Grinding head cleaning assembly and polishing machine table

Abstract

The embodiment of the utility model discloses a grinding head cleaning assembly and a polishing machine table, the grinding head cleaning assembly is configured to be aligned with a grinding head in the first direction and clean the grinding head, and the grinding head is provided with a membrane and a retaining ring which is located on the edge of the membrane and surrounds the membrane; a gap is formed between the diaphragm and the retaining ring, and the grinding head cleaning assembly comprises a first spray head corresponding to the retaining ring; the second spray head corresponds to the gap, and the third spray head corresponds to the diaphragm; and the second spray head is configured to spray the columnar cleaning liquid and adjust the spraying angle.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to the field of semiconductor technology, and in particular, to a polishing head cleaning assembly and a polishing machine. Background Art

[0002] Chemical Mechanical Polishing (CMP) is one of the key processes for achieving wafer surface planarization in the integrated circuit manufacturing process. Different from some pure mechanical polishing and grinding processes, the CMP process combines surface chemical action and mechanical grinding technology to remove the thickness of micron / nano-scale materials on the wafer surface, so as to achieve less thickness removal on the wafer surface and a higher surface flatness morphology performance.

[0003] The main working principle of the CMP process is that under a certain pressure and in the presence of a slurry, the wafer to be polished makes a relative movement with respect to the polishing pad. With the highly organic combination between the mechanical grinding action of nano-abrasives and the chemical action of various chemical reagents, the surface of the wafer to be polished reaches a high degree of planarization, meeting the process requirements of low surface roughness and low defects. When performing the CMP process, the wafer is adsorbed by the polishing head, and the polishing head also applies a vertically downward pressure to the wafer to make the wafer close to the surface of the polishing pad and drive the wafer to rotate so that the wafer and the polishing pad rub against each other under the wetting of the polishing liquid, thereby polishing the surface of the wafer. After the wafer undergoes the CMP process, the polishing head will remain with slurry and residue of polishing by-products, and it is necessary to clean the polishing head to remove them to reduce scratches and chips on the subsequent wafers. The CMP machine has a cleaning assembly for cleaning the polishing head, and there is still some room for improvement in the cleaning performance of the polishing head cleaning assembly. Summary of the Utility Model

[0004] According to some aspects of the embodiments of the present disclosure, a polishing head cleaning assembly is provided. The polishing head cleaning assembly is configured to align with the polishing head along a first direction and clean the polishing head. The polishing head is provided with a diaphragm and a retaining ring located at the edge of the diaphragm and surrounding the diaphragm. There is a gap between the diaphragm and the retaining ring. The polishing head cleaning assembly includes: a first spray head corresponding to the retaining ring; a second spray head corresponding to the gap; a third spray head corresponding to the diaphragm; wherein, the second spray head is configured to: spray columnar cleaning liquid and adjust the spraying angle.

[0005] In some embodiments, the polishing head cleaning assembly further includes:

[0006] a first pipeline communicating with the first spray head and the third spray head;

[0007] A second pipeline, which is communicated with the second nozzle; the hydraulic pressure for supplying liquid of the second pipeline is greater than or equal to the hydraulic pressure for supplying liquid of the first pipeline.

[0008] In some embodiments, the third nozzle is configured to eject a water curtain, and the cross-sectional shape of the water curtain along the first direction includes:

[0009] A first included angle; the vertex of the first included angle is located at the liquid ejection port of the third nozzle, and two sides of the first included angle are provided by the edges of the water curtain.

[0010] In some embodiments, the grinding head cleaning assembly further includes:

[0011] A carrier plate, on which the first nozzle, the second nozzle and the third nozzle are embedded; the liquid ejection ports of the first nozzle, the second nozzle and the third nozzle are exposed on the surface of the carrier plate close to the grinding head.

[0012] In some embodiments, the liquid ejection port of the first nozzle protrudes from the carrier plate by a first height, the second nozzle protrudes from the carrier plate by a second height, and the third nozzle protrudes from the carrier plate by a third height; wherein, the second height is greater than the first height; and / or, the second height is greater than the third height.

[0013] In some embodiments, the grinding head cleaning assembly further includes:

[0014] A rotating shaft, which is located below the carrier plate, and the rotating shaft drives the carrier plate to rotate in the opposite direction relative to the grinding head.

[0015] In some embodiments, the grinding head cleaning assembly further includes:

[0016] A cavity, in which the carrier plate is located; an opening is provided on one side of the cavity close to the grinding head, and the carrier plate is exposed from the opening.

[0017] In some embodiments, the first nozzle has a first distance from the center of the carrier plate, the second nozzle has a second distance from the center of the carrier plate, and the third nozzle has a third distance from the center of the carrier plate;

[0018] The first distance is greater than the second distance, and the second distance is greater than the third distance.

[0019] In some embodiments, the grinding head cleaning assembly further includes:

[0020] A cleaning brush, and a connecting arm connecting the cleaning brush;

[0021] The connecting arm is configured to:

[0022] Drive the cleaning brush close to the grinding head and press it against the gap.

[0023] According to some aspects of the embodiments of the present disclosure, a polishing machine platform is provided, including:

[0024] The grinding head cleaning assembly according to any one of the above; the polishing machine platform further includes:

[0025] A grinding table for carrying a polishing pad;

[0026] A grinding head; the grinding head is used to adsorb a wafer and apply pressure to the wafer to make the wafer close to the polishing pad, and the grinding head drives the wafer to rotate on the polishing pad;

[0027] A dressing assembly, including a dressing arm and a dressing head; the dressing arm drives the dressing head to press against the polishing pad and swing horizontally on the polishing pad, and the dressing head rotates;

[0028] A liquid supply assembly for providing abrasive liquid to the surface of the polishing pad.

[0029] The embodiments of the present disclosure provide a grinding head cleaning assembly. The grinding head cleaning assembly can be aligned with the grinding head in the first direction (vertical direction). The nozzle of the grinding head cleaning assembly sprays cleaning liquid towards the grinding head to clean the grinding head; the grinding head is provided with a diaphragm and a retaining ring located at the edge of the diaphragm and surrounding the diaphragm. The retaining ring is used to limit the position of the wafer to prevent the wafer from shifting, and the diaphragm is used to adsorb and apply pressure to the wafer. There is a gap between the diaphragm and the retaining ring; the first nozzle of the grinding head cleaning assembly corresponds to the retaining ring, the second nozzle corresponds to the gap, and the third nozzle corresponds to the diaphragm; the second nozzle can be adjusted to be configured to spray high-pressure columnar cleaning liquid and adjust the spraying angle to efficiently clean the abrasive liquid crystals, grinding by-products, etc. in the gap, reduce the risk of wafer scratches and fragments, and improve the CMP yield. Description of the Drawings

[0030] Figure 1 is a schematic diagram of an exemplary polishing machine platform shown according to the embodiments of the present disclosure;

[0031] Figure 2 is a schematic diagram of an exemplary grinding head shown according to the embodiments of the present disclosure;

[0032] Figures 3 to 9 is a schematic diagram of an exemplary grinding head cleaning assembly shown according to the embodiments of the present disclosure.

[0033] In the above drawings (which are not necessarily drawn to scale), like reference numerals may describe like components in different views. Like reference numerals with different letter suffixes may represent different examples of like components. The drawings generally illustrate, by way of example and not limitation, the various embodiments discussed herein. Detailed Description

[0034] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited by the specific embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0035] In the following description, numerous specific details are given to provide a more thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without one or more of these details. In other instances, well-known features have not been described in order to avoid obscuring the present disclosure; that is, not all features of actual embodiments are described here, and well-known functions and structures are not described in detail.

[0036] It should be understood that when an element or layer is referred to as being "on", "adjacent to", "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on", "directly adjacent to", "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or portions, these elements, components, regions, layers and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or portion from another element, component, region, layer or portion. Thus, a first element, component, region, layer or portion discussed below may be referred to as a second element, component, region, layer or portion without departing from the teachings of the present disclosure. And when discussing a second element, component, region, layer or portion, it does not imply that a first element, component, region, layer or portion necessarily exists in the present disclosure.

[0037] Spatial relationship terms such as "under", "below", "beneath", "underneath", "above", "over", etc. may be used herein for convenience of description to describe the relationship of one element or feature shown in the figure with other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relationship terms are also intended to include different orientations of the device during use and operation. For example, if the device in the attached drawing is flipped, then an element or feature described as "under other elements" or "beneath it" or "under it" will be oriented "above" the other elements or features. Thus, the exemplary terms "under" and "beneath" can include both the upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are to be interpreted accordingly.

[0038] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present disclosure. As used herein, the singular forms "a", "an", and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. As used herein, the term "and / or" includes any and all combinations of the related listed items.

[0039] It should be understood that "some embodiments" or "an embodiment" mentioned throughout the specification means that a particular feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of "in some embodiments" or "in an embodiment" throughout the specification are not necessarily referring to the same embodiment. In addition, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that in various embodiments of the present disclosure, the magnitudes of the sequence numbers of the above processes do not imply the order of execution, and the order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present disclosure.

[0040] According to some aspects of the embodiments of the present disclosure, Figure 1 An exemplary polishing machine table 100 is provided. The polishing machine table 100 may be a CMP machine table. The polishing machine table 100 may include:

[0041] A polishing table 101 for carrying a polishing pad 102;

[0042] A polishing head 103; the polishing head 103 is used to adsorb a wafer and apply pressure to the wafer to make the wafer close to the polishing pad 102, and the polishing head 103 drives the wafer to rotate on the polishing pad 102; asFigure 2 As shown, on one side of the grinding head 103 for adsorbing the wafer, there is provided, or includes, a diaphragm 1031 and a retaining ring 1032 located at the edge of the diaphragm 1031 and surrounding the diaphragm 1031. There is a gap 1033 between the diaphragm 1031 and the retaining ring 1032;

[0043] The grinding head cleaning assembly 110 is located on one side in the horizontal direction of the grinding table 101, such as on one side in the x direction of the grinding table 101; the grinding head cleaning assembly 110 includes a plurality of spray heads 111, and the plurality of spray heads 111 can be communicated with a liquid supply pipeline;

[0044] The dressing assembly 104 includes a dressing arm and a dressing head; the dressing arm drives the dressing head to closely adhere to the polishing pad 102 and swing in the horizontal direction on the polishing pad 102, and the dressing head rotates;

[0045] The liquid supply assembly 105 is used to supply abrasive liquid to the surface of the polishing pad 102.

[0046] In some embodiments, referring to Figure 1As shown, the polishing table 101 can be set on the carrier, and the polishing pad 102 is fixed on the surface of the polishing table 101. The fixing method can include adsorption and adhesive pasting. The polishing pad 102 is a replaceable consumable. The polishing head 103 can be set above the polishing table 101. The polishing head 103 can have a flexible chamber to adsorb and fix the wafer. For example, the flexible buffer diaphragm 1031 of the polishing head 103 and the retaining ring 1032 around the edge of the diaphragm 1031. The retaining ring 1032 can include ceramics or flexible rubber, and the diaphragm 1031 can include flexible materials such as rubber, polyurethane, and gel that can generate elastic deformation under external force. The retaining ring 1032 can protrude towards the polishing table 101. The retaining ring 1032 and the diaphragm 1031 enclose a chamber to fix and accommodate the wafer. The polishing head 103 aligns with the wafer carrier on the horizontal side of the polishing table 101 and moves downward to contact the wafer placed on the wafer carrier. The wafer is sleeved into the retaining ring 1032, and the internal air is extruded through the deformation of the diaphragm 1031 to generate a vacuum adsorption force or a holding force to fix the wafer. The polishing head 103 adsorbs the wafer and moves horizontally above the polishing table 101. It moves downward along the z direction to make the wafer contact the polishing pad 102. The polishing head 103 applies a downward pressure to the wafer to make the wafer closely adhere to the polishing pad 102. The polishing head 103 makes a horizontal rotational movement to drive the wafer to polish on the polishing pad 102. The retaining ring 1032 can protrude from the wafer to prevent the wafer from shifting when the wafer contacts the polishing pad 102 for polishing. The retaining ring 1032 also contacts the polishing pad 102. The retaining ring 1032 is more wear-resistant than the wafer. The retaining ring 1032 has a lower polishing rate or is basically not worn on the surface of the polishing pad 102. The retaining ring 1032 and the diaphragm 1031 are replaceable consumable parts. The end of the retaining ring 1032 that protrudes from the wafer and points to the polishing pad 102 can have a groove 1034 for the conduction of the polishing liquid to reduce the splashing of the polishing liquid. Adapted to the shape of the wafer, the polishing head 103, the diaphragm 1031, and the retaining ring 1032 can be circular shapes adapted to the shape and size of the wafer.

[0047] The polishing table 101 can be stationary or make a relative rotational movement in the opposite direction to the rotational direction of the polishing head 103. The dressing assembly 104 can include a dressing arm and a dressing head, and can be set on one side of the polishing table 101. The dressing arm can drive the rotating dressing head to swing to dress and clean the surface of the polishing pad 102 to make the polishing pad 102 smooth and wrinkle-free, and can also sweep away the polishing liquid and polishing by-products on the polishing pad 102. The liquid supply assembly 105 supplies the polishing liquid to the surface of the polishing pad 102. The polishing liquid can include components such as alumina, silica, polyurethane, water, and surfactant, or various small-sized microspheres formed by the above alumina, silica, polyurethane and other materials. The liquid supply assembly 105 can be connected to the liquid storage tank or the liquid mixing system of the machine tool through a pipeline to obtain the polishing liquid and supply it to the surface of the polishing pad 102.

[0048] During the CMP process, the chemical components in the polishing slurry can chemically react with the material to be removed on the wafer surface, softening these materials or converting them into soluble substances. This step helps to reduce the hardness of the material surface, making it easier to remove mechanically. Through the relative movement between the polishing pad 102 and the wafer, and the applied pressure, the abrasive in the polishing slurry and the polishing pad 102 physically remove the wafer surface. This mechanical action effectively removes the softened material, thus achieving the planarization of the material surface. The combined use of chemical action and mechanical action can avoid the processing damage caused by relying solely on mechanical polishing, as well as the problems of low polishing efficiency and poor surface flatness caused by using chemical polishing alone.

[0049] In some embodiments, the surface of the polishing pad 102 may have strip-shaped or annular grooves. The grooves can increase the roughness of the surface of the polishing pad 102, make the polishing slurry more evenly distributed on the surface of the polishing pad 102, and also discharge the by-products ground from the wafer. As the polishing time increases, the polishing pad 102 will be consumed, and the depth of the grooves on the surface of the polishing pad 102 will decrease. When the polishing time of the polishing pad 102 or the number of wafers ground reaches a certain set value, the polishing pad 102 needs to be replaced.

[0050] In some embodiments, referring to Figure 2 As shown, a diaphragm 1031 and a retaining ring 1032 located at the edge of the diaphragm 1031 and surrounding the diaphragm 1031 are provided on the side of the polishing head 103 that adsorbs the wafer. Channels or chambers for gas flow can be provided on the back of the diaphragm 1031 that does not contact the wafer, or on the side away from the wafer. Air can be pumped out on the back of the diaphragm 1031 that does not contact the wafer to deform the diaphragm 1031 to adsorb the wafer; after the wafer contacts the polishing pad 102, air can be introduced on the back of the diaphragm 1031 to press the diaphragm 1031 against the wafer, making the wafer closely adhere to the polishing pad 102 and increasing the friction to improve the polishing efficiency. In some other embodiments, the polishing head 103 can be provided with a gas guiding channel or a gas guiding groove on the back of the diaphragm 1031. The diaphragm 1031 can be provided with air holes connected to the gas guiding channel. When the gas guiding channel pumps air, the wafer is adsorbed; when the gas guiding channel jets air, the wafer is pressed or the adsorption of the wafer is released; or the gas guiding channel communicates with the gap 1033 between the diaphragm 1031 and the retaining ring 1032 to achieve the vacuum adsorption of the wafer.

[0051] In some embodiments, the polishing head 103 will adhere to polishing liquid and polishing by-products. Before the polishing head 103 desorbs or adsorbs the wafer, the polishing head 103 can be cleaned. Specifically, the diaphragm 1031 and the retaining ring 1032 of the polishing head 103 can be cleaned. The polishing head 103 without adsorbed wafer moves horizontally (in the x or y direction) and vertically (in the z direction) above the polishing head cleaning assembly 110 and aligns with the polishing head cleaning assembly 110. The nozzle 111 of the polishing head cleaning assembly 110 sprays cleaning liquid towards the polishing head 103 to clean the polishing head 103. Refer to Figure 3 As shown in the example, the polishing head 103 moves above the polishing head cleaning assembly 110 and aligns with the polishing head cleaning assembly 110. The nozzle 111 of the polishing head cleaning assembly 110 sprays cleaning liquid to clean the polishing head 103.

[0052] In some embodiments, Figure 4 Fig. shows a schematic diagram of the polishing head cleaning assembly 110 and the polishing head 103 being aligned in the z direction for cleaning. There is a gap 1033 between the retaining ring 1032 and the diaphragm 1031 of the polishing head 103. This gap 1033 can be a contact seam formed when the two components are installed and in contact. The polishing head 103 can have multiple nozzles 111. The nozzles 111 can clean the edge of the diaphragm 1031, the retaining ring 1032, and the central area of the diaphragm 1031. The cleaning liquid sprayed by the nozzles 111 can be a water curtain, a liquid curtain, or a water column. For example, it can be a 30° umbrella-shaped water curtain with a certain coverage range to cover and clean a larger area of the polishing head 103 region. The cleaning liquid can include but is not limited to: deionized water, ultrapure water, or a weak acid or weak alkaline cleaning liquid including a surfactant. Figure 4 As shown, there may be some difficult-to-clean polishing liquid crystals and polishing by-product crystals in the gap 1033 between the diaphragm 1031 and the retaining ring 1032. The nozzle 111 is not aligned with the gap 1033, and the umbrella-shaped water curtain sprayed by the nozzle is difficult to concentrate the water pressure to focus on cleaning the gap 1033, resulting in a poor cleaning effect. In view of this, an embodiment of the present disclosure provides a polishing head cleaning assembly 110. At least one nozzle 111 of the polishing head cleaning assembly 110 can correspond to the gap 1033 between the diaphragm 1031 and the retaining ring 1032. This nozzle 111 can be aligned with the gap 1033 in the z direction, spray a high-pressure water column to focus on cleaning the gap 1033, and this nozzle 111 can adjust the spraying angle to better align with the gap 1033.

[0053] According to some aspects of the embodiments of the present disclosure, Figure 5Provided is a cleaning assembly for a polishing head 103. The polishing head cleaning assembly 110 is configured to be aligned with the polishing head 103 in a first direction (z-direction) and clean the polishing head 103. The polishing head 103 is provided with a diaphragm 1031 and a retaining ring 1032 located at the edge of the diaphragm 1031 and surrounding the diaphragm 1031. There is a gap 1033 between the diaphragm 1031 and the retaining ring 1032. The polishing head cleaning assembly 110 includes:

[0054] A first spray head 1111, corresponding to the retaining ring 1032;

[0055] A second spray head 1112, corresponding to the gap 1033;

[0056] A third spray head 1113, corresponding to the diaphragm 1031;

[0057] Wherein, the second spray head 1112 is configured to: spray a columnar cleaning liquid and adjust the spraying angle. The first direction can be the z-direction in the figure, can be the vertical direction, and can be the wafer thickness direction.

[0058] Referring to Figure 5 As shown, a cleaning schematic diagram of the polishing head 103 and the polishing head cleaning assembly 110 when they are aligned in the z-direction or within a certain error range is shown. The first spray head 1111 is aligned with the retaining ring 1032 in the z-direction, or is substantially aligned with the retaining ring 1032 within a certain error range. The second spray head 1112 is aligned with the gap 1033 in the z-direction, and the third spray head 1113 is aligned with the diaphragm 1031. Specifically, a plurality of third spray heads 1113 can be arranged to sequentially align with the edge region and the middle region of the diaphragm 1031 from the outside to the inside. The second spray head 1112 sprays a high-pressure, columnar cleaning liquid, and sprays it concentratedly towards the gap 1033 with a relatively large pressure to wash the residues on the gap 1033. During the cleaning process, the polishing head 103 can rotate so that each region of the polishing head 103 can be cleaned by the cleaning liquid.

[0059] Referring to Figure 6 As exemplified by the second spray head 1112, the spraying angle can be adjusted, for example, tilted along the z-direction or other directions, forming an angle with the z-direction, such as -90° to 90°, to change the spraying angle of the second spray head 1112 so that the sprayed cleaning liquid is aligned with the gap 1033. Exemplarily, the second spray head 1112 can include a spray head that adjusts the spraying angle electrically or pneumatically, or can be a spray head that manually adjusts the angle of the spray head 111; the first spray head 1111 and the third spray head 1113 can also include spray heads with adjustable spraying angles.

[0060] The first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 can be arranged on the concentrically arranged liquid supply pipeline. All the nozzles can be supplied with liquid uniformly, and the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 can be independently supplied with liquid respectively to provide different water pressures. For the arrangement of the first nozzles 1111, multiple first nozzles 1111 can be arranged in a circular pattern, and multiple first nozzles 1111 are connected to the first pipeline for liquid supply; multiple second nozzles 1112 are arranged in a circular pattern, and multiple second nozzles 1112 are connected to the second pipeline for liquid supply; multiple third nozzles 1113 are arranged in a circular pattern and connected to the third pipeline or connected to the first pipeline. Because the diaphragm 1031 has a large area, multiple circles of third nozzles 1113 can be arranged, or arranged in multiple areas, so that the cleaning liquid evenly covers the diaphragm 1031. The second pipeline is a high-pressure liquid supply pipeline, for example, the water pressure is 30 - 35 psi, and the first pipeline and / or the third pipeline is a low-pressure liquid supply pipeline, for example, the water pressure is 0 - 30 psi. In some embodiments, the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 can be embedded in the carrier plate 1101, the liquid spraying ports of the nozzles 111 face the grinding head 103 and expose from the carrier plate 1101. The nozzles 111 can protrude from the carrier plate 1101 or not protrude from the carrier plate 1101, and a part of the liquid supply pipeline of the nozzles 111 is arranged in the carrier plate 1101.

[0061] In some embodiments, with reference to Figure 7 as shown, the grinding head cleaning assembly 110 further includes:

[0062] A carrier plate 1101, on which the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 are embedded; the liquid spraying ports of the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 are exposed on the surface of the carrier plate 1101 close to the grinding head 103. The embodiments of the present disclosure do not limit the number of the first nozzles 1111, the second nozzles 1112, and the third nozzles 1113.

[0063] With reference to Figure 7As an example, three first nozzles 1111 can be embedded in the edge area of the carrier plate 1101. The three first nozzles 1111 can be aligned with the snap ring 1032 in the z direction. The three first nozzles 1111 can be arranged in concentric circles relative to the carrier plate 1101, that is, the distances from the three nozzles 1111 to the center of the carrier plate 1101 are equal. The connecting lines between the three first nozzles 1111 and the center of the carrier plate 1101 can divide the carrier plate 1101 evenly, and the central angle between adjacent connecting lines is 120°. Three second nozzles 1112 can be set to be aligned with the gap 1033 between the diaphragm 1031 and the snap ring 1032 in the z direction. The width of the gap 1033 can be 1-1.5 mm. The second nozzles 1112 are closer to the center of the carrier plate 1101 by 1-3 mm, such as 2 mm, in the diameter direction of the carrier plate 1101 relative to the first nozzles 1111. Alternatively, the distance from the first nozzles 1111 to the center of the carrier plate 1101 is greater than the distance from the second nozzles 1112 to the center of the carrier plate 1101, and the distance difference can be 2 mm. The third nozzles 1113 are closer to the center of the carrier plate 1101 in the diameter direction of the carrier plate 1101 relative to the second nozzles 1112. The distance from the second nozzles 1112 to the center of the carrier plate 1101 is greater than the distance from the third nozzles 1113 to the center of the carrier plate 1101. The diaphragm 1031 has a large area, and multiple third nozzles 1113 can be arranged in sub-regions. It can be divided into three regions, and three third nozzles 1113 are distributed in one region and arranged in a triangle so that the cleaning liquid sprayed by the multiple third nozzles 1113 is evenly distributed on the diaphragm 1031. In some other embodiments, since the grinding head 103 can rotate during the cleaning process, the cleaning liquid can cover the diaphragm 1031 and the snap ring 1032, and there is no strict limit on the distribution of the nozzles 111. The first nozzles 1111, the second nozzles 1112, and the third nozzles 1113 can have other distribution schemes.

[0064] In some embodiments, the grinding head cleaning assembly 110 further includes:

[0065] A first pipeline, communicating with the first nozzles 1111 and the third nozzles 1113; a second pipeline, communicating with the second nozzles 1112.

[0066] In some embodiments, the liquid supply pressure of the second pipeline is greater than or equal to that of the first pipeline. The residue in the slit 1033 is difficult to clean. The injection pressure of the second nozzle 1112 for cleaning the residue in the slit 1033 can be increased, and the liquid supply pressure of the liquid supply pipeline of the second nozzle 1112 can be increased. When multiple second nozzles 1112 are provided, for example, 3 second nozzles 1112 are provided, the 3 second nozzles 1112 can be arranged in concentric circles. The connecting lines between the 3 first nozzles 1111 and the center of the carrier plate 1101 can evenly divide the carrier plate 1101, and the central angle between adjacent connecting lines is 120°. To facilitate liquid supply to the multiple second nozzles 1112 and reduce the pressure drop caused by the blockage of the pipeline wall, an annular second pipeline can be provided to communicate with the 3 first nozzles 1111. The liquid supply pressure of the second pipeline is relatively high, such as 30-35 psi. The first nozzle 1111 and the third nozzle 1113 can be adapted to the same liquid supply pressure, such as the second pipeline. The second pipeline can include multiple sub-pipelines. For example, the first sub-pipeline communicates with the 3 first nozzles 1111, and the second sub-pipeline or more sub-pipelines communicate with the 9 third nozzles 1113. Each sub-pipeline of the second pipeline can include a strip-shaped pipeline and / or an annular pipeline sleeved in concentric circles. The pipeline can be a stainless steel pipeline, a polypropylene pipeline, or a stainless steel pipeline with a polytetrafluoroethylene lining. The first pipeline and the second pipeline can communicate with the main pipeline of the machine tool. The main pipeline is connected to the factory liquid supply pipeline or the secondary distribution liquid supply device of the machine tool. Valves can be provided between the first pipeline and the second pipeline and the upstream liquid supply pipeline to control the liquid supply and cut-off of the pipeline. The valve can be configured to be controlled by the control unit of the machine tool to open and close. A part of the first pipeline and a part of the second pipeline can be embedded in the carrier plate 1101, and a part of the first pipeline and a part of the second pipeline can be located below the carrier plate 1101 and communicate with the secondary distribution liquid supply device of the machine tool.

[0067] In some embodiments, the third nozzle 1113 is configured to spray a water curtain, and the cross-sectional shape of the water curtain along the first direction includes:

[0068] A first included angle; the vertex of the first included angle is located at the liquid spraying port of the third nozzle 1113, and the two sides of the first included angle are provided by the edges of the water curtain.

[0069] The first nozzle 1111 and the third nozzle 1113 can spray a water curtain with a larger coverage range than the water column of the second nozzle 1112. For example, it can be a 30° umbrella-shaped water curtain with a certain coverage range. Taking the third nozzle 1113 as an example, the cross-sectional shape of the water curtain along the z direction is a triangle, a cone, or an umbrella shape that expands from the liquid spraying port to both sides, with a first included angle that expands from the third nozzle 1113 as the vertex to both sides, such as 30°, 45°, etc., so that the cleaning liquid can cover a larger area of the diaphragm 1031 after reaching the diaphragm 1031 to achieve a larger area of cleaning. For example, Figure 5The water curtain with a triangular cross-section sprayed by the first nozzle 1111 and the second nozzle 1112 of the illustrated example towards the grinding head 103.

[0070] In some embodiments, referring to Figure 8 As shown, the liquid spraying orifice of the first nozzle 1111 protrudes from the bearing plate 1101 by a first height, the second nozzle 1112 protrudes from the bearing plate 1101 by a second height, and the third nozzle 1113 protrudes from the bearing plate 1101 by a third height; wherein, the second height is greater than the first height; and / or, the second height is greater than the third height. Taking the bearing plate 1101 as a reference surface, the second nozzle 1112 can protrude more from the bearing plate 1101 relative to the first nozzle 1111, and the second nozzle 1112 can protrude more from the bearing plate 1101 relative to the third nozzle 1113; the second nozzle 1112 can be closer to the gap 1033, and the columnar cleaning liquid sprayed by the second nozzle 1112 is more concentrated on the gap 1033, improving the cleaning ability of the gap 1033.

[0071] In some embodiments, referring to Figure 9 As shown, the grinding head cleaning assembly 110 further includes:

[0072] A rotating shaft 1102, located below the bearing plate 1101, and the rotating shaft 1102 drives the bearing plate 1101 to rotate in the opposite direction relative to the grinding head 103. The rotating shaft 1102 extends along the z direction. One end of the rotating shaft 1102 in the z direction can be fixedly connected or gear-connected to the bearing plate 1101, and the other end of the rotating shaft 1102 is power-connected to a motor. The motor drives the rotating shaft 1102 to rotate, the rotating shaft 1102 drives the bearing plate 1101 to rotate, and the rotating direction of the bearing plate 1101 is opposite to that of the grinding head 103. For example, the grinding head 103 can rotate in the counterclockwise direction, and the rotating shaft 1102 drives the bearing plate 1101 to rotate in the clockwise direction, providing a reaction force of the cleaning liquid relative to the grinding head 103 to impact the residues on the grinding head 103, further improving the cleaning efficiency.

[0073] In some embodiments, referring to Figure 9 As shown, the grinding head cleaning assembly 110 further includes:

[0074] A cavity 1103, and the bearing plate 1101 is located in the cavity 1103; one side of the cavity 1103 close to the grinding head 103 has an opening, and the bearing plate 1101 is exposed from the opening. The cavity 1103 has an opening towards the positive z direction, the bearing plate 1101 is located in the cavity 1103, and the side wall of the cavity 1103 surrounds the bearing plate 1101 to provide protection for the bearing plate 1101 and prevent the cleaning liquid from splashing. A drain port can be provided at the bottom of the cavity 1103, which is communicated with the waste liquid collection device of the machine table, and the drain port is used to drain the cleaning liquid. The side of the bearing plate 1101 where the nozzles are arranged is exposed from the opening of the cavity 1103 and faces the grinding head 103 after being aligned with the grinding head 103.

[0075] In some embodiments, with reference to Figure 8 As shown, for the convenience of explanation, the center O of the carrier plate 1101 can be marked. In fact, such a center mark may not exist on the physical surface of the carrier plate 1101. The first nozzle 1111 has a first distance D1 from the center O of the carrier plate 1101, the second nozzle 1112 has a second distance D2 from the center O of the carrier plate 1101, and the third nozzle 1113 has a third distance D3 from the center O of the carrier plate 1101; the first distance D1 is greater than the second distance D2, and the second distance D2 is greater than the third distance D3. Taking the first nozzle 1111 as an example, the first distance D1 can be the straight-line distance between the center of the first nozzle 1111 and the center O, or the distance between a certain horizontal side of the first nozzle 1111 and the center O.

[0076] Along the diameter direction of the carrier plate 1101, the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 are sequentially arranged from the edge to the center of the carrier plate 1101. Exemplarily, the distance difference between the first distance D1 and the second distance D2 can be 1-3 mm, such as 2 mm. Corresponding to the larger flushing area of the diaphragm 1031, a plurality of third nozzles 1113 arranged along the x direction can be provided. The third distance D3 between the outermost third nozzle 1113 of the carrier plate 1101 and the center of the carrier plate 1101 is less than the second distance D2.

[0077] In some embodiments, with reference to Figure 9 As shown, the polishing head cleaning assembly 110 further includes:

[0078] A cleaning brush 121 and a connecting arm 122 connecting the cleaning brush 121;

[0079] The connecting arm 122 is configured to:

[0080] Drive the cleaning brush 121 to approach the polishing head 103 and closely adhere to the gap 1033.

[0081] The cleaning brush 121 may include a flexible material, and the shape of the cleaning brush 121 can be circular, oval, rectangular or arc-shaped. The arc-shaped cleaning brush 121 can be adapted to the shape of the arc-shaped gap 1033 and can be embedded in the gap 1033 to improve the brushing level. The connecting arm 122 can be arranged on the left side of the carrier plate 1101. The connecting arm 122 can move up and down along the z direction or can rotate to drive the cleaning brush 121 to approach the gap 1033 of the polishing head 103. The connecting arm 122 is arranged on a fixed shaft or a fixed seat of the polishing head 103 cleaning device. The connecting shaft can be folded and disassembled, and the cleaning brush 121 can be detachably replaced.

[0082] Exemplarily, before the polishing head 103 is aligned with the polishing head cleaning assembly 110, the connecting arm 122 rotates counterclockwise from left to right or from the outside of the carrier plate 1101 towards the center of the carrier plate 1101, driving the cleaning brush 121 to move above the carrier plate 1101 and stop at the target position; the polishing head 103 moves above the polishing head cleaning assembly 110 to complete alignment, the polishing head 103 moves downward to the target position so that the gap 1033 contacts the cleaning brush 121, and the connecting arm 122 moves up and down to adjust the position or not to ensure good contact between the cleaning brush 121 and the gap 1033 of the polishing head 103; the first nozzle 1111, the second nozzle 1112, and the third nozzle 1113 spray the cleaning liquid, the polishing head 103 rotates counterclockwise, and the carrier plate 1101 can rotate clockwise or not. After running for a certain cleaning time, the cleaning liquid stops spraying, the polishing head 103 lifts upward away from the polishing head cleaning device and moves to the wafer carrier stage, and the polishing head 103 grabs the wafer for the CMP process; the connecting arm 122 rotates clockwise to drive the cleaning brush 121 to move out of the surface of the carrier plate 1101.

[0083] According to some aspects of the embodiments of the present disclosure, Figure 1 a polishing machine platform 100 is provided, including: Figure 1 、 Figures 3 to 9 the polishing head cleaning assembly 110 shown in the figure; the polishing machine platform 100 further includes:

[0084] a polishing table 101 for carrying a polishing pad 102;

[0085] a polishing head 103; the polishing head 103 is used to adsorb the wafer and apply pressure to the wafer to make the wafer close to the polishing pad 102, and the polishing head 103 drives the wafer to rotate on the polishing pad 102; the polishing head 103 is provided with a diaphragm 1031 and a retaining ring 1032 located at the edge of the diaphragm 1031 and surrounding the diaphragm 1031, and there is a gap 1033 between the diaphragm 1031 and the retaining ring 1032,

[0086] a dressing assembly 104, including a dressing arm and a dressing head; the dressing arm drives the dressing head to close to the polishing pad 102 and swing horizontally on the polishing pad 102, and the dressing head rotates;

[0087] a liquid supply assembly 105 for supplying a polishing liquid to the surface of the polishing pad 102.

[0088] The polishing head cleaning component provided by the embodiments of the present disclosure can be used as a part of a polishing machine or an independent cleaning device. The polishing head cleaning component provides a first nozzle corresponding to the snap ring, a second nozzle corresponding to the gap, and a third nozzle corresponding to the diaphragm, so as to achieve fine cleaning of different areas of the polishing head. The second nozzle can spray high-pressure and columnar cleaning liquid and adjust the spraying angle, so as to achieve key cleaning of residues such as polishing liquid crystals and polishing by-products in the gap, reduce the residual impurities inside the polishing head, improve the adsorption force of the polishing head on the wafer, and reduce the risks of wafer slipping and fragmentation.

[0089] The above is only the specific implementation manner of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure can easily think of changes or substitutions, which should be covered within the protection scope of the present disclosure.

Claims

1. A polishing head cleaning assembly configured to align with a polishing head along a first direction and clean the polishing head, the polishing head being provided with a diaphragm and a retaining ring located at the edge of the diaphragm and surrounding the diaphragm, there being a gap between the diaphragm and the retaining ring, characterized in that, The grinding head cleaning assembly includes: A first spray head corresponding to the snap ring; A second spray head corresponding to the gap; A third spray head corresponding to the diaphragm; Wherein, the second spray head is configured to: spray columnar cleaning liquid and adjust the spraying angle.

2. The lapping head cleaning assembly according to claim 1, wherein, The grinding head cleaning assembly further includes: A first pipeline communicating with the first spray head and the third spray head; A second pipeline communicating with the second spray head; the hydraulic pressure of the second pipeline is greater than or equal to the hydraulic pressure of the first pipeline.

3. The lapping head cleaning assembly according to claim 1, wherein The third spray head is configured to spray a water curtain, and the cross-sectional shape of the water curtain along the first direction includes: A first included angle; the vertex of the first included angle is located at the liquid spraying port of the third spray head, and the two sides of the first included angle are provided by the edges of the water curtain.

4. The lapping head cleaning assembly according to claim 1, wherein The grinding head cleaning assembly further includes: A carrier plate, on which the first spray head, the second spray head and the third spray head are embedded; the liquid spraying ports of the first spray head, the second spray head and the third spray head are exposed on the surface of the carrier plate close to the grinding head.

5. The lapping head cleaning assembly according to claim 4, wherein, The liquid spraying port of the first spray head protrudes from the carrier plate by a first height, the second spray head protrudes from the carrier plate by a second height, and the third spray head protrudes from the carrier plate by a third height; wherein, the second height is greater than the first height; and / or, the second height is greater than the third height.

6. The lapping head cleaning assembly according to claim 4, wherein, The grinding head cleaning assembly further includes: A rotating shaft located below the carrier plate, and the rotating shaft drives the carrier plate to rotate in the opposite direction relative to the grinding head.

7. The lapping head cleaning assembly according to claim 4, wherein, The grinding head cleaning assembly further includes: A cavity, and the carrier plate is located in the cavity; an opening is provided on one side of the cavity close to the grinding head, and the carrier plate is exposed from the opening.

8. The lapping head cleaning assembly according to claim 4, wherein, The first spray head has a first distance from the center of the carrier plate, the second spray head has a second distance from the center of the carrier plate, and the third spray head has a third distance from the center of the carrier plate; The first distance is greater than the second distance, and the second distance is greater than the third distance.

9. The lapping head cleaning assembly according to claim 1, wherein The grinding head cleaning assembly further includes: A cleaning brush and a connecting arm connecting the cleaning brush; The connecting arm is configured to: Drive the cleaning brush to approach the grinding head and press tightly against the gap.

10. A polishing machine, characterized in that, Includes: The grinding head cleaning assembly according to any one of claims 1 to 9; The polishing machine table further includes: A grinding table for carrying a polishing pad; A grinding head; the grinding head is used to adsorb a wafer and apply pressure to the wafer to make the wafer close to the polishing pad, and the grinding head drives the wafer to rotate on the polishing pad; A dressing assembly including a dressing arm and a dressing head; the dressing arm drives the dressing head to press tightly against the polishing pad and swing horizontally on the polishing pad, and the dressing head rotates; A liquid supply assembly for providing grinding liquid to the surface of the polishing pad.

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