Nested dual-frequency ultrasonic compound vibrator for chemical mechanical polishing

Abstract

The application relates to the technical field of chemical mechanical polishing, in particular to a nested double-frequency ultrasonic compound vibrator for chemical mechanical polishing, which comprises a holding sleeve, a low-frequency ultrasonic vibrator coaxially arranged in the holding sleeve, a vibration surface of the low-frequency ultrasonic vibrator, a flange plate fixedly assembled to the outer side of the holding sleeve, a connecting seat arranged on the lower surface of the flange plate, a connecting plate fixed to the lower surface of the connecting seat, an end cover coaxially fixed to the lower surface of the connecting plate, a convex ring A and a convex ring B coaxially arranged on the lower surface of the end cover, a high-frequency ultrasonic vibration plate arranged below the end cover, a convex ring C and a convex ring D coaxially arranged on the upper surface of the high-frequency ultrasonic vibration plate, the outer side of the convex ring D matched with the inner side of the convex ring B, and a high-frequency piezoelectric ceramic piece fixed to the upper surface of the high-frequency ultrasonic vibration plate. The application solves the problems of slow polishing speed and poor surface quality after polishing of the existing chemical mechanical polishing technology, and is suitable for the fields of semiconductor manufacturing and optical device processing.

Description

Technical Field

[0001] This invention relates to the field of chemical mechanical polishing technology, specifically a nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing. Background Technology

[0002] Chemical mechanical polishing (CMP) is an ultra-precision machining technology that relies on the synergistic effect of chemicals and machinery to remove material from the surface of workpieces. It is widely used in semiconductor manufacturing, optical device processing, and other fields. However, in practical applications, existing CMP technologies suffer from limitations due to their inherent principles. On the one hand, the mass transfer efficiency of the polishing slurry is low, and the chemical reaction rate is slow. On the other hand, the mechanical removal rate is also slow, resulting in slow polishing speeds and poor surface quality after polishing. Therefore, it is necessary to invent a nested dual-frequency ultrasonic composite oscillator for CMP to solve the problems of slow polishing speeds and poor surface quality in existing CMP technologies. Summary of the Invention

[0003] To address the problems of slow polishing speed and poor surface quality in existing chemical mechanical polishing (CMP) technologies, this invention provides a nested dual-frequency ultrasonic composite vibrator for CMP.

[0004] This invention is achieved using the following technical solution:

[0005] A nested dual-frequency ultrasonic composite transducer for chemical mechanical polishing includes a cylindrical retaining sleeve; a low-frequency ultrasonic transducer with its vibration surface facing downward is coaxially mounted inside the retaining sleeve; and a loading disk is mounted on the vibration surface of the low-frequency ultrasonic transducer.

[0006] A flange is fixedly mounted on the outer side of the retaining sleeve; a connecting seat is installed on the lower surface of the flange; a connecting plate with an annular structure is fixed on the lower surface of the connecting seat, and the connecting plate coaxially surrounds the retaining sleeve; an end cap with an annular structure is fixed coaxially on the lower surface of the connecting plate; a convex ring A and a convex ring B are coaxially extended on the lower surface of the end cap, and the convex ring B is located outside the convex ring A.

[0007] A high-frequency ultrasonic transducer plate with a ring structure is provided below the end cap; a convex ring C and a convex ring D are coaxially extended on the upper surface of the high-frequency ultrasonic transducer plate, and the convex ring D is located outside the convex ring C; a through hole is provided between the inner and outer sides of the convex ring C; the upper surface of the convex ring C and the lower surface of the convex ring A are mated together; the outer side of the convex ring D and the inner side of the convex ring B are mated together; a high-frequency piezoelectric ceramic sheet is fixed on the upper surface of the high-frequency ultrasonic transducer plate, and the high-frequency piezoelectric ceramic sheet is located between the convex ring C and the convex ring D.

[0008] Furthermore, a four-channel conductive slip ring is coaxially arranged inside the retaining sleeve; a gap is left between the outer surface of the outer ring of the four-channel conductive slip ring and the inner surface of the retaining sleeve; a drive shaft is fixedly assembled inside the inner ring of the four-channel conductive slip ring; a radially arranged support beam is fixed between the lower side of the drive shaft and the inner surface of the retaining sleeve, and the support beam is located above the low-frequency ultrasonic transducer; the first pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the low-frequency ultrasonic transducer; the second pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the high-frequency piezoelectric ceramic sheet.

[0009] Furthermore, a temperature monitor is fixed to the outer surface of the convex ring B.

[0010] Furthermore, a fastening screw hole is provided through the side wall of the retaining sleeve; a fastening bolt is inserted into the fastening screw hole, and the tail end of the fastening bolt presses tightly against the side of the low-frequency ultrasonic transducer; the inner side of the retaining sleeve is a stepped surface that is thinner at the top and thicker at the bottom, and the upper surface of the low-frequency ultrasonic transducer contacts the transition section of the stepped surface.

[0011] Furthermore, the vibration surface of the low-frequency ultrasonic transducer is provided with blind holes; the loading disk is fixedly embedded in the blind holes.

[0012] Furthermore, the flange surface has a through-hole A; the connecting seat has a through-hole B; a mounting bolt passes through both mounting holes A and B, and the head of the mounting bolt is pressed tightly against the flange; a mounting nut is screwed onto the mounting bolt, and the mounting nut is pressed tightly against the connecting seat.

[0013] Furthermore, the connector and end cap are both made of iron; the connecting plate is made of magnetic material; the connecting plate is adsorbed and fixed to the lower surface of the connector; and the end cap is adsorbed and fixed to the lower surface of the connecting plate.

[0014] Furthermore, the inner surface of the convex ring B is provided with an internal thread; the outer surface of the convex ring D is provided with an external thread; the outer surface of the convex ring D and the inner surface of the convex ring B are screwed together.

[0015] Furthermore, the lower surface of the retaining sleeve is provided with a radially arranged drainage groove A; the lower surface of the high-frequency ultrasonic transducer is provided with a radially arranged drainage groove B, and the drainage groove B and the drainage groove A are interconnected.

[0016] Furthermore, the side wall of the retainer is provided with a perforated hole.

[0017] This invention discloses a nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing, which achieves a dual improvement in polishing speed and post-polishing surface quality through a nested high- and low-frequency structure. Specifically, this invention utilizes high-frequency ultrasonic vibration to induce an acoustic flow effect in the polishing slurry. This acoustic flow effect significantly improves the mass transfer efficiency and chemical reaction rate of the polishing slurry and effectively lowers the cavitation threshold, making cavitation more likely to occur. Simultaneously, it utilizes low-frequency ultrasonic vibration to induce a vigorous cavitation effect in the polishing slurry. This vigorous cavitation effect generates high-energy shock waves and microjets, thereby significantly increasing the mechanical removal rate. Due to the significant improvement in the mass transfer efficiency, chemical reaction rate, and mechanical removal rate of the polishing slurry, both the polishing speed and the post-polishing surface quality are significantly enhanced.

[0018] This invention effectively solves the problems of slow polishing speed and poor surface quality after polishing in existing chemical mechanical polishing technology, and is applicable to fields such as semiconductor manufacturing and optical device processing. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention.

[0020] Figure 2 yes Figure 1 Partial structural diagram Figure 1 .

[0021] Figure 3 yes Figure 2 Partial structural diagram Figure 1 .

[0022] Figure 4 yes Figure 3 Another structural diagram from another angle.

[0023] Figure 5 yes Figure 4 Partial structural diagram Figure 1 .

[0024] Figure 6 yes Figure 5 A sectional view.

[0025] Figure 7 yes Figure 4 Partial structural diagram Figure 2 .

[0026] Figure 8 yes Figure 2 Partial structural diagram Figure 2 .

[0027] Figure 9 yes Figure 8 Another structural diagram from another angle.

[0028] Figure 10 yes Figure 1 Partial structural diagram Figure 2 .

[0029] Figure 11 yes Figure 10 Partial structural diagram Figure 1 .

[0030] Figure 12 yes Figure 10 Partial structural diagram Figure 2 .

[0031] Figure 13 yes Figure 12 Partial structural diagram Figure 1 .

[0032] Figure 14 yes Figure 13 Another structural diagram from another angle.

[0033] Figure 15 yes Figure 12 Partial structural diagram Figure 2 .

[0034] Figure 16 yes Figure 12 Another structural diagram from another angle.

[0035] Figure 17 yes Figure 16 A sectional view.

[0036] Figure 18 yes Figure 1 Another structural diagram from another angle.

[0037] In the diagram: 1-Retaining sleeve, 1.1-Fasting screw hole, 1.2-Drainage slot A, 1.3-Hollow hole, 2-Low-frequency ultrasonic transducer, 2.1-Blind hole, 3-Carrying tray, 4-Flange, 4.1-Assembly hole A, 5-Connecting seat, 5.1-Assembly hole B, 6-Connecting plate, 7-End cap, 7.1-Protruding ring A, 7.2-Protruding ring B, 8-High-frequency ultrasonic transducer plate, 8.1-Protruding ring C, 8.2-Protruding ring D, 8.3-Wire hole, 8.4-Drainage slot B, 9-High-frequency piezoelectric ceramic sheet, 10-Outer ring of four-channel conductive slip ring, 11-Inner ring of four-channel conductive slip ring, 12-Drive shaft, 13-Support beam, 14-Temperature monitor, 15-Fasting bolt, 16-Assembly bolt, 17-Assembly nut. Detailed Implementation

[0038] A nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing includes a cylindrical retaining sleeve 1; a low-frequency ultrasonic vibrator 2 with its vibration surface facing downward is coaxially mounted inside the retaining sleeve 1; and a carrier disk 3 is mounted on the vibration surface of the low-frequency ultrasonic vibrator 2.

[0039] A flange 4 is fixedly mounted on the outer side of the retaining sleeve 1; a connecting seat 5 is installed on the lower surface of the flange 4; a connecting plate 6 with an annular structure is fixed on the lower surface of the connecting seat 5, and the connecting plate 6 coaxially surrounds the retaining sleeve 1; an end cover 7 with an annular structure is fixed on the lower surface of the connecting plate 6; a convex ring A7.1 and a convex ring B7.2 are coaxially extended on the lower surface of the end cover 7, and the convex ring B7.2 is located outside the convex ring A7.1.

[0040] Below the end cap 7, a high-frequency ultrasonic transducer 8 with a ring structure is provided; a convex ring C8.1 and a convex ring D8.2 are coaxially extended on the upper surface of the high-frequency ultrasonic transducer 8, and the convex ring D8.2 is located outside the convex ring C8.1; a through hole 8.3 is provided between the inner and outer sides of the convex ring C8.1; the upper surface of the convex ring C8.1 and the lower surface of the convex ring A7.1 are mated together; the outer side of the convex ring D8.2 and the inner side of the convex ring B7.2 are mated together; a high-frequency piezoelectric ceramic sheet 9 is fixed on the upper surface of the high-frequency ultrasonic transducer 8, and the high-frequency piezoelectric ceramic sheet 9 is located between the convex ring C8.1 and the convex ring D8.2.

[0041] During operation, the polishing pad of the chemical mechanical polishing machine is coated with polishing fluid. A retaining sleeve 1 is eccentrically positioned on the upper surface of the polishing pad and rotatably clamped within the fixture of the chemical mechanical polishing machine. The workpiece adheres to the lower surface of the workpiece tray 3, and the workpiece is in contact with the upper surface of the polishing pad. A low-frequency ultrasonic generator and a high-frequency ultrasonic generator are located beside the chemical mechanical polishing machine. The low-frequency ultrasonic transducer 2 is electrically connected to the low-frequency ultrasonic generator. The high-frequency piezoelectric ceramic plate 9 is electrically connected to the high-frequency ultrasonic generator.

[0042] The specific working process is as follows: First, the chemical mechanical polishing machine is started, causing the polishing pad to rotate. Based on the friction between the retaining sleeve 1 and the polishing pad, the polishing pad drives the retaining sleeve 1 to rotate within the fixture. The retaining sleeve 1 drives the low-frequency ultrasonic transducer 2, the carrier plate 3, the workpiece, the flange 4, the connecting seat 5, the connecting plate 6, the end cap 7, the high-frequency ultrasonic transducer 8, and the high-frequency piezoelectric ceramic sheet 9 to rotate together, thereby causing the workpiece to rub against the polishing pad. Then, the low-frequency ultrasonic generator and the high-frequency ultrasonic generator are started. The low-frequency ultrasonic generator converts the mains power into an ultrasonic frequency alternating current signal and transmits the ultrasonic frequency alternating current signal to the low-frequency ultrasonic transducer 2. The low-frequency ultrasonic transducer 2 converts the ultrasonic frequency alternating current signal into low-frequency ultrasonic vibration, thereby causing the invention and the workpiece to undergo low-frequency ultrasonic vibration together. The high-frequency ultrasonic generator converts the mains power into an ultrasonic frequency alternating current signal and transmits the ultrasonic frequency alternating current signal to the high-frequency piezoelectric ceramic sheet 9. The high-frequency piezoelectric ceramic sheet 9 converts the ultrasonic frequency alternating current signal into high-frequency ultrasonic vibration, thereby causing the invention and the workpiece to undergo high-frequency ultrasonic vibration together.

[0043] Based on the friction between the workpiece and the polishing pad, and in conjunction with the polishing slurry, chemical-mechanical polishing of the workpiece is achieved. During the polishing process, high-frequency ultrasonic vibration induces an acoustic flow effect in the polishing slurry. This acoustic flow effect significantly improves the mass transfer efficiency and chemical reaction rate of the polishing slurry, and effectively lowers the cavitation threshold, making cavitation more likely to occur. Simultaneously, low-frequency ultrasonic vibration induces a vigorous cavitation effect in the polishing slurry. This vigorous cavitation effect generates high-energy shock waves and microjets, thereby significantly increasing the mechanical removal rate. Due to the significantly improved mass transfer efficiency, chemical reaction rate, and mechanical removal rate of the polishing slurry, both the polishing speed and the post-polishing surface quality are significantly enhanced.

[0044] A four-channel conductive slip ring is coaxially arranged inside the retaining sleeve 1; a gap is left between the outer side of the outer ring 10 of the four-channel conductive slip ring and the inner side of the retaining sleeve 1; a drive shaft 12 is fixedly assembled inside the inner ring 11 of the four-channel conductive slip ring; a radially arranged support beam 13 is fixed between the lower side of the drive shaft 12 and the inner side of the retaining sleeve 1, and the support beam 13 is located above the low-frequency ultrasonic transducer 2; the first pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the low-frequency ultrasonic transducer 2; the second pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the high-frequency piezoelectric ceramic sheet 9. During operation, the first pair of outer ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the low-frequency ultrasonic generator. The second pair of outer ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the high-frequency ultrasonic generator. The low-frequency ultrasonic generator converts the mains power into an ultrasonic frequency alternating current signal, and transmits the ultrasonic frequency alternating current signal to the low-frequency ultrasonic transducer 2 through the four-channel conductive slip ring. The high-frequency ultrasonic generator converts mains power into an ultrasonic alternating current signal, and transmits the ultrasonic alternating current signal to the high-frequency piezoelectric ceramic sheet 9 through a four-channel conductive slip ring.

[0045] A temperature monitor 14 is fixed to the outer surface of the convex ring B7.2. During operation, the temperature monitor 14 monitors and displays the operating temperature of the invention in real time, allowing operators to flexibly adjust the operating time of the invention accordingly.

[0046] The retaining sleeve 1 has a through-hole 1.1 for fastening screws; a fastening bolt 15 passes through the fastening screw hole 1.1, and the tail end of the fastening bolt 15 presses tightly against the side of the low-frequency ultrasonic transducer 2; the inner surface of the retaining sleeve 1 is a stepped surface that is thinner at the top and thicker at the bottom, and the upper surface of the low-frequency ultrasonic transducer 2 contacts the transition section of the stepped surface. During operation, this design ensures that the low-frequency ultrasonic transducer 2 is securely installed inside the retaining sleeve 1.

[0047] The vibrating surface of the low-frequency ultrasonic transducer 2 has a blind hole 2.1; the carrier plate 3 is fixedly embedded in the blind hole 2.1. During operation, this design ensures that the carrier plate 3 is securely mounted on the vibrating surface of the low-frequency ultrasonic transducer 2.

[0048] A mounting hole A4.1 is provided through the surface of the flange 4; a mounting hole B5.1 is provided through the connecting seat 5; a mounting bolt 16 passes through both mounting holes A4.1 and B5.1, and the head of the mounting bolt 16 is tightly pressed against the flange 4; a mounting nut 17 is screwed onto the mounting bolt 16, and the mounting nut 17 is tightly pressed against the connecting seat 5. During operation, this design ensures that the connecting seat 5 is securely installed on the lower surface of the flange 4.

[0049] Both the connector 5 and the end cap 7 are made of iron; the connecting plate 6 is made of magnetic material; the connecting plate 6 is magnetically fixed to the lower surface of the connector 5; the end cap 7 is magnetically fixed to the lower surface of the connecting plate 6. During operation, this design allows for quick assembly and disassembly between the connector 5 and the end cap 7.

[0050] The inner surface of the convex ring B7.2 is provided with internal threads; the outer surface of the convex ring D8.2 is provided with external threads; the outer surface of the convex ring D8.2 and the inner surface of the convex ring B7.2 are screwed together. During operation, this design enables quick assembly and disassembly between the end cap 7 and the high-frequency ultrasonic transducer 8.

[0051] The lower surface of the retaining sleeve 1 has a radially arranged drainage groove A1.2; the lower surface of the high-frequency ultrasonic transducer 8 has a radially arranged drainage groove B8.4, and the drainage groove B8.4 is connected to the drainage groove A1.2. During operation, polishing fluid can be replenished at any time through the drainage groove B8.4 and the drainage groove A1.2.

[0052] The side wall of the retaining sleeve 1 has a through hole 1.3. During operation, the heat generated by the low-frequency ultrasonic transducer 2 can be quickly dissipated through the through hole 1.3.

[0053] In specific implementation, the low-frequency ultrasonic generator is a kilohertz ultrasonic generator, and the high-frequency ultrasonic generator is a megahertz ultrasonic generator. Both pairs of inner ring terminals of the four-channel conductive slip ring face downwards. The first pair of inner ring terminals is electrically connected to a pair of terminals of the low-frequency ultrasonic transducer 2 via a pair of wires located inside the retaining sleeve 1. The second pair of inner ring terminals is electrically connected to a pair of terminals of the high-frequency piezoelectric ceramic plate 9 via another pair of wires, and these wires simultaneously pass through the gap between the outer ring 10 of the four-channel conductive slip ring and the retaining sleeve 1, as well as through the wire hole 8.3. Both pairs of outer ring terminals of the four-channel conductive slip ring face upwards. The first pair of outer ring terminals is electrically connected to a pair of terminals of the low-frequency ultrasonic generator via a pair of wires located outside the retaining sleeve 1. The second pair of outer ring terminals is electrically connected to a pair of terminals of the high-frequency ultrasonic generator via another pair of wires located outside the retaining sleeve 1. The number of fastening screw holes 1.1, the number of perforated holes 1.3, the number of support beams 13, and the number of fastening bolts 15 are all four, and the four fastening screw holes 1.1, four perforated holes 1.3, four support beams 13, and four fastening bolts 15 are all equidistantly arranged circumferentially. The number of drainage slots A1.2, the number of assembly holes A4.1, the number of connecting seats 5, the number of assembly holes B5.1, the number of wire holes 8.3, the number of drainage slots B8.4, the number of assembly bolts 16, and the number of assembly nuts 17 are all eight, and the eight drainage slots A1.2, eight assembly holes A4.1, eight connecting seats 5, eight assembly holes B5.1, eight wire holes 8.3, eight drainage slots B8.4, eight assembly bolts 16, and eight assembly nuts 17 are all equidistantly arranged circumferentially. The number of high-frequency piezoelectric ceramic plates 9 is twelve, and the twelve high-frequency piezoelectric ceramic plates 9 are equidistantly arranged circumferentially.

[0054] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A nested dual-frequency ultrasonic composite oscillator for chemical mechanical polishing, characterized in that: It includes a retaining sleeve (1) with a cylindrical structure; a low-frequency ultrasonic transducer (2) with its vibration surface facing downward is coaxially installed inside the retaining sleeve (1); a carrier plate (3) is installed on the vibration surface of the low-frequency ultrasonic transducer (2). A flange (4) is fixedly mounted on the outer side of the retaining sleeve (1); a connecting seat (5) is installed on the lower surface of the flange (4); a connecting plate (6) with an annular structure is fixed on the lower surface of the connecting seat (5), and the connecting plate (6) is coaxially surrounding the retaining sleeve (1); an end cap (7) with an annular structure is coaxially fixed on the lower surface of the connecting plate (6); a convex ring A (7.1) and a convex ring B (7.2) are coaxially extended on the lower surface of the end cap (7), and the convex ring B (7.2) is located outside the convex ring A (7.1); A high-frequency ultrasonic transducer plate (8) with a ring structure is provided below the end cap (7); a convex ring C (8.1) and a convex ring D (8.2) are coaxially extended on the upper surface of the high-frequency ultrasonic transducer plate (8), and the convex ring D (8.2) is located outside the convex ring C (8.1); a through hole (8.3) is provided between the inner and outer sides of the convex ring C (8.1); the upper surface of the convex ring C (8.1) and the lower surface of the convex ring A (7.1) are connected to each other; the outer side of the convex ring D (8.2) and the inner side of the convex ring B (7.2) are matched with each other; a high-frequency piezoelectric ceramic sheet (9) is fixed on the upper surface of the high-frequency ultrasonic transducer plate (8), and the high-frequency piezoelectric ceramic sheet (9) is located between the convex ring C (8.1) and the convex ring D (8.2); During operation, the polishing pad of the chemical mechanical polishing machine is coated with polishing liquid; the retaining sleeve (1) is placed eccentrically on the upper surface of the polishing pad and is rotatably clamped in the fixture of the chemical mechanical polishing machine; the workpiece is adhered to the lower surface of the workpiece (3) and is in contact with the upper surface of the polishing pad; a low-frequency ultrasonic generator and a high-frequency ultrasonic generator are provided on the side of the chemical mechanical polishing machine; the low-frequency ultrasonic transducer (2) is electrically connected to the low-frequency ultrasonic generator; the high-frequency piezoelectric ceramic sheet (9) is electrically connected to the high-frequency ultrasonic generator. The specific working process is as follows: First, start the chemical mechanical polishing machine to make the polishing pad rotate; based on the friction between the retaining sleeve (1) and the polishing pad, the polishing pad drives the retaining sleeve (1) to rotate in the fixture, and the retaining sleeve (1) drives the low-frequency ultrasonic transducer (2), the carrier plate (3), the workpiece, the flange (4), the connecting seat (5), the connecting plate (6), the end cap (7), the high-frequency ultrasonic transducer plate (8), and the high-frequency piezoelectric ceramic sheet (9) to rotate together, thereby making the workpiece rub against the polishing pad; then, start the low-frequency ultrasonic generator and the high-frequency ultrasonic generator; the low-frequency ultrasonic... The generator converts mains power into an ultrasonic frequency alternating current signal and transmits the ultrasonic frequency alternating current signal to a low-frequency ultrasonic transducer (2). The low-frequency ultrasonic transducer (2) converts the ultrasonic frequency alternating current signal into low-frequency ultrasonic vibration, thereby causing the composite transducer and the workpiece to undergo low-frequency ultrasonic vibration together. The high-frequency ultrasonic generator converts mains power into an ultrasonic frequency alternating current signal and transmits the ultrasonic frequency alternating current signal to a high-frequency piezoelectric ceramic sheet (9). The high-frequency piezoelectric ceramic sheet (9) converts the ultrasonic frequency alternating current signal into high-frequency ultrasonic vibration, thereby causing the composite transducer and the workpiece to undergo high-frequency ultrasonic vibration together. Based on the friction between the workpiece and the polishing pad, and in conjunction with the polishing fluid, chemical mechanical polishing of the workpiece is achieved. During the polishing process, high-frequency ultrasonic vibration induces the polishing fluid to produce an acoustic flow effect, while low-frequency ultrasonic vibration induces the polishing fluid to produce a violent cavitation effect.

2. The nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: A four-channel conductive slip ring is coaxially arranged inside the retaining sleeve (1); a gap is left between the outer side of the outer ring (10) of the four-channel conductive slip ring and the inner side of the retaining sleeve (1); a drive shaft (12) is fixedly assembled inside the inner ring (11) of the four-channel conductive slip ring; a support beam (13) arranged radially is fixed between the lower side of the drive shaft (12) and the inner side of the retaining sleeve (1), and the support beam (13) is located above the low-frequency ultrasonic transducer (2); the first pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the low-frequency ultrasonic transducer (2); the second pair of inner ring terminals of the four-channel conductive slip ring are electrically connected to a pair of terminals of the high-frequency piezoelectric ceramic sheet (9).

3. The nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: A temperature monitor (14) is fixed to the outer side of the convex ring B (7.2).

4. The nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The retaining sleeve (1) has a through-hole (1.1) for fastening screws; a fastening bolt (15) is inserted into the fastening screw hole (1.1), and the tail end of the fastening bolt (15) presses against the side of the low-frequency ultrasonic transducer (2); the inner side of the retaining sleeve (1) is a stepped surface that is thinner at the top and thicker at the bottom, and the upper surface of the low-frequency ultrasonic transducer (2) is in contact with the transition section of the stepped surface.

5. The nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The vibration surface of the low-frequency ultrasonic transducer (2) is provided with a blind hole (2.1); the carrier disk (3) is fixedly embedded in the blind hole (2.1).

6. The nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: A mounting hole A (4.1) is provided through the surface of the flange (4); a mounting hole B (5.1) is provided through the connecting seat (5); a mounting bolt (16) is provided through the mounting holes A (4.1) and B (5.1), and the head of the mounting bolt (16) is pressed against the flange (4); a mounting nut (17) is screwed onto the mounting bolt (16), and the mounting nut (17) is pressed against the connecting seat (5).

7. A nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The connector (5) and end cap (7) are both made of iron; the connecting plate (6) is made of magnetic material; the connecting plate (6) is attached to the lower surface of the connector (5); the end cap (7) is attached to the lower surface of the connecting plate (6).

8. A nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The inner side of the convex ring B (7.2) is provided with an internal thread; the outer side of the convex ring D (8.2) is provided with an external thread; the outer side of the convex ring D (8.2) and the inner side of the convex ring B (7.2) are screwed together.

9. A nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The lower surface of the retaining sleeve (1) is provided with a radially arranged drainage groove A (1.2); the lower surface of the high-frequency ultrasonic transducer (8) is provided with a radially arranged drainage groove B (8.4), and the drainage groove B (8.4) and the drainage groove A (1.2) are interconnected.

10. A nested dual-frequency ultrasonic composite vibrator for chemical mechanical polishing according to claim 1, characterized in that: The side wall of the retaining sleeve (1) is provided with a hollow hole (1.3).

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