A square carrier head and chemical mechanical polishing system

Abstract

The application discloses a square carrier head and a chemical mechanical polishing system, and relates to the technical field of semiconductor manufacturing. The square carrier head comprises a coupling disc, a square base connected concentrically to the coupling disc, a loading assembly connected below the square base and used for loading a substrate to be polished, a square retaining ring arranged below the square base and located at the outer circumferential side of the loading assembly, and an adjusting piece slidingly connected to the square base and vertically embedded in the corner of the square retaining ring. A floating assembly is arranged above the adjusting piece to push the adjusting piece to move up and down. The bottom surface of the adjusting piece abuts against the outer side area of the four corners of the substrate to drive the deformation of a polishing pad, so that the load of the corner of the substrate is changed to adjust the material removal rate of the corner of the substrate.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of semiconductor manufacturing, and in particular, to a square carrier head and a chemical mechanical polishing system. BACKGROUND

[0002] In the semiconductor processing technology, the chemical mechanical polishing (CMP) technology as a key process in semiconductor manufacturing has been widely used in global planarization processing of substrate surface for a long time. Through the synergistic effect of chemical corrosion and mechanical grinding, it effectively removes the surface micro-relief to realize the nanometer to atomic level ultra-smooth surface, which plays an irreplaceable role in improving the yield of multi-layer wiring of integrated circuits and ensuring the precision of lithography imaging.

[0003] With the rapid development of display technology, there is also a demand for high-precision planarization of non-circular components such as square glass interposers and square silicon substrates in the fields of advanced semiconductor packaging and micro-electro-mechanical system manufacturing. Especially with the increasing demand for substrate flatness in high-resolution display screens, advanced packaging and optical element manufacturing, the application scenarios of CMP technology have gradually extended to the field of processing larger size and different shape substrates.

[0004] However, the traditional CMP equipment and process are mainly designed for circular substrates, and the polishing head, which is the core component, is usually a rotationally symmetric circular structure. In the polishing process, it relies on a concentric multi-zone pressure adjustment system to control the pressure distribution in different radial ranges. When polishing square glass substrates, such a scheme presents significant inadaptability:

[0005] Firstly, due to the geometric mismatch of the shape, the circular polishing head cannot completely cover the four right-angle areas of the square substrate, resulting in insufficient contact area and uneven pressure distribution in these areas, which in turn causes inconsistent material removal rate;

[0006] Secondly, during the polishing process, the right-angle areas of the substrate are at the edge position of the rotating motion, with large linear velocity gradient and complex fluid dynamics environment, which makes it more likely to have uneven distribution of polishing liquid and accumulation of friction heat, etc., aggravating the risk of over-polishing or under-polishing in this area, and seriously affecting the effect of global planarization;

[0007] In addition, the right-angle areas of the square substrate are prone to collision with the retaining ring and breakage, which will affect the yield of the substrate manufacturing. SUMMARY

[0008] Therefore, embodiments of the present application provide a square carrier head and a chemical mechanical polishing system to at least partially solve the above problems.

[0009] According to a first aspect of the embodiments of the present application, a square carrier head for chemical mechanical polishing of a substrate is provided, comprising:

[0010] a coupling disc;

[0011] a square base connected concentrically to the coupling disc;

[0012] a loading assembly connected below the square base for loading the substrate to be polished;

[0013] a square retaining ring arranged below the square base and at the outer circumferential side of the loading assembly;

[0014] an adjusting member slidingly connected to the square base and vertically embedded into the corner of the square retaining ring, wherein an upper portion of the adjusting member is configured with a floating assembly to push the adjusting member to move up and down, and a bottom surface of the adjusting member abuts against the outer side area of the four corners of the substrate to drive the polishing pad to deform, so as to change the load of the corner of the substrate and adjust the material removal rate of the corner of the substrate.

[0015] In some embodiments, the loading assembly comprises a connecting film, a sealing plate and a loading film; one end of the connecting film is connected to the square base, and the other end is connected to the sealing plate; the inside of the loading film is provided with a support plate, both of which are fixed below the sealing plate.

[0016] In some embodiments, the bottom of the loading film is configured with a plurality of micropores arranged in an X shape to vacuum adsorb the substrate to be polished.

[0017] In some embodiments, the support plate is configured with through air holes matching the arrangement positions of the micropores.

[0018] In some embodiments, the support plate is made of ceramic, and the surface thereof is configured with a communication groove to connect a plurality of through air holes.

[0019] In some embodiments, one end of the connecting film is connected between the square base and the square retaining ring, and the other end is fixed to the sealing plate by a first compression ring to form a loading chamber; the inside of the loading chamber is provided with an inner ring film arranged below the square base and corresponding to the position of the first compression ring.

[0020] In some embodiments, the number of adjusting members is four, which are installed below a fixed ring; the fixed ring is slidingly connected to the upper portion of the square base by a guide pin, and the floating assembly drives the fixed ring and the adjusting members thereon to move in the vertical direction.

[0021] In some embodiments, the floating assembly comprises a rolling film connected to the upper portion of the fixed ring, and the pressurized rolling film drives the fixed ring to move vertically.

[0022] In some embodiments, the inner part of the rolling film is provided with a limiting frame with a U-shaped cross section to limit the rolling film's expansion and contraction range.

[0023] In some embodiments, the rolling film comprises 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 arranged on the top of the rolling rib; a horizontal lower connecting rib is arranged between the rolling ribs, and 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 clamped in the mounting groove.

[0024] In some embodiments, the rolling film is a rectangular ring structure, and the protrusions are arranged along the contour line of the rolling film; the number of protrusions is a pair, and the two protrusions are spaced apart.

[0025] 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.

[0026] In some embodiments, the square base is a ring structure, and the inner side of the corner part is provided with a through limiting groove; the outer circumferential side of the adjusting member is provided with a sealing ring, so that the adjusting member is slidingly and sealingly connected in the limiting groove.

[0027] In some embodiments, the square bearing head further comprises a cover plate concentrically arranged above the square base, and the floating assembly is arranged between the cover plate and the square base.

[0028] In some embodiments, the square retaining ring is a rectangular ring structure, and the bottom surface is provided with a groove; the number of grooves is multiple, and the grooves are perpendicular to the side surface of the square retaining ring and are spaced apart.

[0029] In some embodiments, the bottom surface of the adjusting member is provided with an auxiliary groove corresponding to the position of the groove to prevent the adjusting member from interfering with the supply of polishing liquid.

[0030] In some embodiments, the adjusting member is an L-shaped structure, and the inner side surface is an arc surface and / or an inclined surface, so that the intersection line of the two inner side surfaces is away from the corner part of the substrate to be polished.

[0031] In some embodiments, the square retaining ring is provided with a flushing hole arranged in the horizontal direction; the flushing hole is a waist-shaped hole corresponding to the sealing plate of the loading assembly.

[0032] In some embodiments, the number of flushing holes is multiple, and the flushing holes are spaced apart along the contour of the square retaining ring.

[0033] According to a second aspect of the embodiments of the present application, a chemical mechanical polishing system is provided, which comprises a polishing disc, a liquid supply device, a dressing device and the square carrier head described above, the square carrier head presses the substrate to be polished against the polishing pad above the polishing disc, the liquid supply device supplies polishing liquid towards the polishing pad and the substrate, and the dressing device is used to dress the surface of the polishing pad.

[0034] The beneficial effects of the present application include:

[0035] a. A square carrier head is provided for polishing of square substrates such as square glass, which is provided with an adjusting piece that is slidingly connected to the square base and vertically embedded in the corner of the square retaining ring to assist in defining the substrate to be polished; a floating assembly is arranged above the adjusting piece to push the adjusting piece up and down, thereby changing the load of the adjusting piece abutting 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;

[0036] b. The adjusting piece is of L-shaped structure, and the inner side surface is arc-shaped and / or beveled, so that the intersection line of the two inner side surfaces is away from the corner of the substrate to be polished; in this way, the corner of the substrate can be prevented from being broken by colliding with the intersection line of the inner side surfaces of the adjusting piece, thereby improving the yield of substrate processing;

[0037] c. The square base is of ring structure, and the inner side of the corner is provided with a through limiting groove; the outer periphery of the adjusting piece is provided with a sealing ring, so that the adjusting piece is slidingly and sealingly connected in the limiting groove, to prevent the polishing liquid and the waste liquid generated by polishing from entering the space where the floating assembly is arranged through the gap between the adjusting piece and the limiting groove, thereby avoiding the formation of crystals in the gap and affecting the normal operation of the floating assembly;

[0038] d. The square retaining ring is provided with a plurality of flushing holes that are arranged along the contour of the square retaining ring and are spaced apart to ensure relatively uniform distribution of the flushing liquid, thereby achieving good flushing effect and preventing pollutants from accumulating on the surface of the square retaining ring. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0040] Figure 1 is a schematic view of a square carrier head provided by an embodiment of the present application;

[0041] Figure 2 yes Figure 1 A magnified view of a section at point A in the middle;

[0042] Figure 3 This is a perspective view of a square bearing head provided in an embodiment of the present invention;

[0043] Figure 4 yes Figure 3 A bottom view of the square bearing head in the embodiment;

[0044] Figure 5 This 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;

[0045] Figure 6 This is a schematic diagram of an adjusting member provided in an embodiment of the present invention;

[0046] Figure 7 yes Figure 4 A magnified view of a section at point B in the middle;

[0047] Figure 8 A schematic diagram of a rolling film provided in an embodiment of the present invention;

[0048] Figure 9 This is a longitudinal sectional view of a fixing ring provided in an embodiment of the present invention;

[0049] Figure 10 This is a longitudinal sectional view of a limiting frame provided in an embodiment of the present invention;

[0050] Figure 11 This is a schematic diagram of a support plate provided in an embodiment of the present invention;

[0051] Figure 12 This is a cross-sectional view of a square retaining ring provided in an embodiment of the present invention;

[0052] Figure 13 This is a schematic diagram of an adjusting member with a flow-through hole according to an embodiment of the present invention;

[0053] Figure 14 This is a schematic diagram of a chemical mechanical polishing system provided in an embodiment of the present invention. Detailed Implementation

[0054] 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 the 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.

[0055] The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in the description of the application and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It also will be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0056] It should be understood that although the terms "first", "second", "third" etc. can be employed in the present application to describe various information, such information should not be limited by these terms. These terms are only used to distinguish one piece of information from another. For example, a first information can also be termed a second information, and similarly, a second information can also be termed a first information without departing from the scope of the present application. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0057] In the present application, "Chemical Mechanical Polishing (CMP)" is also referred to as "Chemical Mechanical Planarization (CMP)", and "substrate" is also referred to as "wafer (W)", and the meanings and actual effects are the same.

[0058] Figure 1 is a schematic view of a square carrier head 100 provided by an embodiment of the present application, which is used for chemical mechanical polishing of a substrate. It should be noted that the substrate of the present application is square in shape, and at least includes a square glass substrate. The square carrier head 100 includes:

[0059] a coupling disc 10;

[0060] a square base 20, which is connected concentrically to the coupling disc 10;

[0061] a loading assembly 30, which is connected below the square base 20, and is used for loading a substrate to be polished;

[0062] a square retaining ring 40, which is arranged below the square base 20 and at the outer circumferential side of the loading assembly 30. The substrate to be polished is arranged inside the square retaining ring 40.

[0063] Specifically, the coupling disc 10 is a circular disc structure, which is connected with the square base 20 through the annular film 50, and the middle part of the coupling disc 10 is provided with a through hole; the middle part of the square base 20 is provided with a vertically extending shaft part, which is slidably inserted into the through hole of the square base 20, and the shaft part can move in the vertical direction in the through hole, thereby driving the square base 20 and the connected loading assembly 30 to move vertically.

[0064] Figure 1 In this embodiment, the upper part of the coupling disc 10 is also provided with a connection flange which is not shown, which is connected with the output shaft of the driving 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 to realize the polishing of the substrate above the polishing pad.

[0065] Further, the square bearing head 100 also includes a cover plate 60, as shown, which is concentrically arranged above the square base 20 to cover the annular film 50 to prevent the annular film 50 from being contacted with the polishing liquid and / or polishing waste liquid to affect its performance and service life. It should be noted that the cover plate 60 is also a square structure, which is arranged concentrically with the square base 20, i.e. the corners of the two are arranged in alignment. Figure 1

[0066] Figure 2 Figure 1 In this embodiment, the loading assembly 30 includes a connecting film 31, a sealing plate 32 and a loading film 33, wherein one end of the connecting film 31 is connected to the square base 20, and the other end is connected to the sealing plate 32; the loading film 33 is arranged below the sealing plate 32, and the inside of the loading film 33 is provided with a support plate 34, and the sealing plate 32 and the support plate 34 clamp the edges of the loading film 33, so that the loading film 33 is arranged outside the support plate 34.

[0067] Further, one end of the connecting film 31 is connected between the square base 20 and the square retaining ring 40, and the other end of the connecting film 31 is fixed to the sealing plate 32 by the first compression ring 35 to form a loading chamber C1. Specifically, the top surface of the square retaining ring 40 is provided with a clamping groove, and the end of the connecting film 31 is arranged in the clamping groove, and then the square retaining ring 40 and the square base 20 are locked by bolts, and the connecting film 31 is abutted between the square retaining ring 40 and the square base 20.

[0068] The inside of the loading chamber C1 is provided with an inner ring film 36, which is arranged below the square base 20, and the position of the inner ring film 36 corresponds to that of the first compression ring 35, so that the expanded inner ring film 36 can abut above the first compression ring 35, and the first compression ring 35 corresponds to the edge of the substrate to be polished, thereby adjusting the polishing load of the edge area of the substrate and controlling the material removal rate of the edge of the substrate.

[0069] ​​It can be understood that the first compression ring 35 has a certain vertical height, and the inner ring film 36 at the top is abutted to the top of the first compression ring 35 by appropriate expansion; this can improve the pressure response speed of the inner ring film 36 and improve the uniformity of the substrate polishing. At the same time, the above-mentioned setting can also reduce the vertical expansion degree of the inner ring film 36, reduce the size of the inner ring film 36 in the vertical direction, reasonably arrange each component inside the square carrier head 100, and then control the vertical height of the square carrier head 100, so as to improve the compactness of the arrangement of the internal devices of the polishing unit.

[0070] Figure 3 is a perspective view of the square carrier head 100 provided by an embodiment of the present application, Figure 4 is Figure 3 is a bottom view of the square carrier head 100 in the embodiment.

[0071] The square carrier head 100 further comprises an adjusting piece 70 Figure 4 is shown, the adjusting piece 70 is slidingly connected to the square base 20, and the adjusting piece 70 is vertically embedded in the corner of the square retaining ring 40 to assist in defining the substrate to be polished and ensuring that the setting position of the substrate is relatively fixed.

[0072] In the present application, the upper side of the adjusting piece 70 is provided with a floating assembly 80 Figure 5 is shown, to push the adjusting piece 70 to move up and down, and then change the load of the adjusting piece 70 abutting to the surface of the polishing pad, and adjust the degree of elastic deformation of the polishing pad.

[0073] Figure 5 is a partial sectional view of the square carrier head 100 provided by an embodiment of the present application via the floating assembly 80 and the adjusting piece 70, the floating assembly 80 is arranged between the cover plate 60 and the square base 20, and can drive the adjusting piece 70 to move in the vertical direction.

[0074] Further, the bottom surface of the adjusting piece 70 abuts to the outer side area of the four corners of the substrate to drive the polishing pad to deform, so as to change the material removal rate of the corner of the substrate. Specifically, in some embodiments, the adjusting piece 70 moves downward and abuts to the outer side area of the four corners of the substrate, the outer side area is recessed downward, and the area where the corner of the substrate is located is convex upward, so as to increase the interaction force between the polishing pad and the substrate and improve the material removal rate of the corner of the substrate; in some embodiments, the adjusting piece 70 moves upward, the force acting on the polishing pad becomes smaller, or the adjusting piece 70 only contacts the polishing pad without force, at this time, the area where the corner of the substrate is located is deformed downward from the convex state, and then the interaction force between the polishing pad and the substrate is reduced, and the material removal rate of the corner of the substrate is reduced.

[0075] Figure 7 is Figure 4The local enlarged view at the middle B shows that the adjusting member 70 is L-shaped structure, and the inner side surface is arc surface, so that the intersection line of the two inner side surfaces is away from the corner of the substrate to be polished. In this way, the corner of the substrate can be prevented from being broken by colliding with the intersection line of the inner side surfaces of the adjusting member 70.

[0076] In some embodiments, the inner side surface of the adjusting member 70 is arc surface, and the center of the arc corresponding to the arc surface is located outside the square holding ring 40, so that the intersection line of the two inner side surfaces is away from the corner of the substrate.

[0077] In some embodiments, the inner side surface of the adjusting member 70 is inclined surface, and the intersection line of the two inner side surfaces is away from the corner of the substrate to be polished, so that the corner of the substrate can be prevented from being broken by colliding with the intersection line of the inner side surfaces of the adjusting member 70.

[0078] In some embodiments, one inner side surface of the adjusting member 70 is arc surface, and the other inner side surface is inclined surface, and the intersection line of the two inner side surfaces is away from the corner of the substrate to be polished, so that the corner of the substrate can be prevented from being broken by colliding with the adjusting member 70.

[0079] Figure 5 In the shown embodiment, the floating assembly 80 includes a rolling film 81 connected to the upper side of a fixed ring 82, and the adjusting member 70 is arranged below the fixed ring 82. The rolling film 81 under pressure drives the fixed ring 82 to move vertically, so as to drive the adjusting member 70 to move vertically.

[0080] Figure 4 In the shown embodiment, the number of the adjusting member 70 is four, which is arranged below the fixed ring 82. The fixed ring 82 is slidably connected to the upper side of the square base 20 through a guide pin 90 (shown), and the floating assembly 80 drives the fixed ring 82 and the adjusting member 70 thereon to move vertically. Figure 2 The number of the guide pin 90 is multiple, which is vertically arranged in the recess 22 (shown) on the upper surface of the square base 20, so as to ensure the vertical movement of the fixed ring 82 and the adjusting member 70 connected thereto. Figure 2

[0081] Further, the square base 20 is ring structure, and the inner side of the corner is provided with a through limiting groove 21, as shown. Figure 5 The outer periphery of the adjusting member 70 is provided with a sealing ring 71, so that the adjusting member 70 is slidably and sealingly connected in the limiting groove 21, so as to prevent the polishing liquid and the waste liquid generated by polishing from entering the space provided by the floating assembly 80 through the gap between the adjusting member 70 and the limiting groove 21.

[0082] Figure 6 The shown is the schematic view of the adjusting member provided by an embodiment of the present application. The sealing ring 71 is arranged 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, so as to ensure good sealing effect.​

[0083] In the present application, the rolling film 81 comprises rolling ribs 81a and upper connecting ribs 81b, 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 ribs 81b are arranged on the top of the rolling ribs 81. Figure 8

[0084] A horizontal lower connecting rib 81c is arranged between the pair of rolling ribs 81a, and the bottom of the lower connecting rib 81c is provided with a protrusion 81d to assist the fixation of the rolling film 81.

[0085] In some embodiments, the rolling film 81 is a rectangular ring structure, and the protrusions 81d thereon are arranged along the contour line of the rolling film 81. Figure 8 In the embodiment shown, the number of protrusions 81d is a pair, which are spaced apart and clamped in the mounting groove 82a (shown below) to ensure the reliability of the fixation. Figure 9

[0086] Further, the wall thickness of the upper connecting rib 81b is greater than that of the rolling rib 81a to ensure the reliability of the fixation of the rolling film 81, and the wall thickness of the rolling rib 81a is not 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.

[0087] Figure 9 is a longitudinal sectional view of the fixing ring 82 provided by an embodiment of the present application, the fixing ring 82 is a rectangular ring structure, Figure 9 only shows a schematic view of part of the longitudinal section of the fixing ring 82. 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 clamped in the mounting groove 82a to ensure the accuracy of the fixation of the rolling film 81 and avoid the position deviation of the rolling film 81 under external force.

[0088] Figure 5 In the present application, the floating assembly 80 further comprises a limiting frame 83, the longitudinal section of which is U-shaped, and the limiting frame 83 is arranged inside the rolling film 81 to limit the deformation amplitude of the rolling film 81. Specifically, the main body part of the limiting frame 83 is filled in the rolling film 81, the inner side surface of the upper connecting rib 81b is overlapped on the shoulder part 83a (shown below) of the limiting frame 83, the second compression ring 84 is abutted to the outer side surface of the upper connecting rib 81b, and the second compression ring 84 is fixed to the cover plate 60, thereby realizing the fixation of the rolling film 81; the rolling film 81 is wrapped on the upper surface of the fixing ring 82, so that the rolling rib 81a is abutted to the side surface of the fixing ring 82, the protrusion 81d on the lower connecting rib 81c is clamped in the mounting groove 82a, and the third compression ring 85 is arranged inside the limiting frame 83 and the lower connecting rib 81c to mount the rolling film 81 on the upper surface of the fixing ring 82. Figure 10

[0089] ​​​Figure 10 is a longitudinal sectional view of the limiting frame 83 provided by an embodiment of the present application, in which the limiting frame 83 comprises a pair of wall plates 83b extending downward from the shoulder 83a, and the wall plates 83b form a space for mounting the fixing ring 82.

[0090] The wall plates 83b are arranged in the rolling ribs 81a, and the length of the wall plates 83b is less than the length of the rolling ribs 81a, so that the rolling ribs 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 plate 83b is 3-10 mm, so as to limit the up-down movement distance of the rolling film 81.

[0091] Further, the limiting frame 83 is also provided with a floating air hole 83c, which is in communication with the cavity formed by the rolling film 81, so as 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 along the vertical direction. Figure 10

[0092] In the present application, the substrate to be polished is adsorbed on the bottom of the loading film 33 by negative pressure. In order to ensure the vacuum adsorption of the substrate, the bottom of the loading film 33 is provided with a plurality of through micro-holes 33a, as shown in the figure, and the micro-holes 33a are arranged in an X shape, so as to distribute the adsorption force along the diagonal line of the substrate to be polished, and ensure the reliability of the adsorption. Figure 4

[0093] In order to ensure the smoothness of the gas path for adsorbing the substrate, the support plate 34 is also provided with a plurality of through air holes 34a, as shown in the figure, and the positions of the air holes 34a are matched with the positions of the micro-holes 33a of the loading film 33, so that the fluid such as gas can be transmitted downward through the micro-holes 33a and the air holes 34a. Figure 11

[0094] In some embodiments, the support plate 34 is made of ceramic, and the surface of the support plate 34 is provided with a plurality of through air holes 34a, as shown in the figure, and the positions of the air holes 34a are matched with the positions of the micro-holes 33a of the loading film 33, so that the fluid such as gas can be transmitted downward through the micro-holes 33a and the air holes 34a. Figure 11

[0095] Specifically, the communication grooves 34b include diagonal grooves and horizontal and vertical grooves, wherein the diagonal grooves are arranged through the air holes 34a, and the horizontal and vertical grooves are arranged along the horizontal and vertical directions, so that the diagonal grooves are in communication with each other, thereby ensuring that the fluid entering through the gas path can be quickly dispersed, and the fluid contacts the back surface of the substrate through the air holes 34a and the micro-holes 33a.

[0096] In the present application, the square retaining ring 40 is a rectangular ring structure, as shown in the figure. Figure 4 ​​​​As shown, the bottom surface of the square retaining ring 40 is provided with grooves 41; the grooves 41 are multiple in number and are arranged at intervals between adjacent grooves 41, and the grooves 41 are perpendicular to the side surface of the square retaining ring 40, so that the polishing liquid enters the interior of the square carrier head 100 via the grooves 41 under the square retaining ring 40, and at the same time, the used polishing liquid (polishing waste liquid) is discharged from the square carrier head 100 via the grooves 41.

[0097] Further, the adjusting member 70 is provided on the bottom surface with auxiliary grooves 72, as shown in Figure 6 and 7 which correspond to the positions of the grooves 41, so that the polishing liquid or the polishing waste liquid can enter or be discharged from the square carrier head 100 via the grooves 41 and the auxiliary grooves 72, to prevent the adjusting member 70 from interfering with the supply of the polishing liquid.

[0098] In the present application, the square retaining ring 40 is provided with flushing holes 42, as shown in Figure 3 and Figure 12 which are arranged through in the horizontal direction, and the flushing liquid can enter the interior of the square carrier head 100 via the flushing holes 42 to flush the particulate matter adhering to the outer surface of the loading assembly 30, to prevent the particulate matter from crystallizing and falling to cause scratches.

[0099] Further, the flushing holes 42 are waist-shaped holes, which correspond to the sealing plate 32 of the loading assembly 30, as shown in Figure 12 to timely remove the polishing particulate matter and waste liquid adhering to the outer peripheral side of the loading assembly 30, and prevent crystallization from occurring on the outer peripheral side of the loading assembly 30 to cause scratches on the substrate.

[0100] Especially, the area where the sealing plate 32 is connected to the loading film 33, the size of the loading film 33 is larger than that of the sealing plate 32, and the two form a stepped structure; due to the difference in manufacturing materials, the polishing contaminants can generate tiny vortexes or flow stagnation zones at the corners of the stepped structure. During the polishing process, the loading assembly 30 rotates at high speed around the axis, and the flow rate of these tiny vortexes and stagnation zones is much lower than that of other areas, and after the fluid carrying the polishing contaminants enters these areas, the contaminant particles or molecules have a longer residence time to interact with the surface. The contaminant particles are difficult to be carried away by the high-speed main flow in time, and thus continuously enrich at this place. When the concentration exceeds the solubility limit, crystallization begins.

[0101] To solve the above problems, the flushing hole 42 of the present application is arranged towards the contact between the sealing plate 32 and the loading film 33, to clean the polishing contaminants in this area in a targeted manner, prevent the formation of tiny vortexes and stagnation zones at the corners of the stepped structure, and prevent crystallization from occurring in this area to cause scratches on the substrate.

[0102] In some embodiments, the number of the washing holes 42 is multiple, which are arranged along the outline of the square holding ring 40 to ensure the distribution of the washing liquid is relatively uniform, thereby achieving good washing effect.

[0103] In some embodiments, the washing holes 42 are arranged at the corners of the square holding ring 40 to spray the cleaning liquid towards the corners of the sealing plate 32 and the loading film 33 to prevent the enrichment of particulate matter. Since the adjusting member 70 is arranged at the corner of the square carrier head 100, it blocks the flow direction of the cleaning liquid, therefore, a through hole 73 is arranged at the corresponding position of the adjusting member 70, as shown, so that the sprayed cleaning liquid reaches the corners of the sealing plate 32 and the loading film 33 through the washing hole 42 and the through hole 73 of the corner to prevent the pollutants from remaining at the corners to form crystals. Figure 13

[0104] In some embodiments, the shape of the washing hole 42 is consistent with the shape of the through hole 73, but the size of the washing hole 42 is larger than the size of the through hole 73, so that the cleaning liquid sprayed through the washing hole 42 is sprayed on the outer wall of the adjusting member 70 to clean the pollutants between the adjusting member 70 and the square holding ring 40 by splashing of the liquid, thereby preventing the enrichment of particulate matter in the gap between the two to form crystals.

[0105] In addition, the present application also provides a chemical mechanical polishing system 1000, a schematic diagram of which is shown in Figure 14 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 carrier head 100 shown.

[0106] The polishing pad 300 is arranged on the upper surface of the polishing disc 200 and rotates along the axis Ax together with the polishing disc 200; the horizontally movable square carrier head 100 is arranged above the polishing pad 300, and the lower surface of the square carrier head 100 is loaded with a substrate to be polished; the dressing device 400 includes a dressing arm and a dressing head, which are arranged on one side of the polishing disc 200, and the dressing arm drives the rotating dressing head to swing to dress the surface of the polishing pad 300; the liquid supply device 500 is arranged on the upper side of the polishing pad 300 to spread the polishing liquid on the surface of the polishing pad 300.

[0107] During the polishing operation, the square carrier head 100 presses the surface to be polished of the substrate against the surface of the polishing pad 300, and the square carrier head 100 rotates and reciprocates along the radial direction of the polishing disc 200, so that the surface of the substrate in contact with the polishing pad 300 is gradually polished; at the same time, the polishing disc 200 rotates, and the liquid supply device 500 sprays the polishing liquid on the surface of the polishing pad 300. Under the chemical action of the polishing liquid, the substrate is rubbed with the polishing pad 300 through the relative movement of the square carrier head 100 and the polishing disc 200 to perform polishing.

[0108] ​During chemical mechanical polishing, the dressing device 400 is used to dress and activate the surface topography of the polishing pad 300. Using the dressing device 400 can remove impurity particles remaining on the surface of the polishing pad, such as abrasive particles in the polishing liquid and waste material falling off from the surface of the substrate, and can also flatten the surface deformation of the polishing pad 300 caused by grinding, ensuring the consistency of the surface topography of the polishing pad 300 during polishing, and thus keeping the polishing removal rate stable.

[0109] In this embodiment, the square carrier head 100 is provided with an adjusting member 70, and the floating assembly 80 connected thereto drives the adjusting member 70 to move in the vertical direction through the inner pressure ring 82 to adjust the rebound degree of the polishing pad acting on the outer side area of the corner of the substrate, thereby changing the stress condition of the corner of the substrate and regulating the polishing removal rate of the corner of the substrate.

[0110] Meanwhile, the adjusting member 70 has an L-shaped structure, and the inner side surfaces thereof are arc surfaces and / or inclined surfaces, so that the intersection line of the two inner side surfaces is away from the corner of the substrate to be polished. In this way, the corner of the substrate can be prevented from being broken by colliding with the intersection line of the inner side surfaces of the adjusting member 70.

[0111] Those skilled in the art can appreciate that the units and method steps of the examples described in combination with the embodiments disclosed herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. A person 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 the present application.

[0112] The above embodiments are only used to illustrate the present application, and not to limit the present application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and all equivalent technical solutions belong to the scope of the present application. The patent protection scope of the present 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 disposed below the square base and located 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 arranged above the adjusting component to push the adjusting component up and down. The bottom surface of the adjusting component abuts against the outer area of ​​the four corners of the substrate and causes the polishing pad to deform, thereby changing the load on the corners of the substrate and adjusting the material removal rate at the corners of the substrate. 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; The floating component includes a rolling membrane connected above the fixed ring. The pressurized rolling membrane drives the fixed ring to move vertically. The rolling membrane is equipped with a U-shaped limiting frame inside to limit the expansion and contraction range of the rolling membrane. 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, and the upper connecting rib is located at the top of the rolling ribs. A horizontal lower connecting rib is provided between the rolling ribs, and a protrusion is provided at its bottom. The top surface of the fixing ring is provided with an installation groove, and the protrusion is engaged in the installation groove.

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 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.

8. The square bearing head according to claim 1, 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.

9. 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.

10. 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.

11. 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.

12. The square bearing head according to claim 11, 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.

13. 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.

14. The square bearing head according to claim 11, 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.

15. The square bearing head according to claim 14, characterized in that, The number of flushing holes is multiple, and they are spaced apart along the outline of the square retaining ring.

16. 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 15. 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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