Grinding pad trimming device and chemical mechanical grinding method

Abstract

The invention provides a polishing pad trimming device and a chemical mechanical polishing method.The polishing pad trimming device comprises a mechanical arm, a first connecting part, a reversing driving structure, a second connecting part, a first trimmer and a second trimmer, the first connecting part is connected with the mechanical arm, the reversing driving structure is connected with the first connecting part, and the second connecting part is connected with the second trimmer. The second connecting part is provided with a first mounting surface and a second mounting surface which are perpendicular to each other, and is connected with the reversing driving structure so as to rotate under the driving of the reversing driving structure to exchange the positions of the first mounting surface and the second mounting surface; the first dresser is mounted on the first mounting surface through a first supporting piece, and the dresser disc surface is parallel to the first mounting surface; the second dresser is mounted on the second mounting surface through a second supporting piece, and the dresser disc surface is parallel to the second mounting surface; the grinding pad trimming device can adjust different surface states of the grinding pad in different stages of a grinding process, and can reduce the frequency of machine maintenance.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductors and relates to a polishing pad dressing device and a chemical mechanical polishing method. Background Art

[0002] Chemical Mechanical Polishing, also known as Chemical Mechanical Planarization, is a global surface planarization technology. During the polishing process, the wafer rotates on the wafer carrier, and the polishing pad rotates on the polishing table at the same time. The chemical polishing agent is delivered to the polishing pad, and the wafer contacts the polishing pad under pressure, achieving surface planarization through chemical and mechanical forces.

[0003] During the wafer polishing process, the solid particles in the chemical abrasive and the materials removed by mechanical friction on the wafer fill the grooves on the polishing pad, reducing the polishing speed and efficiency; at the same time, as the polishing process proceeds, the protrusions on the polishing pad will be quickly worn, further reducing the efficiency of the polishing pad; and during the polishing process, the speed of the center and edge of the polishing pad is different, which will also cause the surface flatness of the polishing pad to be poor. Therefore, keeping the grooves on the surface of the polishing pad clean / flat is extremely important in the chemical mechanical polishing process.

[0004] In the existing process, when grinding materials of different hardness, it is necessary to ensure high grinding efficiency and reduce the roughness of the wafer surface. This requires the use of a dresser (disk) to dress the grinding pad during the grinding process so that the grinding pad has different surface states. In the early and middle stages of grinding, it is necessary to increase the dressing of the surface morphology of the grinding pad to make the surface roughness of the grinding pad higher to improve the grinding efficiency; in the later stages of grinding, it is necessary to reduce the friction of the dresser on the grinding pad to make the surface roughness of the grinding pad lower, so as to repair the mechanical scratches on the wafer surface and reduce the surface roughness of the wafer.

[0005] At present, the degree of dressing of the polishing pad surface by a single dresser is limited, and it cannot meet the requirements of adjusting the different surface conditions of the polishing pad during a polishing process. In addition, each chamber of the existing polishing equipment is only equipped with one mechanical arm and can only be equipped with one dresser, which cannot meet the requirements of high-end processes.

[0006] Therefore, how to provide a polishing pad dressing device to optimize the regulating effect of the dresser on the surface state of the polishing pad during chemical mechanical polishing has become an important technical problem that needs to be solved urgently by those skilled in the art.

[0007] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and facilitating the understanding of those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0008] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a polishing pad dressing device and a chemical mechanical polishing method, which are used to solve the problem that the existing polishing pad dressing device is difficult to dress the polishing pad to different states according to actual needs in a chemical mechanical polishing process.

[0009] To achieve the above-mentioned object and other related objects, the present invention provides a grinding pad dressing device, comprising:

[0010] Robotic arm;

[0011] A first connection part, connected to the robotic arm;

[0012] A reversing drive structure connected to the first connecting portion;

[0013] A second connection portion, having a first mounting surface and a second mounting surface perpendicular to each other, wherein the second connection portion is connected to the reversing drive structure so as to rotate under the drive of the reversing drive structure so that the positions of the first mounting surface and the second mounting surface are interchanged;

[0014] A first trimmer is mounted on the first mounting surface via a first support member, and a disk surface of the first trimmer is parallel to the first mounting surface;

[0015] The second trimmer is mounted on the second mounting surface via a second support member, and the disk surface of the second trimmer is parallel to the second mounting surface.

[0016] Optionally, when the second connecting portion is driven by the reversing drive structure to rotate 180°, the positions of the first mounting surface and the second mounting surface are interchanged.

[0017] Optionally, the reversing drive structure has a rotating output shaft, and the second connecting portion is connected to the rotating output shaft; or the reversing drive structure has an output gear, and the second connecting portion has a linked internal gear ring meshing with the output gear.

[0018] Optionally, the reversing drive structure includes a motor or a rotary cylinder.

[0019] Optionally, the rotary cylinder is provided with a pneumatic buffer.

[0020] Optionally, the first support member includes a first mounting plate, a second mounting plate and a trimmer disk angle adjustment component, the first mounting plate and the second mounting plate are opposite to each other and are spaced apart, the trimmer disk angle adjustment component is located between the first mounting plate and the second mounting plate and includes a plurality of spaced apart connecting columns, and the lengths of the plurality of connecting columns are independently adjustable; the second support member adopts the same structure as the first support member.

[0021] Optionally, the first trimmer and the second trimmer are the same trimmer, or the first trimmer and the second trimmer are different trimmers.

[0022] The present invention also provides a chemical mechanical polishing method, which uses a polishing pad to polish an object to be polished, and uses any one of the polishing pad dressing devices described above to dress the polishing pad before or during the polishing process.

[0023] Optionally, the following steps are included:

[0024] Using the first dresser to perform a first dressing process on the polishing pad so that the removal rate of the polishing pad meets a first preset range, and using the polishing pad after the first dressing process to perform a first stage of polishing on the polishing object;

[0025] The second connecting portion is rotated 180 degrees by the reversing drive structure to exchange the positions of the first dresser and the second dresser, the second dresser is used to perform a second dressing process on the polishing pad, and the polishing pad after the second dressing process is used to perform a second stage of polishing on the polishing object;

[0026] When the removal rate of the grinding pad drops to a second preset range, the first stage grinding is ended, and the second dressing process is performed on the grinding pad using the second dresser so that the removal rate of the grinding pad meets the first preset range, and the cutting force of the second dresser is greater than the cutting force of the first dresser;

[0027] Alternatively, when the grinding object is thinned to a preset thickness, the first stage grinding is terminated, and the second dresser is used to perform the second dressing process on the grinding pad to repair the surface state of the grinding pad, so that the surface roughness of the grinding object is reduced during the second stage grinding process, and the cutting force of the second dresser is less than the cutting force of the first dresser.

[0028] Optionally, the first dresser and the second dresser are the same dresser, and the first dresser is first used to dress the grinding pad. When the first dresser reaches a scrap state, the second connecting part is rotated 180° through the reversing drive structure to exchange the positions of the first dresser and the second dresser, and the second dresser is used to dress the grinding pad.

[0029] As described above, the grinding pad dressing device of the present invention includes a mechanical arm, a first connecting part, a reversing drive structure, a second connecting part, a first dresser and a second dresser, wherein the first connecting part is connected to the mechanical arm, the reversing drive structure is connected to the first connecting part and has a rotating output shaft on the side away from the first connecting part, the second connecting part has a first mounting surface and a second mounting surface perpendicular to each other and is connected to the rotating output shaft to rotate under the drive of the rotating output shaft, when the second connecting part rotates 180°, the positions of the first mounting surface and the second mounting surface are interchanged, the first dresser is installed on the first mounting surface through the first support and the disk surface of the first dresser is parallel to the first mounting surface, the second dresser is installed on the second mounting surface through the second support and the disk surface of the second dresser is parallel to the second mounting surface. The grinding pad dressing device of the present invention adopts a double dresser structure, and in the case of single-chamber grinding and only one mechanical arm, the interchange of the positions of the two dressers can be realized through the reversing drive structure. Using the grinding pad dressing device of the present invention, different dressers can be configured according to demand to achieve the adjustment of different surface states of the grinding pad at different stages of a grinding process. The grinding pad dressing device of the present invention can also be configured with the same dressers. When one of the dressers cannot be used, it can be switched to another dresser, which can reduce the frequency of machine maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Shown is a schematic diagram of a grinding process.

[0031] Figure 2 Shown is a schematic diagram of the polishing pad after a period of use.

[0032] Figure 3 Shown is a schematic diagram of the polishing pad dressing process.

[0033] Figure 4 Shown is a schematic diagram of an exemplary structure of the polishing pad dressing device of the present invention.

[0034] Figure 5 Shown is a schematic diagram of an exemplary structure of the polishing pad dressing device of the present invention at another viewing angle.

[0035] Component number description

[0036] 101 Grinding fluid

[0037] 102 Abrasive pad

[0038] 103 Wafer

[0039] 104 Byproduct

[0040] 105 Dresser

[0041] 201 Robotic Arm

[0042] 202 First connection

[0043] 203 Reversing drive structure

[0044] 204 Second connection

[0045] 204a First mounting surface

[0046] 204b Second mounting surface

[0047] 205 First Dresser

[0048] 206 Second Dresser

[0049] 207 first support member

[0050] 2071 First installation plate

[0051] 2072 Second mounting plate

[0052] 2073 Dresser disc angle adjustment parts

[0053] 208 second support member

[0054] 209 Pneumatic buffer DETAILED DESCRIPTION

[0055] During the chemical mechanical polishing process, factors that affect the removal rate (RR) include the polishing pad, polishing fluid, dresser and polishing conditions. In the chemical mechanical polishing process, the polishing pad is also constantly worn. The physical force field existing in the grooves and holes on the surface of the polishing pad and the large number of chemical dangling bonds existing after the surface is worn adsorb a large number of abrasive particles and waste debris from processing and grinding. The continuously accumulated particles are left in the grooves, which will reduce the mass transfer of chemical reactants and products during the polishing process, reduce the mechanical friction during the polishing process, and cause the average removal rate / surface roughness consistency of the wafer to deteriorate.

[0056] See also Figures 1 to 3 ,in, Figure 1 A schematic diagram showing a grinding process. Figure 2 This is a diagram of the polishing pad after it has been used for a period of time. Figure 3 The figure shows the schematic diagram of the polishing pad dressing process. Figure 1As shown, during the grinding process, the grinding liquid 101 is distributed on the surface of the grinding pad 102, and the wafer 103 is placed on the surface of the grinding pad 102 and is pressed down and moved (as shown by the arrow in the figure). Figure 2 As shown, after a period of use, the grooves on the surface of the polishing pad will be filled with byproducts 104. Figure 3 As shown in FIG. 1 , after being trimmed by the trimmer 105, the polishing pad 102 is removed by a certain thickness (the removal amount is shown in the figure). Figure 1-Figure 3 It can be seen that the removal rate of the polishing pad will become unstable as the polishing time increases, and the removal rate can be adjusted by dressing the polishing pad with a dresser to restore the polishing ability of the polishing pad. However, the degree of dressing of a single dresser is currently limited and cannot meet the requirements of adjusting different surface conditions of the polishing pad during a polishing process.

[0057] Specifically, as grinding progresses, the surface state of the grinding pad will gradually change. The surface state of the grinding pad can be quickly trimmed by a diamond dresser. However, while the diamond particles quickly remove waste materials, they will damage the surface of the grinding pad, causing the uniformity of the surface flatness of the grinding pad to deteriorate, thereby affecting the grinding rate and effect. In order to improve the surface state of the grinding pad during the grinding process, a diamond dresser can be used to adjust the surface state of the grinding pad in the early stage of grinding to improve the grinding efficiency, and a brush dresser can be used in the later stage of grinding to optimize the surface roughness of the wafer. However, each chamber of the existing equipment has only one dresser arm and can only be equipped with one dresser, which cannot meet the needs of high-end processes.

[0058] After extensive research, the inventor of the present invention has designed a new grinding pad dressing device, which adopts a dual dresser structure. In the case of single-chamber grinding and only one mechanical arm, the positions of the two dressers can be interchanged through a reversing drive structure, so that a suitable dresser can be selected as needed to achieve dynamic adjustment of the surface state of the grinding pad during a grinding process. The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0059] See also Figures 1 to 5 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0060] See also Figure 4 , which is a schematic diagram of an example structure of the grinding pad dressing device of the present invention, includes a robot arm 201, a first connecting part 202, a reversing drive structure 203, a second connecting part 204, a first dresser 205 and a second dresser 206, wherein the first connecting part 202 is connected to the robot arm 201, the reversing drive structure 203 is connected to the first connecting part 202, the second connecting part 204 has a first mounting surface 204a and a second mounting surface 204b that are perpendicular to each other, and the second connecting part 204 is connected to the reversing drive structure 203 so as to rotate under the drive of the reversing drive structure 203 so that the positions of the first mounting surface 204a and the second mounting surface 204b are interchanged. The first trimmer 205 is mounted on the first mounting surface 204a through a first support 207, and the disk surface of the first trimmer 205 is parallel to the first mounting surface 204a. The second trimmer 206 is mounted on the second mounting surface 204b through a second support 208, and the disk surface of the second trimmer 206 is parallel to the second mounting surface 204b.

[0061] In some embodiments, when the second connection portion 204 is driven by the reversing drive structure 203 to rotate 180°, the positions of the first mounting surface 204a and the second mounting surface 204b are interchanged.

[0062] In some embodiments, the reversing drive structure 203 has a rotation output shaft (not shown) on a side away from the first connection portion 202 , and the second connection portion 204 is connected to the rotation output shaft and rotates with the rotation of the rotation output shaft.

[0063] In some embodiments, the reversing drive structure 203 has an output gear (not shown) on the side away from the first connection part 202, and the second connection part 204 has a linkage internal gear ring meshing with the output gear. When the output gear rotates, the linkage internal gear ring rotates accordingly.

[0064] In some embodiments, the reversing drive structure 203 may be a motor, and the motor output shaft is directly connected to the second connection part 204, or the motor output shaft has the output gear, and the second connection part 204 has the linkage internal gear ring.

[0065] In some embodiments, the reversing drive structure 203 may also be a rotary cylinder, wherein the rotary cylinder is a cylinder that performs reciprocating swing within an angle range less than 360°, and is a pneumatic actuator that uses compressed air to drive the rotary output shaft to perform reciprocating rotation within a certain angle range. The rotary output shaft of the rotary cylinder may be directly connected to the second connecting portion 204, or the rotary output shaft may have the output gear, and the second connecting portion 204 may have the linkage internal gear ring.

[0066] In some embodiments, the rotary cylinder may be a blade-type rotary cylinder, which changes its swing angle through an internal stop block or an external stop block. The stop block and the cylinder body are fixed together, the blades and the rotating shaft are connected together, and the air pressure acts on the blades to drive the rotating shaft to rotate and output torque.

[0067] In some embodiments, the rotary cylinder may also be a gear-type rotary cylinder, which uses gas pressure to push the piston to drive the rack to make linear motion, and the rack drives the gear to make rotational motion, and the gear shaft outputs torque and drives the external load to swing.

[0068] See also Figure 5 , which is a schematic diagram of an exemplary structure of the polishing pad dressing device of the present invention from another perspective. In some embodiments, the rotary cylinder may be provided with a pneumatic buffer 209, which can pressurize the reverse airflow during reversal to reduce contact stress. The pneumatic buffer 209 can be implemented, for example, by drilling a threaded hole near the air inlet of the cylinder to pass into the interior of the cylinder. The gas passing area of ​​the threaded hole can be adjusted, and the size of the cylinder buffer can be adjusted by the size of the flow rate during exhaust.

[0069] Specifically, an adjustable hexagon socket screw is provided in the threaded hole. By turning the screw left and right, the aperture size of the threaded hole can be adjusted, thereby adjusting the speed of the recoil in the cylinder to avoid excessive noise and damage to the cylinder. Because when the cylinder is at the end of the stroke and the movement speed is too high, relying solely on the rebound inside the cylinder is not enough to absorb the impact force of the piston on the cylinder, which will generate a lot of noise and damage the cylinder. The present invention provides the pneumatic buffer 209 and uses the screw in the threaded hole to adjust the speed of the cylinder recoil. When the screw is turned inward, the buffering will become more obvious, and when the screw is turned outward, the buffering will become less obvious. It can be adjusted specifically as needed.

[0070] In some embodiments, the plane where the reversing drive structure 203 is located is at an angle of 45° to the horizontal plane, the first connecting portion 202 and the second connecting portion 204 are symmetrical about the reversing drive structure 203 and are both roughly isosceles right triangles, and the first mounting surface 204a and the second mounting surface 204b of the second connecting portion 204 respectively correspond to the two right-angled sides of the isosceles right triangle.

[0071] In some embodiments, both the first connection portion 202 and the second connection portion 204 have hollow portions, which is helpful in reducing component weight.

[0072] In some embodiments, the first connection portion 202 and the robotic arm 201 are detachably connected, for example, by bolts and nuts or other suitable connectors.

[0073] In some embodiments, the first trimmer 205 is connected to the first support member 207 by bolts or other suitable connectors, the second trimmer 206 is connected to the second support member 208 by bolts or other suitable connectors, the first trimmer 205 is connected to the second connecting portion 204 by bolts or other suitable connectors, and the second trimmer 206 is connected to the second connecting portion 204 by bolts or other suitable connectors.

[0074] In some embodiments, the first support member 207 includes a first mounting plate 2071, a second mounting plate 2072, and a trimmer disc angle adjustment component 2073, the first mounting plate 2071 and the second mounting plate 2072 are opposite and spaced apart, the trimmer disc angle adjustment component is located between the first mounting plate 2071 and the second mounting plate 2072 and includes a plurality of spaced connecting columns, the lengths of the plurality of connecting columns are independently adjustable. The second support member 208 may have the same structure as the first support member 207.

[0075] Specifically, the first mounting plate 2071 is connected to the dresser, and the second mounting plate 2072 is connected to the second connecting portion 204. By adjusting the lengths of the plurality of connecting columns, the disk surface of the dresser can be easily made parallel to the disk surface of the grinding pad.

[0076] Specifically, the surface of the grinding pad will change with the dressing process of the dresser. A single dresser may cause inadequate or excessive adjustment of the grinding pad, resulting in an unstable removal rate of the grinding pad on the grinding object. In addition, if the dressing time of the dresser is fixed during the use of the entire grinding pad, the grinding pad will also have an unstable removal rate of the grinding object. The grinding pad dressing device of the present invention can optimize the adjustment effect of the dresser on the surface state of the grinding pad during chemical mechanical grinding in the case of single-chamber grinding and only one robotic arm, wherein the first dresser 205 and the second dresser 207 can be configured as the same dresser according to needs, or the first dresser 205 and the second dresser 207 can be configured as different dressers to jointly adjust the surface state of the grinding pad, for example, one of them uses a diamond dresser and the other uses a brush dresser, and a suitable dresser is used as needed at different stages of the grinding process to improve production efficiency.

[0077] The present invention also provides a chemical mechanical polishing method, which uses a polishing pad to polish an object, and uses the polishing pad dressing device to dress the polishing pad before or during the polishing process.

[0078] In some embodiments, the chemical mechanical polishing method comprises the following steps:

[0079] (1) using the first dresser 205 to perform a first dressing process on the polishing pad so that the removal rate of the polishing pad meets a first preset range;

[0080] (2) performing a first-stage grinding of the grinding object using the grinding pad that has undergone the first dressing process;

[0081] (3) When the removal rate of the polishing pad drops to a second preset range, the second connection portion is rotated 180° by the reversing drive structure 203 so that the positions of the first dresser 205 and the second dresser 206 are interchanged, and the second dresser 206 is used to perform a second dressing process on the polishing pad so that the removal rate of the polishing pad meets the first preset range;

[0082] (4) performing a second-stage grinding of the grinding object using the grinding pad after the second dressing process;

[0083] The cutting force of the second dresser 206 is greater than the cutting force of the first dresser 201 .

[0084] Specifically, the chemical mechanical polishing method uses a dresser with a small cutting force to dress the surface state of the polishing pad in the early stage so that the polishing pad meets the demand for the removal rate of the polishing object. In the later stage, when the removal rate of the polishing pad for the polishing object decreases significantly, a dresser with a large cutting force is used to dress the surface state of the polishing pad so that the polishing pad can meet the demand for the removal rate of the polishing object again.

[0085] It should be pointed out that the "small cutting force" and "large cutting force" mentioned here and in the following are relative concepts. For different grinding pads, the standards of cutting force are different, and the specific numerical range of cutting force is not set here.

[0086] In some embodiments, the chemical mechanical polishing method comprises the following steps:

[0087] (1) using the first dresser 205 to perform a first dressing process on the polishing pad so that the removal rate of the polishing pad meets a first preset range;

[0088] (2) performing a first-stage grinding on the grinding object using the grinding pad that has undergone the first dressing process, and ending the first-stage grinding when the grinding object is thinned to a preset thickness;

[0089] (3) rotating the second connection portion 180° by the reversing drive structure 203 so that the positions of the first dresser 205 and the second dresser 206 are interchanged, and performing a second dressing process on the polishing pad by using the second dresser 206 to repair the surface condition of the polishing pad;

[0090] (4) performing a second-stage grinding of the grinding object using the grinding pad after the second dressing process to reduce the surface roughness of the grinding object;

[0091] The cutting force of the second dresser 206 is smaller than the cutting force of the first dresser 205 .

[0092] Specifically, in a main grinding process, the chemical mechanical grinding method uses a high-cutting force dresser such as a diamond dresser in the early stage to increase the removal rate of the grinding object, and uses a low-cutting force dresser such as a brush dresser in the later stage to repair the surface state of the grinding pad and reduce the surface roughness of the grinding object such as a wafer. Compared with the solution that the surface state of the grinding pad is easily adjusted by a single dresser, which easily leads to poor surface roughness of the grinding object in the later stage of grinding, the present invention uses a grinding pad dressing device equipped with two soft and hard dressers, which can realize dynamic dressing of the surface state of the grinding pad as the grinding process proceeds.

[0093] In some embodiments, a dresser with greater cutting force may be used at a later stage to increase the roughness of the surface of the grinding object.

[0094] In some embodiments, the chemical mechanical polishing method includes the following steps: the first dresser 205 and the second dresser 206 are the same dresser, and the first dresser 205 is first used to dress the polishing pad. When the first dresser reaches a scrap state, the second connecting part is rotated 180° through the reversing drive structure 203 to exchange the positions of the first dresser 205 and the second dresser 206, and the second dresser 206 is used to dress the polishing pad.

[0095] Specifically, the chemical mechanical polishing method does not need to be shut down for maintenance after one of the dressers cannot be used, but can be switched to another identical dresser in time through the reversing drive structure 203, thereby reducing the frequency of machine maintenance and improving production efficiency.

[0096] In some embodiments, the chemical mechanical polishing method keeps the polishing time unchanged during a polishing process, and keeps the dressing time of the polishing pad by the diamond dresser with larger cutting force unchanged, while increasing the dressing time of the polishing pad by the brush dresser with smaller cutting force, which can effectively reduce the risk of breakage and defects of the polishing object such as wafers.

[0097] In summary, the grinding pad dressing device of the present invention includes a mechanical arm, a first connecting part, a reversing drive structure, a second connecting part, a first dresser and a second dresser, wherein the first connecting part is connected to the mechanical arm, the reversing drive structure is connected to the first connecting part and has a rotating output shaft on the side away from the first connecting part, the second connecting part has a first mounting surface and a second mounting surface perpendicular to each other and is connected to the rotating output shaft to rotate under the drive of the rotating output shaft, when the second connecting part rotates 180°, the positions of the first mounting surface and the second mounting surface are interchanged, the first dresser is installed on the first mounting surface through the first support and the disk surface of the first dresser is parallel to the first mounting surface, the second dresser is installed on the second mounting surface through the second support and the disk surface of the second dresser is parallel to the second mounting surface. The grinding pad dressing device of the present invention adopts a double dresser structure, and in the case of single-chamber grinding and only one mechanical arm, the positions of the two dressers can be interchanged through the reversing drive structure. The grinding pad dressing device of the present invention can be configured with different dressers according to needs to achieve the adjustment of different surface states of the grinding pad at different stages of a grinding process. The polishing pad dressing device of the present invention can also be equipped with the same dresser. When one dresser cannot be used, it can be switched to another dresser, which can reduce the frequency of machine maintenance. Therefore, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0098] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A grinding pad dressing device, characterized in that: include: Robotic arm; A first connection part, connected to the robotic arm; A reversing drive structure connected to the first connecting portion; A second connection portion, having a first mounting surface and a second mounting surface perpendicular to each other, wherein the second connection portion is connected to the reversing drive structure so as to rotate under the drive of the reversing drive structure so that the positions of the first mounting surface and the second mounting surface are interchanged; A first trimmer is mounted on the first mounting surface via a first support member, and a disk surface of the first trimmer is parallel to the first mounting surface; The second trimmer is mounted on the second mounting surface via a second support member, and the disk surface of the second trimmer is parallel to the second mounting surface.

2. The polishing pad dressing device according to claim 1, characterized in that: When the second connecting portion is driven by the reversing drive structure to rotate 180°, the positions of the first mounting surface and the second mounting surface are interchanged.

3. The polishing pad dressing device according to claim 1, characterized in that: The reversing drive structure has a rotating output shaft, and the second connecting portion is connected to the rotating output shaft; or the reversing drive structure has an output gear, and the second connecting portion has a linkage internal gear ring meshing with the output gear.

4. The polishing pad dressing device according to claim 1, characterized in that: The reversing drive structure includes a motor or a rotary cylinder.

5. The polishing pad dressing device according to claim 4, characterized in that: The rotary cylinder is provided with a pneumatic buffer.

6. The polishing pad dressing device according to claim 1, characterized in that: The first support member includes a first mounting plate, a second mounting plate and a trimmer disk angle adjustment component, the first mounting plate and the second mounting plate are opposite to each other and are spaced apart, the trimmer disk angle adjustment component is located between the first mounting plate and the second mounting plate and includes a plurality of spaced apart connecting columns, the lengths of the plurality of connecting columns are independently adjustable; the second support member adopts the same structure as the first support member.

7. The polishing pad dressing device according to claim 1, characterized in that: The first trimmer and the second trimmer are the same trimmer, or the first trimmer and the second trimmer are different trimmers.

8. A chemical mechanical polishing method, characterized in that: The grinding object is ground with a grinding pad, and before or during the grinding, the grinding pad is trimmed with a grinding pad trimming device as described in any one of claims 1 to 7.

9. The chemical mechanical polishing method according to claim 8, characterized in that: The following steps are involved: Using the first dresser to perform a first dressing process on the polishing pad so that the removal rate of the polishing pad meets a first preset range, and using the polishing pad after the first dressing process to perform a first stage of polishing on the polishing object; The second connecting portion is rotated 180 degrees by the reversing drive structure to exchange the positions of the first dresser and the second dresser, the second dresser is used to perform a second dressing process on the polishing pad, and the polishing pad after the second dressing process is used to perform a second stage of polishing on the polishing object; When the removal rate of the grinding pad drops to a second preset range, the first stage grinding is ended, and the second dressing process is performed on the grinding pad using the second dresser so that the removal rate of the grinding pad meets the first preset range, and the cutting force of the second dresser is greater than the cutting force of the first dresser; Alternatively, when the grinding object is thinned to a preset thickness, the first stage grinding is ended, and the second dresser is used to perform the second dressing process on the grinding pad to repair the surface state of the grinding pad, so that the surface roughness of the grinding object is reduced during the second stage grinding process, and the cutting force of the second dresser is less than the cutting force of the first dresser.

10. The chemical mechanical polishing method according to claim 8, characterized in that: The first dresser and the second dresser are the same dresser, and the first dresser is first used to dress the grinding pad. When the first dresser reaches a scrap state, the second connecting part is rotated 180° through the reversing drive structure to exchange the positions of the first dresser and the second dresser, and the second dresser is used to dress the grinding pad.

Images