Square bearing head and chemical mechanical polishing system

Abstract

The invention discloses a square bearing head and a chemical mechanical polishing system, and relates to the technical field of semiconductor manufacturing. The square bearing head comprises a coupling disc; the square base is concentrically connected to the coupling disc; the loading assembly is connected to the lower portion of the square base and used for loading a substrate to be polished; the square retaining ring is arranged below the square base and located on the peripheral side of the loading assembly; the adjusting piece is connected to the square base in a sliding mode and vertically embedded into the corner of the square retaining ring, and a floating assembly is arranged above the adjusting piece so as to push the adjusting piece to move up and down; the bottom faces of the adjusting pieces abut against the outer side areas of the four corners of the base plate to drive the polishing pad to deform, so that loads of the corners of the base plate are changed, and the material removal rate of the corners of the base plate is adjusted.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and in particular to a square carrier head and a chemical mechanical polishing system. Background Technology

[0002] In semiconductor processing technology, chemical mechanical polishing (CMP) is a key process in semiconductor manufacturing and has long been widely used for global planarization of substrate surfaces. Through the synergistic effect of chemical etching and mechanical grinding, it effectively removes microscopic surface undulations, achieving ultra-flat surfaces at the nanometer to atomic level. This plays an irreplaceable role in improving the yield of multilayer wiring in integrated circuits and ensuring the accuracy of photolithography imaging.

[0003] With the rapid development of display technology, there is a demand for high-precision planarization of non-circular components, such as square glass interposers and square silicon substrates, in fields such as advanced semiconductor packaging and microelectromechanical systems (MEMS) manufacturing. In particular, the increasing demands for substrate flatness in high-resolution displays, advanced packaging, and optical component manufacturing have led to the gradual expansion of CMP technology applications to the processing of larger-sized and differently shaped substrates.

[0004] However, traditional CMP equipment and processes are primarily designed for circular substrates. Their core component—the polishing head—is typically a rotationally symmetrical circular structure, relying on a concentric multi-zone pressure adjustment system to control pressure distribution across different radial ranges during polishing. When polishing square glass substrates, this approach exhibits significant limitations: First, due to the geometric mismatch, the circular polishing head cannot completely cover the four right-angled areas of the square substrate, resulting in insufficient contact area between these areas and the polishing head, uneven pressure distribution, and thus causing inconsistent material removal rates. Secondly, during the polishing process, the right-angled area of ​​the substrate is at the edge of the rotational motion, with a large linear velocity gradient and a complex fluid dynamic environment. This makes it easier for uneven distribution of polishing fluid and accumulation of frictional heat to occur, which exacerbates the risk of over-polishing or under-polishing in this area and seriously affects the overall planarization effect. In addition, the right-angled areas of the square substrate are prone to collision with the retaining ring and break, which will affect the yield of substrate manufacturing. Summary of the Invention

[0005] In view of this, embodiments of this application provide a square bearing head and a chemical mechanical polishing system to at least partially solve the above-mentioned problems.

[0006] According to a first aspect of the embodiments of this application, a square bearing head is provided for chemical mechanical polishing of a substrate, comprising: Coupling disc; A square base, concentrically connected to the coupling disc; The mounting assembly, connected below the square base, is used to mount the substrate to be polished; A square retaining ring is positioned below the square base and on the outer periphery of the loading assembly; An adjusting component is slidably connected to a square base and vertically embedded in the corner of a square retaining ring. A floating component is disposed above the adjusting component to push the adjusting component to move up and down. The bottom surface of the adjusting component abuts against the outer area of ​​the four corners of the substrate, thereby causing the polishing pad to deform and thus changing the load on the corners of the substrate and adjusting the material removal rate at the corners of the substrate.

[0007] In some embodiments, the loading assembly includes a connecting membrane, a sealing plate, and a loading membrane; one end of the connecting membrane is connected to a square base, and the other end is connected to the sealing plate; a support plate is disposed inside the loading membrane, and both are fixed below the sealing plate.

[0008] In some embodiments, the bottom of the loading film is provided with a plurality of micropores arranged in an X-shape to vacuum-adsorb the substrate to be polished.

[0009] In some embodiments, the support plate is provided with through vents, the vents being positioned to match the micropores.

[0010] In some embodiments, the support plate is made of ceramic and has a surface configured with connecting grooves to connect a plurality of through vent holes.

[0011] In some embodiments, one end of the connecting membrane is connected between the square base and the square retaining ring, and the other end is fixed to the sealing plate by the first pressure ring to form a loading chamber; the loading chamber is provided with an inner ring membrane, which is disposed below the square base and corresponds to the position of the first pressure ring.

[0012] In some embodiments, the number of adjusting members is four, which are installed below the fixing ring; the fixing ring is slidably connected to the square base above by a guide pin, and the floating assembly drives the fixing ring and the adjusting members thereon to move in the vertical direction.

[0013] In some embodiments, the floating component includes a rolling diaphragm attached above the fixed ring, the pressurized rolling diaphragm driving the fixed ring to move vertically.

[0014] In some embodiments, the rolling film is provided with a U-shaped limiting frame inside to limit the range of expansion and contraction of the rolling film.

[0015] In some embodiments, the rolling film includes rolling ribs and an upper connecting rib. A pair of rolling ribs are symmetrically arranged along the center line of the longitudinal section of the rolling film, and the upper connecting rib is disposed at the top of the rolling ribs. A horizontal lower connecting rib is disposed between the rolling ribs, and a protrusion is disposed at the bottom of the lower connecting rib. The top surface of the fixing ring is provided with a mounting groove, and the protrusion is engaged in the mounting groove.

[0016] In some embodiments, the rolling film is a rectangular ring structure with protrusions arranged along the outline of the rolling film; the number of protrusions is a pair, and the two are spaced apart.

[0017] In some embodiments, the wall thickness of the upper connecting rib is greater than the wall thickness of the rolling rib, and the wall thickness of the rolling rib is 0.3-2mm.

[0018] In some embodiments, the square base is an annular structure with a through-groove groove on the inner side of its corner; a sealing ring is provided on the outer periphery of the adjusting member, so that the adjusting member is slidably and sealingly connected in the limiting groove.

[0019] In some embodiments, the square bearing head further includes a cover plate concentrically fitted above the square base, and the floating component is disposed between the cover plate and the square base.

[0020] In some embodiments, the square retaining ring is a rectangular ring structure with grooves on its bottom surface; the number of grooves is multiple, and they are perpendicular to the side surface of the square retaining ring and spaced apart.

[0021] In some embodiments, the bottom surface of the adjusting member is provided with an auxiliary groove, which corresponds to the position of the groove, to prevent the adjusting member from interfering with the supply of polishing fluid.

[0022] In some embodiments, the adjusting member is an L-shaped structure with its inner surface being an arc surface and / or a slope, such that the intersection line of the two inner surfaces is far away from the corner of the substrate to be polished.

[0023] In some embodiments, the square retaining ring is provided with a flushing hole that extends horizontally; the flushing hole is an oblong hole that corresponds to the sealing plate of the loading assembly.

[0024] In some embodiments, the number of flushing holes is multiple, and they are spaced apart along the contour of the square retaining ring.

[0025] According to a second aspect of the embodiments of this application, a chemical mechanical polishing system is provided, which includes a polishing disc, a liquid supply device, a trimming device, and the square bearing head described above. The square bearing head presses the substrate to be polished against a polishing pad above the polishing disc. The liquid supply device supplies polishing liquid between the polishing pad and the substrate. The trimming device is used to trim the surface of the polishing pad.

[0026] The beneficial effects of this invention include: a. A square bearing head is provided for polishing square substrates such as square glass, wherein the head is configured with an adjusting member that is slidably connected to a square base and vertically embedded in the corner of a square retaining ring to help limit the substrate to be polished; a floating component is disposed above the adjusting member to push the adjusting member to move up and down, thereby changing the load of the adjusting member against the surface of the polishing pad, adjusting the degree of elastic deformation of the polishing pad, and thereby optimizing the material removal rate of the square substrate. b. The adjustment component has an L-shaped structure with an inner surface that is curved and / or inclined, so that the intersection line of the two inner surfaces is far away from the corner of the substrate to be polished; this setting can prevent the corner of the substrate from colliding with the intersection line of the inner surfaces of the adjustment component and breaking, thereby improving the yield of substrate processing. c. The square base has a ring structure with a through-groove limiting groove on the inner side of its corner; the outer periphery of the adjusting component is equipped with a sealing ring, so that the adjusting component is slidably and sealingly connected in the limiting groove, so as to prevent polishing liquid and polishing waste liquid from entering the space where the floating component is set through the gap between the adjusting component and the limiting groove, thereby avoiding the formation of crystals in the gap and affecting the normal operation of the floating component. d. The square retaining ring is equipped with flushing holes, which are arranged horizontally to allow flushing fluid to enter the interior of the square bearing head. There are multiple flushing holes, which are spaced along the contour of the square retaining ring to ensure relatively uniform distribution of flushing fluid, thereby achieving a good flushing effect and preventing contaminants from accumulating on the surface of the square retaining ring. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0028] Figure 1 This is a schematic diagram of a square bearing head provided in an embodiment of the present invention; Figure 2 yes Figure 1 A magnified view of a section at point A in the middle; Figure 3 This is a perspective view of a square bearing head provided in an embodiment of the present invention; Figure 4 yes Figure 3 A bottom view of the square bearing head in the embodiment; Figure 5This is a partial cross-sectional view of a square bearing head provided in an embodiment of the present invention via a floating assembly and an adjusting member; Figure 6 This is a schematic diagram of an adjusting member provided in an embodiment of the present invention; Figure 7 yes Figure 4 A magnified view of a section at point B in the middle; Figure 8 A schematic diagram of a rolling film provided in an embodiment of the present invention; Figure 9 This is a longitudinal sectional view of a fixing ring provided in an embodiment of the present invention; Figure 10 This is a longitudinal sectional view of a limiting frame provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of a support plate provided in an embodiment of the present invention; Figure 12 This is a cross-sectional view of a square retaining ring provided in an embodiment of the present invention; Figure 13 This is a schematic diagram of an adjusting member with a flow-through hole according to an embodiment of the present invention; Figure 14 This is a schematic diagram of a chemical mechanical polishing system provided in an embodiment of the present invention. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0030] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0031] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0032] In this invention, "Chemical Mechanical Polishing (CMP)" is also called "Chemical Mechanical Planarization (CMP)," and the substrate is also called a wafer (W), with the same meaning and actual function.

[0033] Figure 1 This is a schematic diagram of a square bearing head 100 provided in an embodiment of the present invention, which is used for chemical mechanical polishing of a substrate. It should be noted that the substrate of the present invention is square in shape, and includes at least a square glass substrate. The square bearing head 100 includes: 10 coupling discs; A square base 20 is concentrically connected to the coupling plate 10; The loading assembly 30 is connected below the square base 20 and is used to load the substrate to be polished; A square retaining ring 40 is disposed below the square base 20 and located on the outer periphery of the loading assembly 30. The substrate to be polished is disposed inside the square retaining ring 40.

[0034] Specifically, the coupling disk 10 has a circular disk structure and is connected to the square base 20 through an annular membrane 50. A through hole is provided in the middle of the coupling disk 10. A vertically extending shaft is provided in the middle of the square base 20. The shaft can be slidably inserted into the through hole of the square base 20 and can move vertically in the through hole, thereby driving the directional base 20 and its connected loading assembly 30 to move vertically.

[0035] Figure 1 In the middle, a connecting flange (not shown) is also arranged above the coupling disk 10, which is connected to the output shaft of the drive motor to drive the square bearing head 100 to rotate around its axis, thereby driving the substrate attracted by the loading assembly 30 to rotate, so as to achieve the polishing of the substrate above the polishing pad.

[0036] Furthermore, the square bearing head 100 also includes a cover plate 60, such as Figure 1 As shown, the annular membrane 50 is concentrically fitted above the square base 20 to cover the annular membrane 50, preventing the annular membrane 50 from contacting the polishing fluid and / or polishing waste fluid, thus affecting its performance and lifespan. It should be noted that the cover plate 60 is also a square structure, and it is concentrically arranged with the square base 20, that is, the corners of the two are aligned.

[0037] Figure 2 yes Figure 1 The enlarged view at point A shows that in this embodiment, the loading assembly 30 includes a connecting membrane 31, a sealing plate 32, and a loading membrane 33. One end of the connecting membrane 31 is connected to the square base 20, and the other end is connected to the sealing plate 32. The loading membrane 33 is disposed below the sealing plate 32, and a support plate 34 is disposed inside it. The sealing plate 32 and the support plate 34 clamp the edge of the loading membrane 33, so that the loading membrane 33 covers the outside of the support plate 34.

[0038] Furthermore, one end of the connecting membrane 31 is connected between the square base 20 and the square retaining ring 40, and the other end of the connecting membrane 31 is fixed to the sealing plate 32 by the first pressure ring 35 to form the loading chamber C1. Specifically, the top surface of the square retaining ring 40 is provided with a snap-fit ​​groove, and the end of the connecting membrane 31 is disposed in the snap-fit ​​groove. Then, the square retaining ring 40 and the square base 20 are locked together by bolts, thereby abutting the connecting membrane 31 between the square retaining ring 40 and the square base 20.

[0039] An inner ring membrane 36 is provided inside the loading chamber C1, which is located below the square base 20. The inner ring membrane 36 is positioned corresponding to the first pressure ring 35, so that the expanded inner ring membrane 36 can abut against the top of the first pressure ring 35. The first pressure ring 35 is corresponding to the edge of the substrate to be polished, thereby adjusting the polishing load in the edge area of ​​the substrate and controlling the material removal rate of the substrate edge.

[0040] It is understandable that the first pressure ring 35 has a certain vertical height, and the inner ring film 36 above it can abut against the top of the first pressure ring 35 with appropriate expansion; this can improve the pressure response speed of the inner ring film 36 and enhance the uniformity of substrate polishing. At the same time, the above arrangement can also reduce the degree of vertical expansion of the inner ring film 36 and reduce the vertical dimension of the inner ring film 36, so as to reasonably arrange the various components inside the square support head 100, thereby controlling the vertical height of the directional support head 100 and improving the compactness of the internal device arrangement of the polishing unit.

[0041] Figure 3 This is a perspective view of a square bearing head 100 provided in an embodiment of the present invention. Figure 4 yes Figure 3 A bottom view of the square support head 100 in the embodiment.

[0042] The square bearing head 100 also includes an adjusting element 70. Figure 4 (As shown), the adjusting member 70 is slidably connected to the square base 20, and the adjusting member 70 is vertically embedded in the corner of the square retaining ring 40 to help limit the substrate to be polished and ensure that the substrate is relatively fixed in position.

[0043] In this invention, a floating component 80 is disposed above the adjusting member 70. Figure 5 (As shown), to push the adjusting member 70 up and down, thereby changing the load on the adjusting member 70 abutting the surface of the polishing pad and adjusting the degree of elastic deformation of the polishing pad.

[0044] Figure 5 This is a partial cross-sectional view of a square support head 100 provided in an embodiment of the present invention via a floating component 80 and an adjusting component 70. The floating component 80 is disposed between the cover plate 60 and the square base 20, and can drive the adjusting component 70 to move in the vertical direction.

[0045] Furthermore, the bottom surface of the adjusting member 70 abuts against the outer regions of the four corners of the substrate, causing the polishing pad to deform, thereby changing the load on the substrate corners and adjusting the material removal rate at the substrate corners. Specifically, in some embodiments, the adjusting member 70 moves downward, pressing against the outer regions of the four corners of the substrate, which are concave downward, while the region where the substrate corners are located convex upward, to increase the interaction force between the substrate and the polishing pad and improve the material removal rate at the substrate corners; in some embodiments, the adjusting member 70 moves upward, its force toward the polishing pad decreases, or the adjusting member 70 only contacts the polishing pad without exerting any force. In this case, the region where the substrate corners are located deforms downward from the convex state, thereby reducing the interaction force between the polishing pad and the substrate and reducing the material removal rate at the substrate corners.

[0046] Figure 7 yes Figure 4 The enlarged view at point B shows that the adjusting member 70 has an L-shaped structure with an arc-shaped inner surface, ensuring that the intersection line of the two inner surfaces is far from the corner of the substrate to be polished. This design prevents the corner of the substrate from colliding with the intersection line of the inner surfaces of the adjusting member 70 and breaking.

[0047] In some embodiments, the inner surface of the adjusting member 70 is an arc surface, and the center of the arc corresponding to the arc surface is located outside the square retaining ring 40, so that the intersection line of the two inner surfaces is far away from the corner of the substrate.

[0048] In some embodiments, the inner surface of the adjusting member 70 is beveled, and the intersection line of the two inner surfaces is away from the corner of the substrate to be polished, so as to prevent the corner of the substrate from colliding with the intersection line of the inner surfaces of the adjusting member 70 and breaking.

[0049] In some embodiments, one inner surface of the adjusting member 70 is an arc surface and the other inner surface is an inclined surface. The intersection line of the two inner surfaces is far away from the corner of the substrate to be polished, so as to prevent the corner of the substrate from colliding with the adjusting member 70 and breaking.

[0050] Figure 5 In the illustrated embodiment, the floating component 80 includes a rolling diaphragm 81 connected above the fixed ring 82, and an adjusting member 70 disposed below the fixed ring 82. The pressurized rolling diaphragm 81 drives the fixed ring 82 to move vertically, thereby causing the adjusting member 70 to move vertically.

[0051] Figure 4 In the illustrated embodiment, there are four adjusting members 70, which are installed below the retaining ring 82; the retaining ring 82 is guided by guide pins 90 ( Figure 2 (As shown) slidably connected above the square base 20, the floating assembly 80 drives the fixing ring 82 and its adjusting member 70 to move vertically. Multiple guide pins 90 are vertically disposed in the recess 22 on the upper surface of the square base 20. Figure 2 As shown in the diagram, this ensures that the fixed ring 82 and the adjusting member 70 connected to it move in the vertical direction.

[0052] Furthermore, the square base 20 has a ring-shaped structure, and its inner corner is provided with a through-type limiting groove 21, such as... Figure 5 As shown, a sealing ring 71 is provided on the outer periphery of the adjusting member 70, so that the adjusting member 70 is slidably and sealingly connected in the limiting groove 21 to prevent polishing liquid and polishing waste liquid from entering the space where the floating component 80 is set through the gap between the adjusting member 70 and the limiting groove 21.

[0053] Figure 6 This is a schematic diagram of an adjusting member provided in an embodiment of the present invention. The sealing ring 71 is disposed at the upper end of the adjusting member 70, and the sealing ring 71 is always located in the limiting groove 21 of the square base 20 to ensure a good sealing effect.

[0054] In this invention, the rolling film 81 includes rolling ribs 81a and upper connecting ribs 81b, as shown below. Figure 8 As shown, a pair of rolling ribs 81a are symmetrically arranged along the center line L of the longitudinal section of the rolling film 81, and the upper connecting rib 81b is arranged on the top of the rolling rib 81.

[0055] A horizontal lower connecting rib 81c is provided between a pair of rolling ribs 81a, and a protrusion 81d is provided at the bottom of the lower connecting rib 81c to assist in fixing the rolling film 81.

[0056] In some embodiments, the rolling film 81 is a rectangular ring structure, and the protrusions 81d thereon are arranged along the outline of the rolling film 81. Figure 8In the embodiment shown, the number of protrusions 81d is a pair, which are spaced apart and engage with the mounting groove 82a mentioned below. Figure 9 As shown in the diagram, this ensures the reliability of both being fixed.

[0057] Furthermore, the wall thickness of the upper connecting rib 81b is greater than the wall thickness of the rolling rib 81a to ensure the reliability of the rolling film 81's fixation. At the same time, the wall thickness of the rolling rib 81a should not be too small to take into account the flexibility of the rolling film 81. Preferably, the wall thickness of the rolling rib 81a is 0.3-2mm.

[0058] Figure 9 This is a longitudinal sectional view of a fixing ring 82 provided in an embodiment of the present invention. The fixing ring 82 is a rectangular ring structure. Figure 9 Only a schematic diagram of a partial longitudinal section of the fixing ring 82 is shown. The top surface of the fixing ring 82 is provided with a mounting groove 82a, and the protrusion 81d of the rolling film 81 is engaged in the mounting groove 82a to ensure the accuracy of fixing the rolling film 81 and to prevent the rolling film 81 from deviating in position under the action of external force.

[0059] Figure 5 In the floating assembly 80, a limiting frame 83 with a U-shaped longitudinal section is also included. The limiting frame 83 is disposed inside the rolling membrane 81 to limit the expansion and contraction range of the rolling membrane 81. Specifically, the main body of the limiting frame 83 is filled into the rolling membrane 81, and the inner side of the upper connecting rib 81b overlaps with the shoulder 83a of the limiting frame 83. Figure 10 (As shown), the second pressure ring 84 abuts against the outer side of the upper connecting rib 81b, and the second pressure ring 84 is fixed to the cover plate 60, thereby fixing the rolling film 81; the rolling film 81 covers the upper surface of the fixing ring 82, so that the rolling rib 81a abuts against the side of the fixing ring 82, and the protrusion 81d on the lower connecting rib 81c is engaged in the mounting groove 82a. At the same time, the third pressure ring 85 is disposed inside the limiting frame 83 and the lower connecting rib 81c, so as to install the rolling film 81 on the upper surface of the fixing ring 82.

[0060] Figure 10 This is a longitudinal sectional view of a limiting frame 83 provided in an embodiment of the present invention. In this embodiment, the limiting frame 83 includes a pair of wall plates 83b, which extend downward from the shoulder 83a, and the wall plates 83b form a space for mounting the fixing ring 82.

[0061] The wall panel 83b is disposed in the rolling rib 81a, and the length of the wall panel 83b is less than the length of the rolling rib 81a, so that the rolling rib 81a can move within a certain range. In some embodiments, the distance between the inner bottom surface of the rolling rib 81a and the bottom surface of the wall panel 83b is 3-10 mm, so as to limit the vertical movement distance of the rolling film 81.

[0062] Furthermore, the limit frame 83 is also equipped with floating air holes 83c, such as Figure 10 As shown, it communicates with the chamber formed by the rolling film 81 to inflate or deflate the rolling film 81, thereby adjusting the air pressure of the rolling film 81 and driving the adjusting member 70 to move in the vertical direction.

[0063] In this invention, the substrate to be polished is adsorbed onto the bottom of the loading film 33 by negative pressure. To ensure vacuum adsorption of the substrate, the bottom of the loading film 33 is provided with through-holes 33a, such as... Figure 4 As shown, there are multiple micropores 33a arranged in an X-shape to distribute the adsorption force along the diagonal of the substrate to be polished, ensuring the reliability of adsorption.

[0064] To ensure unobstructed airflow through the adsorption substrate, the support plate 34 is also equipped with through-holes 34a, such as... Figure 11 As shown, the vent 34a is positioned to match the micropores 33a of the loading membrane 33, so that fluids such as gas are transported downward through the micropores 33a and the vent 34a.

[0065] In some embodiments, the support plate 34 is made of ceramic, and its surface is configured with... Figure 11 The connecting groove 34b shown connects multiple through vent holes 34a. The ceramic material has good processing precision and high hardness, resulting in extremely high positioning accuracy between the loading assembly 30 and the substrate, ensuring that the square bearing head 100 accurately applies the polishing load.

[0066] Specifically, the connecting groove 34b includes an inclined groove and a transverse and longitudinal groove. The inclined groove is provided through a vent 34a, while the transverse and longitudinal grooves are provided in the transverse or longitudinal direction, so that the inclined grooves are interconnected, thereby ensuring that the fluid entering through the air passage can be quickly dispersed, and the fluid contacts the back side of the substrate through the vent 34a and the micropore 33a.

[0067] In this invention, the square retaining ring 40 is a rectangular ring structure, such as... Figure 4 As shown, its bottom surface is provided with grooves 41; there are multiple grooves 41, and adjacent grooves 41 are spaced apart. The grooves 41 are perpendicular to the side of the square retaining ring 40, so that the polishing liquid can enter the interior of the square bearing head 100 through the grooves 41 below the square retaining ring 40. At the same time, the used polishing liquid (polishing waste liquid) is discharged from the square bearing head 100 through the grooves 41.

[0068] Furthermore, the bottom surface of the adjusting member 70 is provided with an auxiliary groove 72, such as... Figure 6 and 7 As shown, it corresponds to the position of the groove 41, so that the polishing liquid or polishing waste liquid can enter or exit the square bearing head 100 through the groove 41 and the auxiliary groove 72, so as to prevent the adjustment member 70 from interfering with the supply of polishing liquid.

[0069] In this invention, the square retaining ring 40 is provided with a flushing hole 42, such as... Figure 3 and Figure 12 As shown, the flushing hole 42 is arranged horizontally, and the flushing fluid can enter the interior of the square bearing head 100 through the flushing hole 42 to flush the particles attached to the outer surface of the loading assembly 30, and prevent the particles from crystallizing and falling off, causing scratches and defects.

[0070] Furthermore, the flushing hole 42 is an oblong hole, which corresponds to the sealing plate 32 of the loading assembly 30, such as... Figure 12 As shown, polishing particles and waste liquid adhering to the outer periphery of the loading assembly 30 are removed in a timely manner to prevent crystal formation on the outer periphery of the loading assembly 30 and thus prevent scratches on the substrate.

[0071] Especially in the area where the sealing plate 32 connects to the loading membrane 33, the loading membrane 33 is larger than the sealing plate 32, forming a stepped structure. Due to the different materials used in their manufacture, polishing contaminants will generate tiny eddies or flow stagnation zones at the corners of this stepped structure. During polishing, the loading assembly 30 rotates at high speed around its axis. The flow velocity in these micro-eddies and stagnation zones is much lower than in other areas. When the fluid carrying polishing contaminants enters these areas, the contaminant particles or molecules have a longer residence time and interact with the surface. The contaminant particles are difficult to be carried away by the high-speed mainstream liquid flow in time, thus continuously accumulating in these areas. When the concentration exceeds its solubility limit, crystallization begins.

[0072] To address the aforementioned issues, the flushing hole 42 of this application is positioned at the contact point between the sealing plate 32 and the loading film 33 to specifically clean polishing contaminants in that area, prevent the formation of micro-eddies and stagnant areas at the corners of the stepped structure, and prevent crystal formation in that area that could lead to scratches on the substrate.

[0073] In some embodiments, there are multiple flushing holes 42, which are spaced apart along the contour of the square retaining ring 40 to ensure that the flushing fluid is distributed relatively evenly, thereby achieving a good flushing effect.

[0074] In some embodiments, the flushing hole 42 is located at the corner of the square retaining ring 40 to spray cleaning fluid toward the corners of the sealing plate 32 and the loading membrane 33, preventing particulate matter accumulation. Since the adjusting member 70 is located at the corner of the square bearing head 100, it obstructs the flow direction of the cleaning fluid; therefore, a flow-through hole 73 needs to be provided at a corresponding position on the adjusting member 70, such as... Figure 13 As shown, this allows the sprayed cleaning fluid to reach the corners of the sealing plate 32 and the loading membrane 33 via the flushing hole 42 and the flow hole 73 at the corners, preventing contaminants from remaining there and forming crystals.

[0075] In some embodiments, the shape of the flushing hole 42 is the same as that of the flow through hole 73, but the size of the flushing hole 42 is larger than that of the flow through hole 73, so that the cleaning fluid through the flushing hole 42 is sprayed onto the outer wall of the regulating member 70 to clean the contaminants between the regulating member 70 and the square retaining ring 40 by the splashing of the liquid, and to prevent particulate matter from accumulating in the gap between the two and forming crystals.

[0076] In addition, the present invention also provides a chemical mechanical polishing system 1000, the schematic diagram of which is shown below. Figure 14 As shown, the chemical mechanical polishing system 1000 includes a polishing disc 200, a polishing pad 300, a dressing device 400, a liquid supply device 500, and... Figure 1 The square bearing head 100 is shown.

[0077] The polishing pad 300 is disposed on the upper surface of the polishing disk 200 and rotates together with it along the axis Ax; the horizontally movable square support head 100 is disposed above the polishing pad 300, and the substrate to be polished is loaded on its lower surface; the trimming device 400 includes a trimming arm and a trimming head, which is disposed on one side of the polishing disk 200, and the trimming arm drives the rotating trimming head to swing to trim the surface of the polishing pad 300; the liquid supply device 500 is disposed on the upper side of the polishing pad 300 to distribute the polishing liquid on the surface of the polishing pad 300.

[0078] During the polishing operation, the square bearing head 100 presses the surface of the substrate to be polished against the surface of the polishing pad 300. The square bearing head 100 rotates and reciprocates radially along the polishing disc 200, gradually removing impurities from the substrate surface in contact with the polishing pad 300. Simultaneously, the polishing disc 200 rotates, and the liquid supply device 500 sprays polishing liquid onto the surface of the polishing pad 300. Under the chemical action of the polishing liquid, the relative movement between the square bearing head 100 and the polishing disc 200 causes the substrate to rub against the polishing pad 300, thus achieving polishing.

[0079] During chemical mechanical polishing, the dressing device 400 is used to dress and activate the surface morphology of the polishing pad 300. Using the dressing device 400, impurity particles remaining on the surface of the polishing pad, such as abrasive particles in the polishing slurry and waste material detached from the substrate surface, can be removed. It can also smooth out the surface deformation of the polishing pad 300 caused by abrasion, ensuring the consistency of the surface morphology of the polishing pad 300 during polishing, thereby maintaining a stable polishing removal rate.

[0080] In this embodiment, the square bearing head 100 is equipped with an adjustment member 70, and the floating component 80 connected thereto drives the adjustment member 70 to move vertically through the inner pressure ring 82, so as to adjust the degree of rebound of the polishing pad acting on the outer area of ​​the corner of the substrate, thereby changing the force situation of the corner of the substrate and controlling the polishing removal rate of the corner of the substrate.

[0081] Meanwhile, the adjusting member 70 has an L-shaped structure, with its inner surface being an arc surface and / or a slope, so that the intersection line of the two inner surfaces is far away from the corner of the substrate to be polished. This design can prevent the corner of the substrate from colliding with the intersection line of the inner surfaces of the adjusting member 70 and breaking.

[0082] Those skilled in the art will recognize that the units and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of this application.

[0083] The above embodiments are only used to illustrate the embodiments of this application, and are not intended to limit the embodiments of this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of this application. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of this application, and the patent protection scope of the embodiments of this application should be defined by the claims.

Claims

1. A square bearing head for chemical mechanical polishing of substrates, characterized in that, include: Coupling disc; A square base, concentrically connected to the coupling disc; The mounting assembly, connected below the square base, is used to mount the substrate to be polished; A square retaining ring is positioned below the square base and on the outer periphery of the loading assembly; An adjusting component is slidably connected to a square base and vertically embedded in the corner of a square retaining ring. A floating component is disposed above the adjusting component to push the adjusting component to move up and down. The bottom surface of the adjusting component abuts against the outer area of ​​the four corners of the substrate, thereby causing the polishing pad to deform and thus changing the load on the corners of the substrate and adjusting the material removal rate at the corners of the substrate.

2. The square bearing head according to claim 1, characterized in that, The loading assembly includes a connecting membrane, a sealing plate, and a loading membrane; one end of the connecting membrane is connected to a square base, and the other end is connected to the sealing plate; a support plate is provided inside the loading membrane, and both are fixed below the sealing plate.

3. The square bearing head according to claim 2, characterized in that, The bottom of the loading film is provided with multiple micropores arranged in an X-shape to vacuum adsorb the substrate to be polished.

4. The square bearing head according to claim 3, characterized in that, The support plate is provided with through vent holes, and the vent holes are matched with the positions of the micropores.

5. The square bearing head according to claim 3, characterized in that, The support plate is made of ceramic and has a surface with connecting grooves to connect multiple through vent holes.

6. The square bearing head according to claim 2, characterized in that, One end of the connecting membrane is connected between the square base and the square retaining ring, and the other end is fixed to the sealing plate by the first pressure ring to form a loading chamber; the loading chamber is provided with an inner ring membrane, which is located below the square base and corresponds to the position of the first pressure ring.

7. The square bearing head according to claim 1, characterized in that, The number of adjusting components is four, which are installed below the fixed ring; the fixed ring is slidably connected to the upper part of the square base through a guide pin, and the floating component drives the fixed ring and the adjusting components on it to move in the vertical direction.

8. The square bearing head according to claim 7, characterized in that, The floating component includes a rolling membrane connected above the fixed ring, and the pressurized rolling membrane drives the fixed ring to move vertically.

9. The square bearing head according to claim 8, characterized in that, The rolling film is equipped with a U-shaped limiting frame inside to limit the range of expansion and contraction of the rolling film.

10. The square bearing head according to claim 9, characterized in that, The rolling film includes rolling ribs and upper connecting ribs. A pair of rolling ribs are symmetrically arranged along the center line of the longitudinal section of the rolling film. The upper connecting rib is located at the top of the rolling ribs. A horizontal lower connecting rib is provided between the rolling ribs. The bottom of the lower connecting rib is provided with a protrusion. The top surface of the fixing ring is provided with a mounting groove, and the protrusion is engaged in the mounting groove.

11. The square bearing head according to claim 10, characterized in that, The rolling film has a rectangular ring structure, and the protrusions on it are arranged along the outline of the rolling film; the number of protrusions is a pair, and the two are arranged at intervals.

12. The square bearing head according to claim 10, characterized in that, The wall thickness of the upper connecting rib is greater than the wall thickness of the rolling rib, and the wall thickness of the rolling rib is 0.3-2mm.

13. The square bearing head according to claim 1, characterized in that, The square base has a ring-shaped structure, and a through-type limiting groove is provided on the inner side of its corner; a sealing ring is provided on the outer periphery of the adjusting member, so that the adjusting member is slidably and sealingly connected in the limiting groove.

14. The square bearing head according to claim 1, characterized in that, It also includes a cover plate, which is concentrically fitted above the square base, and the floating component is disposed between the cover plate and the square base.

15. The square bearing head according to claim 2, characterized in that, The square retaining ring is a rectangular ring structure with grooves on its bottom surface; there are multiple grooves, which are perpendicular to the side surface of the square retaining ring and spaced apart.

16. The square bearing head according to claim 15, characterized in that, The bottom surface of the adjusting component is provided with an auxiliary groove, which corresponds to the position of the groove, in order to prevent the adjusting component from interfering with the supply of polishing fluid.

17. The square bearing head according to claim 1, characterized in that, The adjusting member has an L-shaped structure, with its inner surface being an arc surface and / or a slope, so that the intersection line of the two inner surfaces is far away from the corner of the substrate to be polished.

18. The square bearing head according to claim 15, characterized in that, The square retaining ring is provided with a flushing hole that runs horizontally through it; the flushing hole is an oblong hole that corresponds to the sealing plate of the loading assembly.

19. The square bearing head according to claim 18, characterized in that, The number of flushing holes is multiple, and they are spaced apart along the outline of the square retaining ring.

20. A chemical mechanical polishing system, characterized in that, The device includes a polishing disc, a liquid supply device, a trimming device, and a square bearing head as described in any one of claims 1 to 19. The square bearing head presses the substrate to be polished against a polishing pad above the polishing disc. The liquid supply device supplies polishing liquid between the polishing pad and the substrate. The trimming device is used to trim the surface of the polishing pad.

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