed hinge corresponds to the variable amplitude flexible hinge, and is used to clamp the piezoelectric ceramic sheet and the electrode sheet between the corresponding fixed hinge and the variable amplitude flexible hinge; the electrode sheet is arranged between the positive and negative plates of the piezoelectric ceramic sheet, and is used to input a signal to the positive electrode of the ceramic sheet, and the piezoelectric ceramic sheet is used to receive the signal and excite the vibration mode of the vibration generating module.

3. The elliptical ultrasonic vibration-assisted machining device for a scanning probe according to claim 2, characterized in that: The vibration generating modules also include a counterweight block, which is fixed to the corresponding fixed hinge through a connecting stud and is used to adjust the resonant frequency difference in the X and Y directions; the connecting stud passes through the fixed hinge and presses the piezoelectric ceramic piece onto the variable amplitude flexible hinge.

4. The elliptical ultrasonic vibration-assisted machining device for a scanning probe according to claim 1, characterized in that: The bottom surface of the vibration table is also provided with a sample balance block for balancing the mass distribution of the vibration table after the sample is installed, so that the mass distribution of the vibration table is symmetrical relative to the XY plane.

5. The elliptical ultrasonic vibration-assisted machining device for a scanning probe according to claim 1, characterized in that: It also includes a base and a support plate. The vibration generating module is arranged on the base. The support plate is arranged on the base through an adjusting screw. The vibration table is arranged on the support plate. The support plate is used to provide auxiliary support for the vibration table and fine-tune the height and tilt angle of the vibration table.

6. An elliptical ultrasonic vibration assisted machining method for a scanning probe, characterized in that: It includes the following steps: S1. Fix the sample and sample balance weight to the top and bottom surfaces of the vibration table head respectively; S2. Applying excitation signals of the same frequency, amplitude, and phase to the two vibration generating modules, amplifying the vibrations through the variable amplitude flexible hinge, and exciting the vibration table to resonate in the X and Y directions in the ultrasonic frequency band, causing the sample to produce ultrasonic elliptical resonance in the XY plane. The cross-sectional shape of the variable amplitude flexible hinge is an asymmetric trapezoid, which amplifies the resonant deformation while reducing the out-of-plane vibration in the Z direction; S3. According to the processing requirements, the amplitude and phase of the excitation signal input to the two groups of vibration generating modules are changed to achieve ultrasonic elliptical vibration-assisted processing with different trajectories.

7. The elliptical ultrasonic vibration-assisted machining method for a scanning probe according to claim 6, characterized in that: The S1 uses quick-drying glue or paraffin to symmetrically mount the sample and the sample balance block on the top and bottom surfaces of the vibration table head.

8. The elliptical ultrasonic vibration-assisted machining method for a scanning probe according to claim 6, characterized in that: The vibration table is arranged on the support plate, and the S3 further adjusts the height of the support plate and the vibration table by adjusting screws arranged on the support plate to reduce the off-plane vibration of the sample in the Z direction.

9. The elliptical ultrasonic vibration-assisted machining method for a scanning probe according to claim 6, characterized in that: The phase difference between the two groups of vibration generating modules in S2 and S3 is 90°.

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