Grinding and polishing device and method for customizing movement of upper disc and measuring removal amount on line

Abstract

The invention discloses a polishing device and method capable of customizing upper disc movement and measuring removal amount on line. The plane grinding and polishing device comprises a lower disc and an upper disc, the lower disc comprises a plurality of coils, a light plate and a polishing pad which are sequentially arranged from bottom to top, the coils are arranged in a multi-phase staggered plane array mode, the upper disc comprises a magnet, an upper plate and a lower plate, the upper plate and the lower plate are used for fixing the magnet, and a workpiece is fixed to the lower side of the lower plate; the device further comprises a differential interferometer, a reference mirror is fixedly arranged on the shell, a measuring mirror is fixedly arranged on the upper disc, and the differential interferometer is connected with a laser device. Current is input into the coil through the motion control device, relative motion of the lower disc and the upper disc can be achieved, then workpiece polishing is achieved, the upper disc can move along any set track, and compared with a traditional single track, the robot is higher in moving freedom degree and can be suitable for polishing of complex paths; and online measurement of the removal amount in the workpiece polishing process can be realized.

Description

Technical Field

[0001] This invention relates to the field of precision machining technology, specifically to a polishing device and method with a customizable upper plate movement and online measurement of the amount of material removed. Background Technology

[0002] High-precision polishing is widely used in semiconductors, optical devices, and precision molds. Current conventional single-plane polishing equipment typically consists of a rotary-driven lower platen, an upper pressure loading mechanism, and a control panel. During processing, the workpiece is pressed against the rotating polishing disc by multiple pressure heads above for material removal. Most existing polishing devices rely on traditional motor-driven mechanical rotation and pressure to achieve the polishing motion, such as lead screws, gears, or belt drives. This approach suffers from problems such as a single path, poor trajectory flexibility, high control rigidity, significant mechanical wear, and slow response speed, making it difficult to meet the requirements of nanometer-level machining accuracy.

[0003] Meanwhile, to ensure the surface quality of the workpiece, precise control of the amount of material removed is required. However, most current equipment uses contact sensors for distance measurement or relies on manual offline inspection to determine the processing depth, which suffers from problems such as poor real-time performance, large measurement errors, and low efficiency. Especially when facing the need for removal at minute scales, accuracy and repeatability are difficult to guarantee.

[0004] In recent years, planar motors have been increasingly applied in the field of precision motion control due to their advantages such as non-contact operation, multiple degrees of freedom, and rapid response. Differential interferometers, as high-precision measuring devices based on laser interferometry, can achieve non-contact displacement measurement at the sub-micron or even nanometer level. Therefore, how to effectively combine planar motor drive technology with differential interferometry online measurement technology to construct a high-end quantitative grinding platform that is compact, accurate, and flexible in control has become a crucial technical problem that urgently needs to be solved in the field of precision manufacturing. Summary of the Invention

[0005] This invention provides a polishing device and method with customizable upper plate motion and online measurement of removal amount, which overcomes the above-mentioned problems existing in the prior art.

[0006] For the polishing apparatus, the technical solution of the present invention is as follows:

[0007] A planar polishing device with customizable upper plate movement and online measurement of removal volume includes a lower plate and an upper plate placed on top of the lower plate. The lower plate is fixed to a housing and includes multiple coils, a polishing plate, and a polishing pad arranged sequentially from bottom to top. The multiple coils are arranged in a multi-phase interlaced planar array, and the current input of the coils is controlled by a motion control device. The upper plate includes a magnet, an upper plate for fixing the magnet, and a lower plate. The lower side of the lower plate is used to fix the workpiece. The planar polishing device also includes a differential interferometer, which is mounted on the housing via a robotic arm. Correspondingly, a reference mirror is fixedly mounted on the housing, and a measuring mirror is fixedly mounted on the upper plate. The differential interferometer is connected to a laser device.

[0008] Compared to traditional single-plane polishing equipment with rotary drive and top-loading mechanisms, the upper plate provided by this invention can move along an arbitrarily set trajectory under the influence of a magnetic field to achieve polishing. The upper plate consists of a magnet and upper and lower plates with fixed magnets, eliminating the complex mechanical transmission structure of traditional top-loading mechanisms. Therefore, it avoids mechanical wear issues and polishing errors caused by mechanical transmission and wear, improving the control accuracy and flexibility of the polishing trajectory. The coils are arranged in a multi-phase interleaved planar array. According to the set trajectory, a motion control device can input currents of set magnitude, frequency, and phase along the X and Y directions. By inputting asymmetrical current into the coils, stable rotation of the upper plate around the Z-axis can be achieved without adding additional structures. The upper plate can move along any set trajectory; compared to traditional single-track systems, this invention offers higher degrees of freedom of movement and is suitable for polishing complex paths.

[0009] In implementing this invention, the plurality of coils can be elongated, ring-shaped coils. The polishing plate can be a fiberglass epoxy board, used to isolate the polishing fluid from the coils and protect the encapsulated coils. The polishing pad can be made of adhesive-backed polyurethane material, used for polishing the workpiece.

[0010] Furthermore, compared to traditional polishing equipment, this invention integrates a differential interferometer, enabling online measurement of the amount of material removed during polishing without disassembling the workpiece. The measuring mirror is fixed on the upper plate and moves with the workpiece, allowing for measurement of the amount of material removed at any polishing endpoint (starting position) along any trajectory. This invention achieves online ranging feedback with nanometer-level (less than 0.1 nm) resolution.

[0011] Preferably, in the aforementioned polishing device with customized upper plate movement and online measurement of removal volume, a drain pipe is connected to the outside of the housing, and the drain pipe is connected to a waste liquid tank. The drain pipe is used to discharge polishing waste liquid in real time to prevent waste liquid accumulation from affecting polishing accuracy.

[0012] Preferably, in the aforementioned polishing device with customized upper plate movement and online measurement of removal volume, a dripping device is provided on one side of the lower plate, and the dripping device is connected to a dripping tube. The dripping device is used to drip polishing liquid into the lower plate for polishing.

[0013] Preferably, in the aforementioned polishing device with customized upper plate movement and online measurement of removal amount, the surface of the polishing pad is provided with a polishing liquid flow groove.

[0014] Preferably, in the aforementioned polishing device with customized upper plate movement and online measurement of removal volume, the polishing liquid flow channel is grid-shaped.

[0015] Preferably, in the aforementioned polishing device with customized upper plate movement and online measurement of removal amount, the polishing pad is detachably attached to the polishing plate.

[0016] Regarding the polishing method, the technical solution of the present invention is as follows:

[0017] A planar polishing method that allows for customized upper plate motion and online measurement of removal volume, wherein the planar polishing method is implemented using the aforementioned planar polishing device that allows for customized upper plate motion and online measurement of removal volume. The planar polishing method includes the following steps:

[0018] Step 1: Select a portion of the coils to form the working plane. Based on the movement path, set the magnitude, frequency, and phase of the current distributed along the X and Y directions input to the selected coils. Different workpieces require different movement paths, such as figure-eight, arc, or straight reciprocating trajectories. Based on different trajectories, select multiple different coils to form the working plane. By inputting currents of corresponding magnitude, frequency, and phase along the X and Y directions to the selected coils, a corresponding magnetic field distribution is achieved, thereby realizing the movement trajectory of the upper plate under the corresponding magnetic field. By inputting asymmetrical current into the coils, stable rotation of the upper plate around the Z-axis can be achieved without adding additional structures. Therefore, this invention can achieve arbitrary trajectories through different current inputs, resulting in a high degree of freedom in the polishing path.

[0019] Step 2: The upper plate is located at the starting position of the working plane. The laser device controls the differential interferometer to emit two laser beams, which are directed at the reference mirror and the measuring mirror, respectively. The phase difference between the reference mirror and the measuring mirror is recorded as the initial interference phase difference.

[0020] Step 3: Start the motion control device, input the set current into the selected coil, and the upper plate moves along the set path under the action of the magnetic field, and the polishing pad polishes the workpiece.

[0021] Step 4: Polishing complete. The upper plate returns to the starting position. The laser device controls the differential interferometer to emit two laser beams, which are directed at the reference mirror and the measuring mirror respectively. The phase difference between the reference mirror and the measuring mirror is recorded as the endpoint interference phase difference. By converting the initial interference phase difference and the endpoint interference phase difference, the amount of workpiece removal is calculated. The measuring mirror and the workpiece move accordingly, and the amount of workpiece removal can be measured at different endpoint positions (starting positions). This invention can achieve online ranging feedback with nanometer-level (less than 0.1 nm) resolution.

[0022] Preferably, in the aforementioned polishing method with customized upper plate movement and online measurement of removal volume, step three further includes: activating the dripping device and setting the dripping frequency; the drain pipe continuously discharges waste polishing liquid into a waste liquid tank; step four further includes: shutting off the dripping device. The dripping device drips polishing liquid into the lower plate for workpiece polishing. Waste polishing liquid is continuously discharged into the waste liquid tank to prevent its accumulation from affecting polishing accuracy.

[0023] Preferably, in the aforementioned polishing method for customizing the upper plate motion and measuring the removal amount online, step three involves activating the motion control device and inputting a set current into the selected coil, including inputting an asymmetrical current into the selected coil. By inputting the asymmetrical current, stable rotation of the upper plate along the Z-axis can be achieved.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are as follows: (1) By controlling the magnetic field to drive the upper plate, there is no polishing error caused by mechanical transmission or wear, thus improving the polishing accuracy. (2) The lower plate adopts multiple coils, and the multiple coils are arranged in a multi-phase interlaced planar array. By inputting currents of different magnitudes, frequencies or phases along the X and Y directions to the selected coils, different magnetic field capabilities can be achieved, thereby enabling the upper plate to move along different polishing trajectories under the action of the magnetic field. Compared with traditional polishing equipment, the present invention has a higher degree of freedom in the polishing path and can meet the polishing requirements of complex paths. (3) By inputting asymmetrical current to the coils, the upper plate can be stably rotated around the Z axis without adding extra structures. (4) The present invention integrates a differential interferometer ranging system. By fixing the measuring mirror on the upper part of the upper plate, nanometer-level online ranging can be achieved at any polishing endpoint position (starting position), and the amount of material removed can be monitored in real time. The present invention can achieve high-precision measurement of polishing removal amount (<0.1µm). In summary, the present invention has a simple structure, low application cost, intelligent operation, and is easy to use. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural schematic diagram of the polishing device of the present invention, which allows for customized upper plate movement and online measurement of the amount of material removed.

[0026] Figure 2 This is the present invention. Figure 1 Enlarged schematic diagram of part A in the middle.

[0027] Figure 3 This is a schematic diagram of the split structure of the polishing device with customizable upper plate movement and online measurement of removal amount, and the lower plate of the present invention.

[0028] Figure 4 This is a three-dimensional structural schematic diagram and a partially enlarged schematic diagram of the polishing device for customizing the upper plate movement and measuring the amount of material removed in the online manner according to the present invention.

[0029] Figure 5 This invention Figure 4 The structural diagram of the shell is omitted.

[0030] Figure 6 This is a schematic diagram of the polishing device of the present invention, which allows for customized upper plate movement and online measurement of removal volume, omitting the dripping device, differential interferometer, and robotic arm.

[0031] The labels in the attached diagram are as follows: 1-House; 2-Opening / closing door; 3-Control display; 4-Button; 5-Waste liquid tank; 6-Lower plate; 61-Coil; 62-Polish plate; 63-Polishing pad; 7-Upper plate; 71-Upper plate; 72-Magnet; 73-Lower plate; 8-Drip device; 81-Drip tube; 9-Drain tube; 10-Differential interferometer; 11-Robotic arm; 12-Reference mirror; 13-Measuring mirror; 14-Laser device; 15-Motion control device. Detailed Implementation

[0032] The technical solution of the present invention will be further described in detail below through specific embodiments and with reference to the accompanying drawings, but this should not be construed as limiting the present invention. Contents not described in detail in the following embodiments are all common knowledge in the art or can be implemented using conventional technical means in the art.

[0033] Reference to embodiments of the present invention Figure 1-6 .

[0034] like Figure 1 As shown, the polishing device with customized upper plate movement and online measurement of removal volume includes a housing 1, which forms a worktable. A switch door 2 is provided on one side of the housing 1 for housing internal components. A control display 3 and buttons 4 are provided on the upper part of the housing 1 for easy operation and viewing by the operator.

[0035] like Figure 1 , Figure 2 , Figure 3 , Figure 6As shown, a lower plate 6 is disposed on the upper part of the housing 1. The lower plate 6 includes multiple coils 61, a polishing plate 62, and a polishing pad 63 arranged sequentially from bottom to top. To achieve high-precision trajectory control of the upper plate 7 in the XY plane and its Z-axis rotation function, the coils 61 are arranged in a multi-phase interlaced planar coil array structure, and the coils 61 are long strip-shaped ring structures. This arrangement of coils 61, by inputting currents with set magnitude, frequency, and phase along the X and Y directions, can generate a continuous and smooth magnetic field gradient in the working plane, realizing flexible, continuous, and programmable trajectory movement of the upper plate 7. Asymmetric current is passed through the coils 61, and through asymmetric current excitation, stable rotation of the upper plate 7 around the Z-axis can be achieved without adding additional structures. The arrangement of coils 61 in this invention not only improves the system control accuracy and response speed but also has advantages such as compact structure, easy heat dissipation, and easy integration, providing key support for achieving high-precision, customizable path polishing operations. In this embodiment, the polishing plate 62 is a fiberglass epoxy board, used to isolate the polishing liquid from contact with the coil 61 and protect the encapsulated coil 61. The polishing pad 63 is made of adhesive-backed polyurethane material and is used to polish the workpiece.

[0036] like Figure 2 and Figure 4 As shown, an upper plate 7 is provided on the upper part of the lower plate 6. The upper plate 7 is opposite to the lower plate 6, and its area is smaller than that of the lower plate 6, facilitating free movement relative to the lower plate 6. The upper plate 7 includes a lower plate 73, with a magnet 72 embedded in the upper part of the lower plate 73. An upper plate 71 is provided on the upper part of the magnet 72, and the upper plate 71 is bolted to the lower plate 73 to fix the magnet 72. The workpiece to be polished is fixed at the lower part of the lower plate 73, and the workpiece is fixed by means of paraffin adhesive or other methods. The positioning accuracy of the upper plate 7 is better than ±5μm, and the repeatability can reach ±1nm. Existing traditional mechanical polishing platforms rely on ball screws or linear guides for movement, and their positioning accuracy is generally on the order of ±10μm. The repeatability is difficult to be better than ±5μm, and the accuracy decays over long-term operation due to mechanical friction and clearance. In this invention, the upper plate 7 can achieve X and Y axis translation and Z axis rotation control relative to the lower plate 6, which can effectively avoid problems caused by mechanical friction and wear, improve motion accuracy and response speed, and is suitable for high-precision planar polishing. In this embodiment of the invention, the lower plate 73 is made of low carbon steel, and the upper plate 71 is made of glass fiber epoxy board, used to protect the encapsulated magnet 72.

[0037] like Figure 1 , Figure 2 , Figure 4As shown, a differential interferometer 10 is installed at the starting point of the upper plate 7, and the differential interferometer 10 is mounted on the upper part of the housing 1 via a multi-axis robotic arm 11. A fixed reference mirror 12 is installed on the lower part of the differential interferometer 10 on the housing 1, and a fixed measuring mirror 13 is installed on the upper part of the upper plate 7. The measuring mirror 13 moves with the upper plate 7. During operation, the differential interferometer 10 emits two laser beams, which are respectively irradiated onto the reference mirror 12 and the measuring mirror 13 to obtain the phase difference between them, which is recorded in real time in the laser device 14 of the controller. Before polishing begins, a measurement is taken at the starting position of the upper plate 7. After polishing is completed, the upper plate 7 returns to the starting position, and a measurement is taken again to obtain a new phase difference. By comparing the phase difference measured before and after polishing, the actual material removal amount of the workpiece can be accurately calculated, achieving online ranging feedback with nanometer-level resolution.

[0038] like Figure 1 , Figure 2 , Figure 4 , Figure 5 As shown, a dripping device 8 is provided on one side of the upper plate 7, containing polishing liquid. The dripping device 8 drips polishing liquid onto the lower plate 6 through a dripping pipe 81. A drain pipe 9 is connected to the outside of the housing 1. The drain pipe 9 is used to discharge polishing waste liquid from the lower plate 6 and to guide the polishing waste liquid into a waste liquid tank 5. A laser device 14 and a motion control device 15 are provided inside the housing 1. The laser device 14 is used to control the differential interferometer 10, and the motion control device 15 is used to output current to control the relative movement of the upper plate 7 and the lower plate 6.

[0039] The working principle of this invention is as follows: by passing current through coil 61, a magnetic field is formed, and magnet 72 moves under the action of the magnetic field, causing upper plate 7 to move relative to lower plate 6. The workpiece fixed at the lower part of upper plate 7 moves relative to polishing pad 63, so that polishing pad 63 polishes the workpiece.

[0040] The polishing and removal amount measurement method of the present invention is as follows:

[0041] (1) Before the motion control device 15 powers the coil 61, the laser device 14 controls the differential interferometer 10 to emit two lasers, which are directed at the reference mirror 12 and the measuring mirror 13 respectively. The phase difference between the reference mirror 12 and the measuring mirror 13 at this time is recorded as the initial interference phase difference.

[0042] (2) The motion control device 15 supplies current to the coil 61, and the energized coil 61 generates a magnetic field. Under the action of the magnetic field, the magnet 72 causes the lower plate 6 and the upper plate 7 to move relative to each other. By precisely controlling the magnitude and phase of the current in each coil 61 of the coil array arranged on the lower plate 6, a controllable dynamic magnetic field can be formed in the XY direction, driving the upper plate 7 to move arbitrarily in the plane along a set trajectory. By simultaneously applying a specific combination of currents to the coils 61, the upper plate 7 generates a resultant force along the X-axis and Y-axis, realizing trajectory following control. At the same time, in order to realize the rotational movement of the upper plate 7 around the Z-axis, an asymmetrical current distribution can be applied to the coils 61 to form a resultant torque, thereby realizing the rotation of the upper plate 7. Under the action of the magnetic field, the upper plate 7 can achieve high-precision movement along any path on the surface of the polishing pad 63 in the area of ​​the lower plate 6, including a figure-eight trajectory, an arc path, a straight reciprocating motion, and other complex trajectory modes, to adapt to the precision polishing operation under different process requirements. For example, if a square wave or triangular wave current is applied to coil 61, the upper plate 7 can move back and forth along a straight line; if a sinusoidal current with a 90° phase difference between the X and Y axes is applied to coil 61, the upper plate 7 can move along an arc trajectory; if a sinusoidal signal with a frequency ratio of 1:2 or a specific phase difference is applied to coil 61 in the X and Y directions, the upper plate 7 can move along a figure-eight trajectory. In summary, by using numerical control to modulate the current waveform in real time, a custom trajectory can be achieved.

[0043] (3) Turn on the automatic dripping device 8, select a suitable polishing liquid, and set the dripping frequency to ensure process stability.

[0044] (4) After polishing, the upper plate 7 returns to its initial position. At this time, the laser device 14 controls the differential interferometer 10 to emit two laser beams, which are directed at the reference mirror 12 and the measuring mirror 13 respectively. The phase difference between the reference mirror 12 and the measuring mirror 13 at this time is recorded as the endpoint interference phase difference. The amount of material removed from the workpiece after polishing is calculated by using the initial interference phase difference and the endpoint interference phase difference. This invention can achieve online high-precision detection (down to the nanometer level) and feedback control without disassembling the workpiece. This invention can detect the amount of material removed from the workpiece to be less than 0.1 micrometers.

[0045] (5) Polishing waste liquid is discharged into the waste liquid tank through the drain pipe 9. Excess polishing liquid is automatically discharged into the tank to prevent liquid accumulation from interfering with the ranging system.

[0046] To illustrate in detail the polishing method of the present invention, which allows for customized upper plate movement and online measurement of removal volume, several specific embodiments are provided below:

[0047] Example Trajectory type X-direction current Y-direction current Polishing pressure Polishing time Material removal amount Remove uniformity error Surface roughness (Ra) Example 1 Straight reciprocating trajectory 2A, 50Hz, phase increment 30° 0.5A, DC 20 N 30min ~180 nm Increase by approximately 5% Improved from 20 nm to ~7 nm Example 2 The trajectory of the character "∞" 1.5A, 40Hz 1.5A, 20Hz, 90° phase difference 15 N 20min 0.8 μm in the center, 0.7 μm at the edge. Increase by approximately 15% Improved from 15 nm to 5 nm Example 3 Spiral extension trajectory 2A, 60Hz, phase progression 2A, 60Hz, phase progression 15 N 40min ~250 nm Increase by approximately 3% Improved from 18 nm to ~6 nm

[0048] Example 1: Polishing a Φ20mm optical glass sheet along a straight reciprocating trajectory

[0049] The lower plate 6 uses a rectangular array of long coils, with several coils arranged in both the X and Y directions. A 2A sinusoidal current with a frequency of 50 Hz is passed through adjacent coils in the X direction, with the phases increasing by 30° in succession, thereby driving the upper plate 7 to form a reciprocating linear motion along the X direction; the coils in the Y direction maintain a DC bias current of 0.5 A.

[0050] Driven by the aforementioned current, the upper plate 7 achieves a reciprocating linear trajectory of ±5 mm, with the pressure stabilized at 20 N to ensure uniform contact between the workpiece and the polishing pad.

[0051] Using an optical glass sheet with a diameter of approximately Φ20 mm as the workpiece, after polishing for 30 minutes, a differential interferometer 10 performed online measurements at the starting and ending points, calculating that the material removal amount was approximately 180 nm, the overall uniformity improved by approximately 5%, and the surface roughness improved from Ra≈20 nm to approximately 7 nm. This trajectory mode is suitable for rapid pre-processing of large-scale substrates.

[0052] Example 2: Polishing a Φ20mm optical glass sheet along a spiral expansion trajectory

[0053] Using the same rectangular coil array arrangement as in Example 1, alternating currents with the same amplitude but different frequencies are passed through in the X and Y directions, respectively. The current amplitude in the X direction is 1.5 A, and the frequency is 40 Hz; the current amplitude in the Y direction is 1.5 A, and the frequency is 20 Hz, and the current is 90° out of phase with the X direction signal.

[0054] In this way, the upper plate 7 forms a Lissajous trajectory in the plane, i.e., an "∞" shaped trajectory, covering an area of ​​±3mm × ±3mm. The higher speed at the trajectory intersections helps to improve the uniformity of removal.

[0055] During this process, the polishing pressure was controlled at 15 N. Using an optical glass sheet with a diameter of approximately Φ20 mm as the workpiece, after polishing for 20 minutes, the differential interferometer 10 showed that the average removal depth in the central area was approximately 0.8 μm, and in the edge area approximately 0.7 μm. The overall uniformity was improved by approximately 15%, and the surface roughness was improved from Ra≈15 nm to 5 nm. This trajectory mode is suitable for uniform fine polishing of optical glass sheets.

[0056] Example 3: Polishing a Φ20mm optical glass sheet along an "∞" shaped trajectory

[0057] The 4×4 coil group in the center of the array is selected for focused driving. Alternating current with an amplitude of 2 A and a frequency of 60 Hz is applied to the X and Y direction coils respectively, with the phases of adjacent coils progressively increasing to synthesize a circular magnetic field. By gradually adjusting the phase difference over time, the trajectory of the upper plate 7 expands outward from the center, forming a spiral motion with a radius of 0–5 mm.

[0058] This spiral trajectory can cover the entire polishing area, effectively avoiding the accumulation of textures caused by repeated paths. During the polishing process, the polishing pressure is controlled at 15 N.

[0059] Using an optical glass sheet with a diameter of approximately Φ20 mm as the workpiece, after polishing for 40 minutes, the differential interferometer 10 detected a total removal amount of approximately 250 nm, an improvement of approximately 20% in surface convergence, an improvement of approximately 3% in overall uniformity, and an improvement in surface roughness from Ra≈18 nm to approximately 6 nm. This mode is suitable for fine finishing of high-precision mirror areas.

[0060] In summary, by selecting appropriately distributed coils 61, the motion control device 15 inputs current in the X and Y directions, and sets the current magnitude, frequency, and phase according to the motion trajectory. The upper plate 7 moves along the predetermined trajectory, and the polishing pad 63 polishes the workpiece. Before and after polishing, the differential interferometer 10 measures the initial interference phase difference and the final interference phase difference, respectively, and calculates the actual amount of material removed by polishing. Using this invention can improve the uniformity of material removal and improve surface roughness.

[0061] The foregoing general description of the invention and its specific embodiments should not be construed as a limitation on the technical solution of the invention. Those skilled in the art, based on the disclosure of this application, can add, reduce, or combine the disclosed technical features in the foregoing general description and / or specific embodiments (including examples) without departing from the constituent elements of the invention, to form other technical solutions within the scope of protection of this invention.

Claims

1. A polishing device with customizable upper plate motion and online measurement of removal volume, characterized in that: The planar polishing device includes a lower plate (6) and an upper plate (7) placed on the upper part of the lower plate (6). The lower plate (6) is fixed on the housing (1). The lower plate (6) includes multiple coils (61), a polishing plate (62), and a polishing pad (63) arranged sequentially from bottom to top. The multiple coils (61) are arranged in a multi-phase interlaced planar array. The current input of the coils (61) is controlled by a motion control device (15). The upper plate (7) includes a magnet (72), an upper plate (71) for fixing the magnet (72), and a lower plate (73). The lower side of the lower plate (73) is used to fix the workpiece. The planar polishing device also includes a differential interferometer (10). The differential interferometer (10) is set on the housing (1) by a robotic arm (11). Correspondingly, a reference mirror (12) is fixed on the housing (1), and a measuring mirror (13) is fixed on the upper plate (7). The differential interferometer (10) is connected to a laser device (14).

2. The planar polishing device with customizable upper plate movement and online measurement of removal amount according to claim 1, characterized in that: The shell (1) is connected to a drain pipe (9), which is connected to a waste liquid tank (5).

3. The planar polishing device for customizing upper plate movement and measuring removal amount online according to claim 1, characterized in that: A dripping device (8) is provided on one side of the lower plate (6), and the dripping device (8) is connected to a dripping tube (81).

4. The planar polishing device with customizable upper plate movement and online measurement of removal amount according to claim 1, characterized in that: The polishing pad (63) has a polishing liquid flow groove on its surface.

5. The planar polishing device for customizing upper plate movement and measuring removal amount online according to claim 4, characterized in that: The polishing fluid flow channel is grid-shaped.

6. The planar polishing device for customizing upper plate movement and measuring removal amount online according to claim 1, characterized in that: The polishing pad (63) is detachably attached to the polishing plate (62).

7. A planar polishing method with customizable upper plate motion and online measurement of removal amount, characterized in that: The planar polishing method is implemented using the planar polishing device described in claim 1, which allows for customized upper plate movement and online measurement of the amount removed. The method includes the following steps: Step 1: Select a portion of the coils (61) to form the working plane. According to the movement path, set the magnitude, frequency and phase of the current distributed along the X and Y directions input to the selected coils (61); Step 2: The upper plate (7) is located at the starting position of the working plane. The laser device (14) controls the differential interferometer (10) to emit two laser beams, which are directed at the reference mirror (12) and the measuring mirror (13) respectively. The phase difference between the reference mirror (12) and the measuring mirror (13) is recorded as the initial interference phase difference. Step 3: Start the motion control device (15), input the set current into the selected coil (61), the upper plate (7) moves along the set path under the action of the magnetic field, and the polishing pad (63) polishes the workpiece; Step 4: Polishing is complete. The upper plate (7) returns to the starting position. The laser device (14) controls the differential interferometer (10) to emit two laser beams, which are directed at the reference mirror (12) and the measuring mirror (13) respectively. The phase difference between the reference mirror (12) and the measuring mirror (13) is recorded as the endpoint interference phase difference. The initial interference phase difference and the endpoint interference phase difference are converted to calculate the amount of workpiece removed.

8. The planar polishing method for customizing upper plate motion and measuring removal amount online according to claim 7, characterized in that: Step three also includes: starting the dripping device (8) and setting the dripping frequency; the drain pipe (9) discharges the waste polishing liquid into the waste liquid bucket (5) in real time; Step four also includes: turning off the dripping device (8).

9. The polishing method for customizing upper plate movement and measuring removal amount online according to claim 7, characterized in that: In step three, the motion control device (15) is activated, and the set current is input to the coil (61), including inputting an asymmetrical current to the coil (61).

Images