Retaining ring finishing device, chemical mechanical polishing unit and control method thereof, and chemical mechanical polishing apparatus

Abstract

The embodiment of the application provides a retaining ring trimming device, a chemical mechanical polishing unit and a control method thereof and a chemical mechanical polishing equipment, the device comprising a base, a trimming disc, a detection member and a controller; the trimming disc is arranged on one side of the base and is used for grinding and trimming the ground surface of the retaining ring after the polishing head drives the retaining ring to move to the ground surface of the retaining ring abutting against the side of the trimming disc away from the base, and in the process of the polishing head driving the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring; the detection member is arranged on the base and is used for detecting the shape data of the ground surface of the retaining ring in the process of the trimming disc grinding and trimming the retaining ring; and the controller is used for controlling the polishing head to stop driving the retaining ring to rotate relative to the trimming disc after it is determined that the shape data meets the target condition for indicating that the shape of the ground surface of the retaining ring is normal, so that the grinding and trimming of the retaining ring by the trimming disc is ended. The scheme can save resources.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of wafer polishing, and particularly relate to a retaining ring trimming device, a chemical mechanical polishing unit and a control method thereof, and a chemical mechanical polishing apparatus. BACKGROUND

[0002] Chemical mechanical polishing (CMP) is a technique for polishing a wafer, which polishes a wafer surface by using a mechanical and chemical combination to realize planarization of the wafer surface topography.

[0003] The CMP can generally be realized by a CMP apparatus, which includes a polishing head and a retaining ring. In the process of polishing a wafer by using the CMP, the wafer can be first adsorbed and installed on the polishing head so as to be located in a space surrounded by the retaining ring, and then the polishing head can drive the wafer to polish. In the polishing process, the retaining ring can limit the wafer and also can affect the stress state of the wafer edge, so that the polishing effect of the wafer is better.

[0004] However, the surface state of the retaining ring has a significant influence on the polishing effect of the wafer. For example, after a period of polishing operation by using a CMP apparatus including a retaining ring with uniform thickness, different positions on the same radius of the retaining ring will generally have different degrees of wear, so that the retaining ring is in a state of non-uniform thickness. In order to avoid the influence of the surface state of the retaining ring on the polishing effect of the wafer as much as possible, the retaining ring is currently usually replaced frequently, so that resources are wasted. SUMMARY

[0005] Therefore, embodiments of the present application provide a retaining ring trimming device, a chemical mechanical polishing unit and a control method thereof, and a chemical mechanical polishing apparatus to at least partially solve the above problems.

[0006] According to a first aspect of the embodiments of the present application, a retaining ring trimming device is provided, comprising a base, a trimming disc, a detection member and a controller; the trimming disc is arranged on one side of the base, and is used to grind the ground surface of the retaining ring when the polishing head of a chemical mechanical polishing unit drives the retaining ring to move to abut the ground surface of the retaining ring away from the polishing head against the side of the trimming disc away from the base, and in the process of rotating the retaining ring relative to the trimming disc around the axis of the retaining ring by the polishing head; the detection member is arranged on the base and is electrically connected with the controller, and is used to detect the shape data of the ground surface of the retaining ring in the process of grinding the retaining ring by the trimming disc, and send the shape data to the controller; the controller is used to receive the shape data, and control the polishing head to stop driving the retaining ring to rotate relative to the trimming disc to end the grinding of the retaining ring by the trimming disc after determining that the shape data meets a target condition for indicating that the shape of the ground surface of the retaining ring is normal.

[0007] According to a second aspect of the embodiments of the present application, a chemical mechanical polishing unit is provided, which is used in cooperation with the retaining ring trimming device of the first aspect described above, and comprises a retaining ring and a polishing head; the retaining ring is connected to one side of the polishing head; the polishing head is used to drive the retaining ring to move to abut the ground surface of the retaining ring away from the polishing head against the side of the trimming disc away from the base, and drive the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring to grind the ground surface of the retaining ring, and is also used to connect a wafer to make the wafer located in the area surrounded by the retaining ring, and drive the wafer to be chemically mechanically polished.

[0008] According to a third aspect of the embodiments of the present application, a chemical mechanical polishing unit control method is provided, which is used to control the chemical mechanical polishing unit of the second aspect described above, and comprises: when the chemical mechanical polishing unit is not connected with a wafer, controlling the polishing head of the chemical mechanical polishing unit to drive the retaining ring to move to abut the ground surface of the retaining ring away from the polishing head against the side of the trimming disc away from the base; and controlling the polishing head to drive the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring to grind the ground surface of the retaining ring.

[0009] According to a fourth aspect of the embodiments of the present application, a chemical mechanical polishing device is provided, comprising a polishing disc, a liquid supply member, and the chemical mechanical polishing unit according to the second aspect; the polishing disc is provided with a polishing pad on one side; the liquid supply member is configured to supply polishing liquid to the side of the polishing pad away from the polishing disc; the polishing head is further configured to connect a wafer so that the wafer is located in the area surrounded by the retaining ring, and the polished layer of the wafer is abutted on the polishing pad, and the wafer is driven to move relative to the polishing pad so as to perform chemical mechanical polishing on the wafer.

[0010] According to the retaining ring trimming device provided by the embodiments of the present application, when the chemical mechanical polishing unit is not adsorbed with a wafer, the polishing head can be controlled to drive the retaining ring to move to the ground surface of the retaining ring abutting on the side of the trimming disc away from the base, and the polishing head can be controlled to drive the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring, so that the trimming disc performs grinding trimming on the ground surface of the retaining ring. During the grinding trimming, the detection member can detect the shape data of the ground surface of the retaining ring and send the shape data to the controller. After receiving the shape data, if the controller determines that the shape data meets the target condition (i.e. the condition for indicating that the shape of the ground surface of the retaining ring is normal), the polishing head is controlled to stop driving the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring, so that the grinding trimming of the retaining ring is ended. Thus, compared with the solution of frequently replacing the retaining ring to replace the retaining ring as much as possible before the shape of the ground surface of the retaining ring is abnormal, the retaining ring trimming device in the present application can trim the ground surface of the retaining ring and stop trimming when the shape of the ground surface of the retaining ring is normal, so that the service life of the retaining ring is longer and the replacement frequency of the retaining ring is reduced, and therefore, resources can be saved. BRIEF DESCRIPTION OF DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the embodiments of the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0012] Figure 1 is a structural schematic diagram of a chemical mechanical polishing unit according to an embodiment of the present application;

[0013] Figure 2 is a structural schematic diagram of a retaining ring trimming device according to an embodiment of the present application;

[0014] Figure 3 is a structural schematic diagram of a base according to an embodiment of the present application;

[0015] Figure 4 is a structural schematic diagram of a trimming disc according to an embodiment of the present application;

[0016] Figure 5 is a structural schematic diagram of a cleaning assembly according to an embodiment of the present application;

[0017] Figure 6 is a side view of a cleaning assembly according to another embodiment of the present application;

[0018] Figure 7 is a working state schematic diagram of a retaining ring trimming device according to an embodiment of the present application;

[0019] Figure 8 is a working state schematic diagram of a retaining ring trimming device according to another embodiment of the present application; Figure 7 is an enlarged view of part A in

[0020] Figure 9 is a working state schematic diagram of a retaining ring trimming device according to another embodiment of the present application;

[0021] Figure 10 is an enlarged view of part B in Figure 9

[0022] Figure 11 is a working state schematic diagram of a retaining ring trimming device according to another embodiment of the present application;

[0023] Figure 12 is an enlarged view of part C in Figure 11

[0024] Figure 13 is a flow chart of a chemical mechanical polishing unit control method according to an embodiment of the present application.

[0025] BRIEF DESCRIPTION OF DRAWINGS

[0026] 1, polishing head; 2, retaining ring; 3, air film; 4, base; 41, baffle; 42, chamber; 43, second nozzle; 5, trimming disc; 51, carrier disc; 511, detection opening; 52, trimming block; 6, detection piece; 7, cleaning assembly; 71, connecting shaft; 711, first cantilever; 72, cleaning brush; 721, brush head; 7211, first head; 7212, second head; 722, brush rod; 73, first nozzle; 8, wafer supporting ring; 81, second cantilever; 82, avoiding opening. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the drawings.

[0028] ​​In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0029] The retaining ring dressing device provided in the embodiment of the present application is described in detail below with reference to the accompanying drawings.

[0030] The embodiment of the present application provides a retaining ring trimming device, which is used to trim the retaining ring 2 in a chemical mechanical polishing unit. Figure 1 Schematic diagram of the structure of a chemical mechanical polishing unit according to an embodiment of the present application. Figure 1 As shown, the chemical mechanical polishing unit includes a polishing head 1, a retaining ring 2 and a wafer connector (hereinafter described as an air film 3 as an example of the wafer connector), the retaining ring 2 is connected to one side of the polishing head 1, and the air film 3 is arranged in the space surrounded by the retaining ring 2. The air film 3 is connected to the polishing head 1. During the process of polishing the wafer using the chemical mechanical polishing unit, the air film 3 can be first driven by the polishing head 1 to move to one side of the wafer and adsorb the wafer so that the wafer is mounted on the polishing head 1 and the wafer is located in the space surrounded by the retaining ring 2. Then the polishing head 1 can drive the wafer to polish the side of the wafer away from the air film 3. During the polishing process, the retaining ring 2 can limit the wafer and affect the stress state of the edge of the wafer, so as to achieve a better polishing effect of the wafer.

[0031] Figure 2 Schematic diagram of the structure of a retaining ring trimming device according to an embodiment of the present application. Figure 2 As shown, the retaining ring dressing device includes: a base 4, a dressing disk 5, a detection member 6 and a controller.

[0032] The dressing disk 5 is arranged on one side of the base 4, and is used to grind and dress the ground surface of the retaining ring 2 after the polishing head 1 of the chemical mechanical polishing unit drives the retaining ring 2 to move until the ground surface of the retaining ring 2 away from the polishing head 1 abuts against the side of the dressing disk 5 away from the base 4, and in the process of the polishing head 1 driving the retaining ring 2 to rotate around the axis of the retaining ring 2 relative to the dressing disk 5. Optionally, in the process of the dressing disk 5 grinding and dressing the ground surface of the retaining ring 2, the polishing head 1 can apply a certain pressure in the direction close to the dressing disk 5.

[0033] The detection member 6 is arranged on the base 4 and electrically connected to the controller, and is configured to detect the shape data of the ground surface of the retaining ring 2 during the grinding and trimming of the retaining ring 2 by the trimming disc 5, and send the shape data to the controller.

[0034] The controller is configured to receive the shape data, and when it is determined that the shape data satisfies a target condition for indicating that the shape of the ground surface of the retaining ring 2 is normal, control the polishing head 1 to stop driving the retaining ring 2 to rotate relative to the trimming disc 5, so that the grinding and trimming of the retaining ring 2 by the trimming disc 5 is ended.

[0035] The target condition is set according to actual needs, for example, the target condition can be used to indicate that the ground surface of the retaining ring 2 is parallel to the side surface of the retaining ring 2 away from the ground surface, or the target condition can be used to indicate that the distance between the ground surface and the side surface of the retaining ring 2 away from the ground surface gradually increases or decreases from inside to outside, and the embodiments of the present application do not make any limitation in this regard.

[0036] In the embodiments of the present application, when the chemical mechanical polishing unit does not adsorb the wafer, the polishing head 1 can be controlled to drive the retaining ring 2 to move to the state that the ground surface of the retaining ring 2 abuts against the side surface of the trimming disc 5 away from the base 4, and the polishing head 1 can be controlled to drive the retaining ring 2 to rotate relative to the trimming disc 5 around the axis of the retaining ring 2, so that the trimming disc 5 grinds and trims the ground surface of the retaining ring 2. During the grinding and trimming, the detection member 6 can detect the shape data of the ground surface of the retaining ring 2 and send the shape data to the controller. After receiving the shape data, the controller can determine whether the shape data satisfies the target condition (i.e. the condition for indicating that the shape of the ground surface of the retaining ring 2 is normal), and when it is determined that the shape data satisfies the target condition, the controller can control the polishing head 1 to stop driving the retaining ring 2 to rotate relative to the trimming disc 5 around the axis of the retaining ring 2, so that the grinding and trimming of the retaining ring 2 is ended. Thus, compared with the solution of frequently replacing the retaining ring 2 to replace the retaining ring 2 as soon as possible before the shape of the ground surface of the retaining ring 2 is abnormal, the retaining ring trimming device in the present application can trim the ground surface of the retaining ring 2, and stop trimming when the shape of the ground surface of the retaining ring 2 is normal, so that the service life of the retaining ring 2 is longer, the replacement frequency of the retaining ring 2 is reduced, and therefore, resources can be saved.

[0037] In addition, the reduction of the replacement frequency of the retaining ring 2 can also make the stability of the flatness of the wafer after chemical mechanical polishing better, and can also reduce the cost.

[0038] In a possible implementation manner, as shown in Figure 2 and Figure 3 the base 4 is connected with a driving member (such as a motor or an air cylinder, etc.), and the driving member is configured to drive the base 4 to move in a direction perpendicular to the disc surface of the trimming disc 5.

[0039] In one specific embodiment, the base 4 is horizontally placed, the trimming disc 5 is located above the base 4, the base 4 can have a down position and an up position, the up position of the base 4 is higher than the down position, the base 4 is in the down position in the initial state of the retaining ring trimming device, before the grinding and trimming of the ground surface of the retaining ring 2, the base 4 can be driven by the driving member to move upward in the direction perpendicular to the disc surface of the trimming disc 5, so that the base 4 is in the up position, facilitating the abutment of the retaining ring 2 driven by the polishing head 1 and the trimming disc 5, after the grinding and trimming of the ground surface of the retaining ring 2, the base 4 can be driven by the driving member to move downward in the direction perpendicular to the disc surface of the trimming disc 5, so that the base 4 returns to the down position, facilitating the separation of the retaining ring 2 driven by the polishing head 1 and the trimming disc 5, the driving of the base 4 from the up position to the down position by the driving member can be before, after or at the same time as the movement of the retaining ring 2 driven by the polishing head 1 away from the trimming disc 5, which is not limited in the embodiments of the present application.

[0040] In the embodiments of the present application, before and after the grinding and trimming of the ground surface of the retaining ring 2 by the retaining ring trimming device, the base 4 can be adjusted by the driving member to move in the direction perpendicular to the disc surface of the trimming disc 5, so that the trimming disc 5 can be driven by the base 4 to move to a position facilitating the abutment or separation of the retaining ring 2 on the polishing head 1 and the trimming disc 5, to facilitate the abutment or separation of the retaining ring 2 driven by the polishing head 1 and the trimming disc 5.

[0041] In one possible implementation, as shown in Figure 2 and Figure 3 , the side of the base 4 close to the trimming disc 5 is connected with a surrounding plate 41, the connection between the surrounding plate 41 and the base 4 can be fixed connection, integral connection or detachable connection, etc., the surrounding plate 41 is perpendicular to the disc surface of the trimming disc 5, and the trimming disc 5 is located in the space surrounded by the surrounding plate 41.

[0042] Therefore, the setting of the surrounding plate 41 can reduce the possibility of the debris and impurities of the retaining ring 2 falling outside the retaining ring trimming device when the retaining ring 2 is ground and trimmed by the trimming disc 5, and improve the neatness of the environment around the retaining ring trimming device.

[0043] In one possible implementation, as shown in Figure 2 and Figure 4 , the trimming disc 5 comprises a bearing disc 51 and at least one trimming block 52.

[0044] The bearing disc 51 is connected with the base 4, and the connection can be fixed connection, integral connection or detachable connection, etc. The shape of the bearing disc 51 is a circular disc, that is, the opposite two sides of the bearing disc 51 are circular surfaces. One circular surface of the bearing disc 51 abuts against the base 4. When the dressing disc 5 grinds and dresses the retaining ring 2, the axis of the bearing disc 51 coincides with the axis of the retaining ring 2. Based on this, the detection piece 6 is arranged at a position of the base 4 close to the bearing disc 51. A detection opening 511 is formed in the bearing disc 51 and penetrates the bearing disc 51 along the thickness direction of the bearing disc 51, so as to detect the shape of the ground surface of the retaining ring 2 during grinding and dressing of the retaining ring 2.

[0045] The dressing block 52 is connected to the circular surface of the bearing disc 51 away from the base 4. If a plurality of dressing blocks 52 are arranged, the plurality of dressing blocks 52 can be uniformly arranged along the circumferential direction of the bearing disc 51. The dressing block 52 is used to grind and dress the ground surface of the retaining ring 2 after the polishing head 1 drives the retaining ring 2 to move to the position where the ground surface of the retaining ring 2 abuts against the side of the dressing block 52 away from the bearing disc 51, and during the process that the polishing head 1 drives the retaining ring 2 to rotate relative to the dressing block 52 around the axis of the retaining ring 2.

[0046] For a process with relatively low requirement for impurity interference, the material of the side of the dressing block 52 used to abut against the ground surface of the retaining ring 2 can be inorganic ceramic frosted material. For a process with high requirement for impurity interference, the material of the side of the dressing block 52 used to abut against the ground surface of the retaining ring 2 can be hard organic material similar to the material of the polishing pad, for example, the material of the side of the dressing block 52 used to abut against the ground surface of the retaining ring 2 can be PPS (polyphenylene sulfide) or PEEK (polyether ether ketone), etc. The embodiments of the present application do not limit this. The dressing amount of the dressing block 52 to the ground surface of the retaining ring 2 is generally small, for example, 20 to 30 μm, etc. The shape of the dressing block 52 can be set according to the above target condition. For example, the target condition is used to indicate that the distance between the ground surface and the side of the retaining ring 2 away from the ground surface gradually increases from inside to outside, and the side of the dressing block 52 used to abut against the ground surface of the retaining ring 2 is arranged to be inclined from inside to outside and from the side away from the bearing disc 51 to the side close to the bearing disc 51.

[0047] Optionally, the dressing block 52 is detachably connected with the bearing disc 51, so that different shapes of the dressing block 52 can be replaced according to the target condition, thereby improving the applicability of the retaining ring dressing device.

[0048] Therefore, by arranging the bearing disc 51 and the dressing block 52, the bearing disc 51 can support the retaining block, that is, the overall structure of the dressing disc 5 has certain rigidity and stability. The dressing block 52 can grind and dress the ground surface of the retaining ring 2, thereby prolonging the service life of the retaining ring and reducing the cost.

[0049] In a possible implementation, the shape of the retaining ring 2 is a circular ring, and the same detection member 6 of the retaining ring 2 detects the same shape data, which includes the distances between the detection head of the detection member 6 and the plurality of position points on any ring width line of the ground surface of the retaining ring 2, wherein the ring width line of the ground surface of the retaining ring 2 is a line segment on the ground surface with a radius.

[0050] In a specific embodiment, the detection member 6 can be an optical distance sensor, which is configured to emit white light from the detection head of the detection member 6 to any ring width line of the ground surface of the retaining ring 2 through the detection opening 511, so as to measure the distances between the detection head of the detection member 6 and the plurality of position points on the ring width line of the ground surface of the retaining ring 2 by white light interference principle, and then obtain the shape data including the plurality of distances, which is related to the shape of the ground surface of the retaining ring 2. For example, if the ground surface of the retaining ring 2 is parallel to the side surface of the retaining ring 2 away from the ground surface, the plurality of distances included in the shape data obtained at this time are almost the same. If the distance between the ground surface and the side surface of the retaining ring 2 away from the ground surface gradually increases or decreases from the inside to the outside, the plurality of distances included in the shape data obtained at this time are almost different.

[0051] Therefore, the detection member 6 can obtain the shape data of the ground surface of the retaining ring 2 by detecting the distances between the detection head of the detection member 6 and different position points on the same ring width line of the ground surface of the retaining ring 2, which is simple and convenient, and has low cost.

[0052] In a possible implementation, as shown in Figure 2 and Figure 5 The retaining ring finishing device further comprises a cleaning assembly 7 connected to the base 4, which is configured to clean the dust attached to the ground surface of the retaining ring 2 and / or the debris of the retaining ring 2 and other impurities after the grinding finishing of the retaining ring 2 by the finishing disc 5, and / or clean the dust attached to the side surface of the carrier disc 51 away from the base 4 and the side surface of the finishing block 52 away from the base 4 and other impurities.

[0053] In a specific embodiment, after the dressing disk 5 finishes grinding and dressing the retaining ring 2, the controller can control the cleaning component 7 to perform a cleaning operation, so that the cleaning component 7 cleans the impurities attached to the ground surface of the retaining ring 2, and / or cleans the impurities attached to the side of the carrier plate 51 away from the base 4 and the side of the dressing block 52 away from the base 4. Thus, the cleaning component 7 cleans the impurities attached to the ground surface of the retaining ring 2, which can reduce the damage caused to the wafer by the impurities attached to the ground surface of the retaining ring 2 during the polishing of the wafer (for example, direct damage to the wafer caused by impurities attached to the ground surface of the retaining ring 2 during the polishing of the wafer, and for example The cleaning component 7 cleans the impurities attached to the side of the supporting plate 51 away from the base 4 and the side of the dressing block 52 away from the base 4, so as to clean the dressing plate 5 so as to ensure the grinding effect of the dressing plate 5 when grinding other retaining rings 2 in the future.

[0054] In one possible implementation, Figure 2 、 Figure 3 and Figure 5 As shown, a chamber 42 is provided on the side of the base 4 close to the trimming plate 5, and the bottom surface of the chamber 42 (the bottom surface of the chamber 42 specifically refers to Figure 3The cleaning assembly 7 is perpendicular to the axial direction of the carrier disc 51 (i.e. the direction perpendicular to the bottom surface of the cavity 42), and comprises a connecting shaft 71 and at least one cleaning brush 72. The connecting shaft 71 is located in the cavity 42, and is slidingly connected to the base 4 along the axial direction of the carrier disc 51 (i.e. the direction perpendicular to the bottom surface of the cavity 42), and is rotatably connected to the base 4 around the axial direction of the carrier disc 51. The cleaning brush 72 is slidingly connected to the connecting shaft 71 in the direction towards the bottom surface of the cavity 42 and away from the bottom surface of the cavity 42, and if the cleaning brush 72 is provided with a plurality of cleaning brushes, the plurality of cleaning brushes 72 are uniformly distributed along the circumferential direction of the carrier disc 51. The controller is configured to, after the grinding and dressing of the retaining ring 2 by the dressing disc 5 is completed, control the polishing head 1 to separate the retaining ring 2 from the dressing block 52 according to the received first control instruction, control the connecting shaft 71 to move the cleaning brush 72 away from the bottom surface of the base 4, and control the cleaning brush 72 to slide away from the connecting shaft 71 and the bottom surface of the cavity 42, so that the cleaning brush 72 slides relative to the connecting shaft 71 to a position where at least part of the brush head 721 of the cleaning brush 72 is located between the retaining ring 2 and the dressing disc 5, and is further configured to, after at least part of the brush head 721 is located between the retaining ring 2 and the dressing disc 5, control the connecting shaft 71 to rotate the cleaning brush 72 relative to the base 4 according to the received second control instruction, and control the cleaning brush 72 to reciprocally slide relative to the connecting shaft 71.

[0055] In one specific embodiment, in combination with the above-mentioned "the base 4 is horizontally placed, the dressing disc 5 is located above the base 4, and the base 4 can have a down position and an up position", the connecting shaft 71 can have at least a down position and a mid position relative to the base 4, the mid position of the connecting shaft 71 is higher than the down position relative to the base 4, and the cleaning brush 72 can have a down position and an up position relative to the connecting shaft 71, the up position of the cleaning brush 72 is higher than the down position relative to the connecting shaft 71. In the initial state of the retaining ring dressing device and during the grinding and dressing of the retaining ring 2 by the retaining ring dressing device, the connecting shaft 71 is in the down position, and the cleaning brush 72 is in the down position. Based on this:

[0056] After the grinding and finishing of the retaining ring 2 by the finishing disc 5 is completed, that is, after the polishing head 1 stops driving the retaining ring 2 to rotate relative to the finishing disc 5 around the axis of the retaining ring 2, the retaining ring finishing device can perform a cleaning operation. Specifically, the controller receives a first control instruction, so that the controller can control the polishing head 1 to drive the retaining ring 2 to move away from the finishing block 52, and control the connecting shaft 71 to drive the cleaning brush 72 to move away from the bottom surface of the base 4 relative to the base 4 until the connecting shaft 71 is in the mid position. The controller also controls the cleaning brush 72 to slide away from the connecting shaft 71 and away from the bottom surface of the chamber 42, so that the cleaning brush 72 is in the up position, and the cleaning brush 72 is slid relative to the connecting shaft 71 until at least part of the brush head 721 included in the cleaning brush 72 is located between the retaining ring 2 and the finishing disc 5. After at least part of the brush head 721 included in the cleaning brush 72 is located between the retaining ring 2 and the finishing disc 5, the controller can also receive a second control instruction, so that the controller can control the connecting shaft 71 to drive the cleaning brush 72 to rotate relative to the base 4, and can control the cleaning brush 72 to reciprocally slide relative to the connecting shaft 71. Thus, the brush head 721 of the cleaning brush 72 can sweep and clean the impurities attached to the ground surface of the retaining ring 2, and the impurities attached to the side surface of the bearing disc 51 away from the base 4 and the side surface of the finishing block 52 away from the base 4.

[0057] Therefore, by arranging the sliding connection and rotational connection of the connecting shaft 71 relative to the base 4, and the sliding connection of the cleaning brush 72 relative to the connecting shaft 71, the brush head 721 of the cleaning brush 72 can simultaneously clean the retaining ring 2 and the finishing disc 5 during the cleaning process. In addition, the connecting shaft 71 drives the brush head 721 of the cleaning brush 72 to rotate relative to the base 4, and the cleaning brush 72 reciprocally slides relative to the connecting shaft 71, which improves the cleaning effect.

[0058] In a possible implementation, as shown in Figure 2 and Figure 5 The cleaning brush 72 further includes a brush rod 722. The brush rod 722 is in the shape of a straight rod. The distance between the first end of the brush rod 722 and the bottom surface of the chamber 42 is less than the distance between the second end of the brush rod 722 and the bottom surface of the chamber 42. The first end of the brush rod 722 is slidably connected to the connecting shaft 71 along the length direction of the brush rod 722. For example, the first end of the brush rod 722 is slidably connected to the first cantilever 711 along the length direction of the brush rod 722, so as to achieve the sliding connection of the cleaning brush 72 relative to the connecting shaft 71 in the direction close to the connecting shaft 71 and close to the bottom surface of the chamber 42, or in the direction away from the connecting shaft 71 and away from the bottom surface of the chamber 42. The second end of the brush rod 722 is connected to the brush head 721. The connection manner can be integral connection, detachable connection, fixed connection, or the like.

[0059] Therefore, the sliding connection of the cleaning brush 72 relative to the connecting shaft 71 can be achieved by tilting the brush rod 722 of the cleaning brush 72 relative to the bottom surface of the cavity 42, which is simple in structure and saves cost.

[0060] In a possible implementation, as shown in Figure 2 、 Figure 5 and Figure 6 , the brush head 721 includes a first head 7211 and a second head 7212; the first head 7211 and the second head 7212 are arranged in a direction perpendicular to the bottom surface of the base 4, and the first head 7211 is farther away from the bottom surface of the base 4 than the second head 7212; when at least part of the brush head 721 is located between the retaining ring 2 and the trimming disc 5, at least part of the bristles of the first head 7211 abut against the ground surface of the retaining ring 2, and at least part of the bristles of the second head 7212 abut against the side of the bearing disc 51 away from the base 4 and / or the side of the trimming block 52 away from the base 4.

[0061] It should be noted that the parts of the brush rod 722 used for connecting the first head 7211 and the second head 7212 can be independent of each other or can be an integral whole, and the embodiments of the present application do not limit this.

[0062] Therefore, the ground surface of the retaining ring 2 and the trimming disc 5 can be cleaned simultaneously by the first head 7211 and the second head 7212 respectively, thereby improving the cleaning efficiency.

[0063] Optionally, when at least part of the brush head 721 is located between the retaining ring 2 and the trimming disc 5, the first head 7211 can also abut in the groove between the air film 3 and the retaining ring 2 and / or in the gap of the air film 3, etc., so as to increase the cleaning range of the cleaning brush 72.

[0064] In a possible implementation, as shown in Figure 2 and Figure 3 , the cleaning assembly 7 further includes a first nozzle 73; the first nozzle 73 is arranged on the side of the base 4 close to the trimming disc 5, and is used for spraying liquid (such as polishing liquid and / or high-purity water, etc.) to the trimming disc 5 when the cleaning assembly 7 cleans the impurities attached to the side of the bearing disc 51 away from the base 4 and the side of the trimming block 52 away from the base 4, so as to optimize the cleaning effect.

[0065] In a possible implementation, as shown in Figure 2 and Figure 5As shown, the retaining ring trimming device further comprises a circular wafer receiving ring 8; the axis of the wafer receiving ring 8 is perpendicular to the bottom surface of the cavity 42, the wafer receiving ring 8 is connected to the connecting shaft 71, for example, the wafer receiving ring 8 can be fixedly connected to the connecting shaft 71 through the second cantilever 81, the wafer receiving ring 8 is used for receiving the wafer, and the wafer receiving ring 8 is provided with a clearance 82 for avoiding the sliding path of the cleaning brush 72 relative to the connecting shaft 71, the clearance 82 can disconnect the wafer receiving ring 8, for example, one cleaning brush 72 is arranged at each clearance 82 of the wafer receiving ring 8, and the embodiments of the present application are not limited thereto.

[0066] In one specific embodiment, in combination with the above-mentioned "the base 4 is horizontally placed, the trimming disc 5 is located above the base 4, the base 4 can have a down position and an up position, the connecting shaft 71 can have at least a down position and a mid position relative to the base 4, and the cleaning brush 72 can have a down position and an up position relative to the connecting shaft 71", the connecting shaft 71 can further have an up position relative to the base 4, the up position of the connecting shaft 71 is higher than the mid position relative to the base 4, and based thereon:

[0067] When the retaining ring trimming device does not perform grinding trimming on the retaining ring 2 and does not perform cleaning operation after grinding trimming, the base 4 can be adjusted to the up position, the connecting shaft 71 can be adjusted to the mid position relative to the base 4, so that the wafer receiving ring 8 is located at a higher position relative to the base 4, and the cleaning brush 72 can be adjusted to the down position relative to the connecting shaft 71, then the wafer can be unloaded from the polishing head 1 to the wafer receiving ring 8 by the polishing head 1, or the wafer can be taken away from the wafer receiving ring 8 by the polishing head 1, so that the wafer is mounted on the polishing head 1; the base 4 can also be adjusted to the up position, the connecting shaft 71 can be adjusted to the up position relative to the base 4, so that the wafer receiving ring 8 is located at the highest position relative to the base 4, and the cleaning brush 72 can be adjusted to the down position relative to the connecting shaft 71, then the wafer can be taken or placed on the wafer receiving ring 8 by the mechanical hand when the retaining ring trimming device does not perform grinding trimming on the retaining ring 2 and does not perform cleaning operation after grinding trimming.

[0068] Therefore, by arranging the wafer receiving ring 8, the retaining ring trimming device provides a wafer placing position for the wafer turnover, improves the applicability of the retaining ring trimming device, and the retaining ring trimming device can be made by modifying the equipment for placing the wafer, which is convenient for manufacturing, reduces the cost, and improves the manufacturing efficiency.

[0069] In addition, by arranging the wafer receiving ring 8 and the cleaning brush 72 to be connected to the connecting shaft 71, the connecting shaft 71 can drive the wafer receiving ring 8 and the cleaning brush 72 to move relative to the base 4 at the same time. Compared with the structure in which the wafer receiving ring 8 and the cleaning brush 72 are driven to move relative to the base 4 independently, the structure in the present application in which the wafer receiving ring 8 and the cleaning brush 72 are driven to move relative to the base 4 is the connecting shaft 71, which is simple in structure and improves the efficiency of driving the wafer receiving ring 8 and the cleaning brush 72 to move relative to the base 4.

[0070] In a possible implementation, as shown in Figure 2 and Figure 3 , the base 4 is further provided with a second nozzle 43; the second nozzle 43 is located on the bottom surface of the cavity 42 and is used to spray liquid (such as polishing liquid and / or high-purity water, etc.) to the wafer when the wafer is placed on the wafer receiving ring 8, so as to flush the wafer.

[0071] Based on the above-mentioned retaining ring trimming device, for example, when the polishing head 1 places the wafer w on the wafer receiving ring 8 or the polishing head 1 takes the wafer w from the wafer receiving ring 8, the retaining ring trimming device is in the state as shown in Figure 7 and Figure 8 ; when the retaining ring trimming device grinds and trims the retaining ring 2, the retaining ring trimming device is in the state as shown in Figure 9 and Figure 10 ; when the retaining ring trimming device cleans the retaining ring 2 and the trimming disc 5, the retaining ring trimming device is in the state as shown in Figure 11 and Figure 12 .

[0072] The present application also provides a chemical mechanical polishing unit for use in cooperation with the above-mentioned retaining ring trimming device, as shown in Figure 1 , the chemical mechanical polishing unit comprises the retaining ring 2 and the polishing head 1; the retaining ring 2 is connected to one side of the polishing head 1; the polishing head 1 is used to drive the retaining ring 2 to move to abut the ground surface of the retaining ring 2 away from the polishing head 1 against the side of the trimming disc 5 away from the base 4, and to drive the retaining ring 2 to rotate relative to the trimming disc 5 around the axis of the retaining ring 2, so as to grind and trim the ground surface of the retaining ring 2, and is also used to connect the wafer, so that the wafer is located in the area surrounded by the retaining ring 2, and to drive the wafer to perform chemical mechanical polishing.

[0073] In a specific embodiment, the specific structure of the chemical mechanical polishing unit and the specific process in which the polishing head 1 drives the retaining ring 2 to move so that the ground surface of the retaining ring 2 is ground and trimmed have been described above, and the specific process in which the polishing head 1 drives the wafer to perform chemical mechanical polishing is also described below, which will not be described herein again.

[0074] It should be noted that the chemical mechanical polishing unit of the embodiment is used in cooperation with the retaining ring trimming device in the foregoing embodiments and has the beneficial effects of the foregoing embodiments, which will not be described herein.

[0075] The embodiment of the present application further provides a chemical mechanical polishing unit control method for controlling the chemical mechanical polishing unit, Figure 13 is a flowchart of the chemical mechanical polishing unit control method of the embodiment of the present application. As shown in the figure, the chemical mechanical polishing unit control method comprises the following steps: Figure 13

[0076] Step 1301, when the chemical mechanical polishing unit is not connected with a wafer, controlling the polishing head 1 of the chemical mechanical polishing unit to drive the retaining ring 2 to abut against the side of the trimming disc 5 away from the base 4, so that the ground surface of the retaining ring 2 is away from the polishing head 1.

[0077] Step 1302, controlling the polishing head 1 to drive the retaining ring 2 to rotate relative to the trimming disc 5 around the axis of the retaining ring 2, so as to grind and trim the ground surface of the retaining ring 2.

[0078] In one specific embodiment, the chemical mechanical polishing unit control method can be applied to the controller or other controllers connected with the controller, and the embodiment of the present application does not limit this. The specific process of grinding and trimming the ground surface of the retaining ring 2 by the chemical mechanical polishing unit control method has been described above, and will not be described herein.

[0079] It should be noted that the chemical mechanical polishing unit control method of the embodiment is used for controlling the chemical mechanical polishing unit in the foregoing embodiments and has the beneficial effects of the foregoing embodiments, which will not be described herein.

[0080] The embodiment of the present application further provides a chemical mechanical polishing device, which comprises a polishing disc, a liquid supply member and the chemical mechanical polishing unit. The polishing disc is provided with a polishing pad on one side. The liquid supply member is used for providing polishing liquid to the side of the polishing pad away from the polishing disc. The polishing head 1 is further used for connecting a wafer, so that the wafer is located in the area surrounded by the retaining ring 2, and the ground polishing layer of the wafer abuts against the polishing pad. The polishing head 1 drives the wafer to move relative to the polishing pad, so as to perform chemical mechanical polishing on the wafer.

[0081] ​In one embodiment, the polishing pad is in the shape of a circular pad, the polishing disc is used to drive the polishing pad to rotate around the axis of the polishing pad, the liquid supply member can be a spray rod or the like, the liquid supply member can be connected with the polishing disc, and used to supply the polishing liquid to the side of the polishing pad away from the polishing disc (hereinafter referred to as the polishing surface), the polishing head 1 can adsorb the wafer through the air film 3, so that the wafer is located in the area surrounded by the retaining ring 2, in the chemical mechanical polishing process, the liquid supply member can supply the polishing liquid to the polishing surface, and the polishing head 1 can adsorb the wafer through the air film 3 and drive the wafer to move, so that the polished layer of the wafer (i.e. the layer of the wafer away from the air film 3 at this time) abuts against the side of the polishing pad away from the polishing disc, and then the polishing head 1 drives the wafer to rotate around the axis of the wafer relative to the polishing pad, and also drives the wafer to reciprocate on the polishing surface along the radial direction of the polishing surface, so as to polish the wafer. It should be noted that the chemical mechanical polishing device of the embodiment includes the chemical mechanical polishing unit of the foregoing embodiments, and has the beneficial effects of the corresponding foregoing embodiments, which will not be described here.

[0082] It should be noted that, in this document, the terms such as first and second are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0083] Finally, it should be noted that: the above is only the preferred embodiment of the present application, which is only used to illustrate the technical scheme of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application are included in the protection scope of the present application.

Claims

1. A retaining ring finishing device characterized by, The device comprises: a trimming disc arranged on one side of the base and comprising a carrier disc and at least one trimming block, the carrier disc being connected to the base and having two opposite circular annular surfaces in the thickness direction, one of the circular annular surfaces of the carrier disc being in abutment with the base, the trimming block being connected to the circular annular surface of the carrier disc away from the base, and being used for grinding and trimming the ground surface of the retaining ring when the polishing head of the chemical mechanical polishing unit drives the retaining ring to abut against the side of the trimming block away from the carrier disc, and for grinding and trimming the ground surface of the retaining ring in the process of rotating the retaining ring around the axis of the retaining ring relative to the trimming block driven by the polishing head; a detection member arranged on the base close to the carrier disc and electrically connected to the controller, and being used for detecting the shape data of the ground surface of the retaining ring through the detection opening of the carrier disc penetrating the carrier disc in the thickness direction, and sending the shape data to the controller in the process of grinding and trimming the retaining ring by the trimming disc; the controller being used for receiving the shape data, and controlling the polishing head to stop driving the retaining ring to rotate relative to the trimming disc to end the grinding and trimming of the retaining ring by the trimming disc when it is determined that the shape data meets the target condition indicating that the shape of the ground surface of the retaining ring is normal.

2. The apparatus of claim 1, wherein, The device further comprises a cleaning assembly; the cleaning assembly being connected to the base, and being used for cleaning the impurities attached to the ground surface of the retaining ring, and / or cleaning the impurities attached to the side of the carrier disc away from the base and the side of the trimming block away from the base after the grinding and trimming of the retaining ring by the trimming disc is ended.

3. The apparatus of claim 2, wherein, The base is provided with a chamber on the side close to the trimming disc, the bottom surface of the chamber is perpendicular to the axis direction of the carrier disc, and the cleaning assembly comprises a connecting shaft and at least one cleaning brush; the connecting shaft being located in the chamber, being in sliding connection with the base in the axis direction parallel to the carrier disc, and being in rotational connection with the base around the axis direction of the carrier disc; the cleaning brush being in sliding connection with the connecting shaft in the direction close to the connecting shaft and close to the bottom surface of the chamber, or in the direction away from the connecting shaft and away from the bottom surface of the chamber; the controller being used for controlling the polishing head to drive the retaining ring to separate from the trimming block according to the received first control instruction, and controlling the connecting shaft to drive the cleaning brush to move relative to the base in the direction away from the bottom surface of the base, and controlling the cleaning brush to slide away from the connecting shaft and away from the bottom surface of the chamber, so that at least part of the brush head of the cleaning brush is located between the retaining ring and the trimming disc, and being further used for controlling the connecting shaft to drive the cleaning brush to rotate relative to the base and controlling the cleaning brush to reciprocally slide relative to the connecting shaft according to the received second control instruction after at least part of the brush head is located between the retaining ring and the trimming disc.

4. The apparatus of claim 3, wherein, The cleaning brush further comprises a brush rod. The brush rod is in a straight rod shape, a distance between a first end of the brush rod and a bottom surface of the cavity is less than a distance between a second end of the brush rod and the bottom surface of the cavity, the first end of the brush rod is slidably connected to the connecting shaft along a length direction of the brush rod, and the second end of the brush rod is connected to the brush head.

5. The device of any one of claims 3 or 4, wherein, The brush head comprises a first head and a second head. The first head and the second head are arranged in a direction perpendicular to the bottom surface of the base, the first head is farther away from the bottom surface of the base than the second head, at least part of the brush hairs of the first head abut against the ground surface of the retaining ring when at least part of the brush head is located between the retaining ring and the trimming disc, and at least part of the brush hairs of the second head abut against the side surface of the carrier disc away from the base and / or the side surface of the trimming block away from the base.

6. The apparatus of claim 2, wherein, The cleaning assembly further comprises a first nozzle. The first nozzle is arranged on a side of the base close to the trimming disc, and is used to spray liquid to the trimming disc when the cleaning assembly cleans the impurities attached to the side surface of the carrier disc away from the base and the side surface of the trimming block away from the base.

7. The apparatus of claim 3, wherein, The device further comprises a circular wafer receiving ring. An axis of the wafer receiving ring is perpendicular to the bottom surface of the cavity, the wafer receiving ring is connected to the connecting shaft, the wafer receiving ring is used to receive a wafer, and an avoiding opening is arranged on the wafer receiving ring to avoid the sliding path of the cleaning brush relative to the connecting shaft.

8. The apparatus of claim 1, wherein, The base is connected with a driving member. The driving member is used to drive the base to move in a direction perpendicular to the surface of the trimming disc.

9. The apparatus of claim 1, wherein, The same shape data detected by the same detection member comprises the distance between a plurality of position points on any ring width line of the ground surface of the retaining ring and the detection head of the detection member.

10. A chemical mechanical polishing unit, characterized by The chemical mechanical polishing unit is used in cooperation with the retaining ring trimming device, and comprises a retaining ring and a polishing head; The retaining ring is connected to one side of the polishing head; The polishing head is used to drive the retaining ring to abut against the side surface of the trimming disc away from the base with the ground surface of the retaining ring away from the polishing head, and is used to drive the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring to grind and trim the ground surface of the retaining ring, and is used to connect a wafer so that the wafer is located in an area surrounded by the retaining ring and drive the wafer to perform chemical mechanical polishing.

11. A chemical mechanical polishing unit control method, characterized by, The chemical mechanical polishing unit control method is used to control the chemical mechanical polishing unit, and the chemical mechanical polishing unit control method comprises: When the chemical mechanical polishing unit is not connected with a wafer, the polishing head of the chemical mechanical polishing unit is controlled to drive the retaining ring to abut against the side surface of the trimming disc away from the base with the ground surface of the retaining ring away from the polishing head; The polishing head is controlled to drive the retaining ring to rotate relative to the trimming disc around the axis of the retaining ring to grind and trim the ground surface of the retaining ring.

12. A chemical mechanical polishing apparatus characterized by comprising: The chemical mechanical polishing unit comprises a polishing disc, a liquid supply member and the chemical mechanical polishing unit. The polishing disc is provided with a polishing pad on one side. The liquid supply member is configured to supply the polishing liquid to the side of the polishing pad away from the polishing disk. The polishing head is further configured to connect the wafer so that the wafer is located in the area surrounded by the retaining ring and the polished layer of the wafer abuts against the polishing pad, and the wafer is driven to move relative to the polishing pad to perform chemical mechanical polishing on the wafer.

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