Carrier heads and chemical mechanical polishing equipment for wafer processing

Abstract

The present application provides a carrier head and chemical mechanical polishing equipment for wafer processing. The carrier head comprises: a carrier head body; a retaining ring disposed on the side of the carrier head body facing the wafer, the retaining ring confining the wafer therein; and an anti-slip sheet mechanism at least partially disposed within the retaining ring. The anti-slip sheet mechanism is configured to be axially retractable, retracting into the retaining ring when the retaining ring abuts against the polishing unit and extending from the retaining ring when the retaining ring and the polishing unit are axially separated. The anti-slip sheet mechanism is made of a corrosion-resistant material. According to the technical solution of the present application, wafer slippage is effectively prevented, the risk of wafer breakage is reduced, and the effectiveness of the anti-slip sheet mechanism is ensured.

Description

Technical Field

[0001] This application relates to the field of chemical mechanical polishing technology, specifically to a carrier head for wafer processing and a chemical mechanical polishing device. Background Technology

[0002] Chemical mechanical polishing (CMP) is an ultra-precision surface finishing technique that achieves global planarization. In CMP, the wafer is typically held in place by the bottom surface of a support head (also called a polishing head), with a retaining ring at the bottom of the support head radially defining the wafer. The side of the wafer to be polished is pressed against the upper surface of a polishing pad. The support head rotates relative to the polishing pad under the actuation of a drive assembly, applying a downward load to the wafer. Simultaneously, polishing fluid is supplied to the upper surface of the polishing pad and distributed between the wafer and the pad, allowing the wafer to undergo chemical and mechanical polishing through a combination of chemical and mechanical processes. However, sometimes the wafer slips off the support head, leading to wafer damage. Summary of the Invention

[0003] This application provides a carrier head for wafer processing and a chemical mechanical polishing device to solve or alleviate at least some of the problems mentioned above.

[0004] According to one aspect of this application, a carrier head for wafer processing is provided, the carrier head comprising: a carrier head body; a retaining ring disposed on a side of the carrier head body facing the wafer, the retaining ring defining the wafer therein; and an anti-slip mechanism at least partially disposed in the retaining ring, the anti-slip mechanism being configured to be axially telescopic to retract into the retaining ring when the retaining ring abuts against a polishing unit, and to extend from the retaining ring when the retaining ring is axially separated from the polishing unit, the anti-slip mechanism being made of a corrosion-resistant material.

[0005] Optionally or alternatively, the anti-slip plate mechanism includes an axially extending anti-slip plate seat and an anti-slip plate body passing through the anti-slip plate seat; the anti-slip plate seat is disposed in the retaining ring, and the anti-slip plate body is configured to be axially movable relative to the anti-slip plate seat and extendable from the retaining ring; the anti-slip plate body includes a ball bearing assembly disposed at one end of it facing the polishing unit, and the anti-slip plate body makes rolling contact with the polishing unit through the ball bearing assembly.

[0006] Optionally or alternatively, the anti-slip pad body includes a ball bearing assembly disposed at one end of it facing the polishing unit, the anti-slip pad body making rolling contact with the polishing unit through the ball bearing assembly.

[0007] Optionally or alternatively, the ball assembly includes a connecting block and balls that are tactilely connected to the connecting block, the balls having a smooth, dense surface that prevents the accumulation of contaminants.

[0008] Optionally or alternatively, the ball is made of a first plastic material, which includes one or more of polyetheretherketone, polyphenylene sulfide, polyimide, polyethylene terephthalate, and polytetrafluoroethylene.

[0009] Optionally or alternatively, the connecting block is configured with a hemispherical rolling cavity opening toward the polishing unit, in which the ball is partially housed; the ball assembly further includes one or more auxiliary balls disposed between the inner wall of the rolling cavity and the ball, the diameter of the auxiliary balls being equal to the difference between the inner radius of the rolling cavity and the outer radius of the ball, and the balls having a smooth, dense surface to prevent contaminant accumulation.

[0010] Optionally or alternatively, the rolling cavity is configured with a retaining ring extending radially inward from its periphery, through which the ball is partially received in the rolling cavity, the inner diameter of the retaining ring being adapted to the outer diameter of the ball.

[0011] Optionally or alternatively, the anti-slip pad body is elastically abutted against the bearing head body via an elastic member, the anti-slip pad body compresses the elastic member to retract into the retaining ring, and the anti-slip pad body extends out of the retaining ring via the extension of the elastic member.

[0012] Optionally or alternatively, the elastic element is a damper.

[0013] Optionally or alternatively, the elastic element is a spring, which is made of a second plastic material, such as polyamide, polyetheretherketone, or polytetrafluoroethylene.

[0014] Optionally or alternatively, the anti-slip pad body includes an axially extending rod, the rod comprising a first rod segment, a second rod segment, and a third rod segment sequentially away from the bearing head body; the outer diameter of the second rod segment is larger than the outer diameters of the first rod segment and the third rod segment, respectively; the anti-slip pad body is axially limited relative to the anti-slip pad seat by locking the second rod segment; a spring surrounds the outside of the first rod segment, with one end of the spring abutting against the second rod segment and the other end abutting against the bearing head body.

[0015] Optionally or alternatively, the rod is made of polyetheretherketone or polyphenylene sulfide.

[0016] Optionally or alternatively, the bearing head includes a plurality of the anti-slip plate mechanisms distributed circumferentially along the retaining ring.

[0017] Optionally or alternatively, the anti-slip plate mechanism is biased radially inward toward the retaining ring in the radial direction.

[0018] Optionally or alternatively, the anti-slip plate mechanism is configured such that the radial inner side of the retaining ring is within 1 / 5 to 1 / 3 of the radial width of the retaining ring.

[0019] According to another aspect of this application, a chemical mechanical polishing apparatus is provided, the chemical mechanical polishing apparatus including the carrier head described in the foregoing aspect.

[0020] According to the wafer processing support head and chemical mechanical polishing (CMP) equipment of this application, by incorporating an axially extendable anti-slip mechanism at the retaining ring, the anti-slip mechanism can extend from the retaining ring to block the wafer when the retaining ring separates axially from the polishing unit, causing the wafer to tend to slide radially out. This avoids the risk of wafer slippage, reduces wafer breakage, and allows the retaining ring pressure to have a lower pressure limit to prevent wafer slippage. This expands the adjustment range of the retaining ring pressure, improves the polishing adjustment range, operational flexibility, and accuracy of the CMP equipment, thereby enhancing the effectiveness and precision of wafer processing. Furthermore, the anti-slip mechanism is made of corrosion-resistant material, reducing the corrosion of the anti-slip mechanism by the polishing fluid, ensuring its effectiveness, extending its service life, and reducing pollution of the polishing environment caused by corrosion debris from the anti-slip mechanism, thus ensuring the efficient execution of the CMP process. Attached Figure Description

[0021] 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.

[0022] Figure 1 This is a schematic diagram of a chemical mechanical polishing apparatus according to one embodiment of this application;

[0023] Figure 2 A cross-sectional view of a chemical mechanical polishing device;

[0024] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0025] Figure 4 This is a cross-sectional view of a bearing head according to one embodiment of this application;

[0026] Figure 5 for Figure 4 Enlarged view of point B in the image;

[0027] Figure 6 for Figure 5 Enlarged view of the ball bearing assembly of the bearing head;

[0028] Figure 7 for Figure 4 A schematic cross-sectional view of the bearing head in axial contact with the polishing unit;

[0029] Figure 8 for Figure 7 Enlarged view of point C in the image;

[0030] Figure 9 for Figure 4 A schematic cross-sectional view of the bearing head in the polishing unit when it is axially separated from the polishing unit;

[0031] Figure 10 for Figure 9 Enlarged view of point D in the image; and

[0032] Figure 11 for Figure 4 A bottom view of the retaining ring of the bearing head in the diagram.

[0033] Reference numerals :

[0034] Chemical mechanical polishing equipment 1000, polishing unit 1100, bearing head 100, polishing pad 200, polishing disc 300, dressing device 400, liquid supply unit 500.

[0035] The components include: bearing head body 110, gas distribution base 111, main base 112, connecting flange 113, bearing plate 114, first cover plate 1151, second cover plate 1152, elastic diaphragm 116, diaphragm 117, pressure ring 118, and assembly hole 1101.

[0036] Retaining ring 120, mounting hole 121, first hole section 1211, second hole section 1212, groove 122.

[0037] Anti-slip plate mechanism 130, anti-slip plate seat 131, first seat section 131a, second seat section 131b, receiving cavity 1311, through hole 1312, anti-slip plate body 132, rod 1321, first rod section 1321a, second rod section 1321b, third rod section 1321c, ball assembly 1322, connecting block 1322a, ball 1322b, auxiliary ball 1322c, rolling cavity 1322d, retaining ring 1322e, elastic element 133.

[0038] Wafer W, axis Ax. Detailed Implementation

[0039] 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.

[0040] In the description of this application, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0041] In addition, in the description of this application, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0042] Figure 1 This is a schematic diagram of a chemical mechanical polishing (CMP) apparatus 1000 according to one embodiment of this application. The CMP apparatus 1000 may include a polishing unit 1100, a support head 100, a dresser 400, and a liquid supply unit 500. Specifically, the polishing unit 1100 may include a polishing disc 300 and a polishing pad 200. The polishing pad 200 is disposed on the upper surface of the polishing disc 300 and rotates with it along the axis Ax. The horizontally movable support head 100 is disposed above the polishing pad 200, and its lower surface receives the wafer W to be polished. The dresser 400 includes a dressing arm and a dressing head, which is disposed on one side of the polishing disc 300. The dressing arm drives the rotating dressing head to swing to dress the surface of the polishing pad 200. The liquid supply unit 500 is disposed above the polishing pad 200 to distribute the polishing liquid onto the surface of the polishing pad 200.

[0043] Figure 2 This is a schematic cross-sectional view of a chemical mechanical polishing device 1000. Figure 3 for Figure 2Enlarged view at point A. For simplicity, only the carrier head 100, polishing unit 1100, and wafer W are shown. Typically, by adjusting the pressure of the retaining ring 120 of the carrier head 100, the polishing pad 200 can be locally deformed, thereby controlling the edge removal rate of the wafer W. Figure 2 and Figure 3 A schematic diagram is shown showing the wafer sliding out of the carrier head 100. During wafer polishing, the pressure of the retaining ring 120 typically needs to be continuously adjusted. In some processes, when the pressure of the retaining ring 120 is low, the retaining ring 120 may partially separate axially from the polishing unit 1100, causing the wafer W to slide out of the carrier head 100 (specifically, from the retaining ring 120). To prevent slippage, the pressure of the retaining ring 120 is increased. At this time, the friction between the retaining ring 120 and the polishing pad 200 increases, which can easily exacerbate the glazing of the polishing pad 200 (i.e., the surface of the polishing pad becomes smooth), making it easier for the wafer W to slide out. In addition, due to the large friction between the retaining ring 120 and the polishing pad 200, and between the wafer W and the polishing pad 200, the carrier head 100 may be slightly deflected, creating a gap between the retaining ring 120 and the polishing unit 1100, thus causing the wafer to slide out of the carrier head.

[0044] Therefore, the pressure control range of the retaining ring is small. If the pressure is too small, there are problems such as (1) the retaining ring and the polishing unit are not in close axial contact, which leads to slippage. If the pressure is too large, there are problems such as (1) the polishing pad is easily glazed, which leads to slippage, and (2) the friction is too large, which leads to the retaining ring being skewed, which causes slippage.

[0045] To solve one or more of the above problems, Figure 4 A cross-sectional view of a carrier head 100 according to one embodiment of this application is shown, which can be used for Figure 1 The chemical mechanical polishing equipment 1000 shown is an example. Figure 4 The bearing head 100 mainly includes a bearing head body 110 and a retaining ring 120. The bearing head body 110 may include a gas distribution substrate 111, a main substrate 112, a connecting flange 113 for connection, a bearing plate 114, a first cover plate 1151, a second cover plate 1152, and an elastic diaphragm 116. The gas distribution substrate 111 is connected to the main substrate 112 through a diaphragm 117, and the elastic diaphragm 116 is connected to the bottom of the bearing plate 114 through a pressure ring 118. The retaining ring 120 is located on the side of the bearing head body 110 facing the wafer W, i.e. Figure 4 The bearing head body 110 is located on the lower side. A retaining ring 120 is disposed around the outer periphery of an elastic membrane 116, which carries the wafer W and presses the wafer W against the polishing pad 200 of the polishing unit 1100. The retaining ring 120 radially confines the wafer W therein and, together with the wafer W, abuts against the polishing pad 200 for wafer polishing. The retaining ring 120 is constructed with an axially through mounting hole 121.

[0046] Figure 5 for Figure 4 The enlarged view at point B shows that, according to one embodiment of this application, the bearing head 100 further includes an anti-slip plate mechanism 130, which is at least partially disposed in the mounting hole 121. Figure 5 As shown, the anti-slip plate mechanism 130 includes: an anti-slip plate seat 131 and an anti-slip plate body 132 extending axially through the anti-slip plate seat 131. The anti-slip plate body 132 can be elastically abutted against the bearing head body 110, for example via an elastic element 133, such as a spring or damper, thereby being axially telescopic to retract into the mounting hole 121 when the retaining ring 120 abuts against the polishing unit 1100 (see...). Figure 7 , Figure 8 Alternatively, when the retaining ring 120 is axially separated from the polishing unit 1100 (i.e., not completely tightly abutting, including partial or complete separation), it may extend axially from the retaining ring 120 to prevent the wafer from sliding out of the retaining ring 120 (see [reference]). Figure 9 , Figure 10 Specifically, the anti-slip body 132 compresses the elastic element 133 to retract into the mounting hole 121 when the retaining ring 120 abuts against the polishing unit 1100, and is pressed by the elastic element 133 (the elastic element 133 extends) to extend out of the retaining ring 120 when the retaining ring 120 and the polishing unit 1100 are axially separated. Thus, the anti-slip body 132 can block the wafer W from sliding out of the gap between the retaining ring 120 and the polishing unit 1100. The anti-slip mechanism 130 can be made of a corrosion-resistant material to reduce the corrosion of the anti-slip mechanism 130 by the polishing fluid.

[0047] According to the technical solution of this application, by providing an axially extendable anti-slip plate mechanism 130 at the retaining ring 120, when the pressure between the retaining ring 120 and the polishing unit 1100 is small and axial separation causes the wafer W to tend to slide out radially, or when the friction between the retaining ring 120 and the polishing unit 1100 is large and the bearing head 100 is tilted, causing the wafer W to tend to slide out radially, the anti-slip plate mechanism 130, specifically the anti-slip plate body 132, can extend from the retaining ring 120 to block the wafer W, thereby avoiding the risk of wafer slippage and reducing wafer breakage. At the same time, this allows the pressure of the retaining ring 120 to have a higher upper pressure limit and a lower lower pressure limit to keep the wafer from slipping out, expanding the adjustment range of the retaining ring 120 pressure, improving the polishing adjustment range, operational flexibility and accuracy of the chemical mechanical polishing equipment 1000, and thus improving the effectiveness and precision of wafer processing. In addition, the anti-slip pad mechanism 130 can be made of corrosion-resistant materials, thereby reducing the corrosion of the anti-slip pad mechanism 130 by the polishing fluid, ensuring the effectiveness of the anti-slip pad mechanism 130, extending its service life, and reducing the pollution of the polishing environment caused by the corrosion and chipping of the anti-slip pad mechanism 130, thus ensuring the efficient operation of the chemical mechanical polishing process.

[0048] like Figure 5 and Figure 6 As shown in the enlarged view, the anti-slip pad body 132 may include an axially extending rod 1321 and a ball bearing assembly 1322 connected to one end of the rod 1321 facing the polishing unit 1100 (i.e., the lower end shown in the figure). The anti-slip pad body 132 makes rolling contact with the polishing unit 1100 through the ball bearing assembly 1322, thereby reducing the friction between the anti-slip pad body 132 and the polishing pad 200, thereby reducing the wear caused by the anti-slip pad body 132 on the polishing pad 200, improving the service life of the anti-slip pad body 132 and the polishing pad 200, and ensuring the wafer polishing efficiency.

[0049] In a specific embodiment, the ball assembly 1322 may include a connecting block 1322a and a ball 1322b. The connecting block 1322a is configured with a hemispherical rolling cavity 1322d that opens toward the polishing unit 1100. The ball 1322b is partially (e.g., half of the ball 1322b) housed in the rolling cavity 1322d and is rollable in all directions relative to the rolling cavity 1322d, thereby forming a universal ball. The ball assembly 1322 may also include one or more auxiliary balls 1322c disposed between the inner wall of the rolling cavity 1322d and the ball 1322b. The diameter of the auxiliary balls 1322c is equal to the difference between the inner radius of the rolling cavity 1322d and the outer radius of the ball 1322b, that is, the auxiliary balls 1322c are tangentially disposed to the rolling cavity 1322d and the ball 1322b, respectively. By setting auxiliary ball 1322c, rolling connection between ball 1322b and rolling cavity 1322d can be achieved, reducing rolling friction between ball 1322b and rolling cavity 1322d, reducing wear between the two, and improving the smoothness of rolling of ball 1322b, thereby improving the smoothness of relative movement between anti-slip plate mechanism 130 and polishing unit 1100.

[0050] According to the ball assembly 1322 of this application, the anti-slip pad body 132 makes rolling contact with the polishing unit 1100, thereby reducing the friction between the anti-slip pad body 132 and the polishing pad 200, thus reducing the wear caused by the anti-slip pad body 132 on the polishing pad 200, improving the service life of the anti-slip pad body 132 and the polishing pad 200, and ensuring wafer polishing efficiency. Furthermore, the ball assembly 1322 transforms at least partially the sliding friction between the retaining ring 120 and the polishing unit 1100 into rolling friction, reducing the contact area between the retaining ring 120 and the polishing pad 200, lowering the friction between them, thereby reducing the wear of the retaining ring 120 on the polishing pad 200, slowing down the glazing effect or glazing speed of the polishing pad 200, and thus reducing the risk of the wafer W slipping out due to glazing of the polishing pad 200.

[0051] In a preferred embodiment, the ball 1322b has a smooth and dense surface to prevent the accumulation of contaminants on its surface, ensuring its cleanliness and surface smoothness. Contaminants include, for example, debris generated during wafer polishing. The ball 1322b can be made of a first plastic material, including one or more of, for example, polyetheretherketone (PEEK), polyphenylene sulfide (PPS), polyimide (PAI), polyethylene terephthalate (PET-P), and polytetrafluoroethylene (PTFE). These plastic materials have good wear resistance and chemical corrosion resistance, which helps reduce wear and chemical corrosion of the ball 1322b, ensuring the surface smoothness and rolling smoothness of the ball, and reducing the pollution of the wafer polishing environment by ball wear or corrosion debris.

[0052] Furthermore, the connecting block 1322a and the rod 1321 may also be made of the same or different plastic material as the balls. The rod 1321 may be made of, for example, polyetheretherketone (PEEK) or polyphenylene sulfide (PPS). The auxiliary balls 1322c may also be made of, for example, a smooth and dense material to have a smooth and dense surface.

[0053] In a further embodiment, the rolling cavity 1322d is configured with a retaining ring 1322e extending radially inward from its periphery. Figure 6 In one embodiment, the retaining ring 1322e is integrally formed on the connecting block 1322a; in other embodiments, it may be formed separately from the connecting block 1322a. The ball 1322b passes through the retaining ring 1322e and is partially accommodated in the rolling cavity 1322d. The inner diameter of the retaining ring 1322e is adapted to the outer diameter of the ball 1322b, for example, allowing a small gap between them to roll relative to each other. Figure 6 The retaining ring 1322e has a certain thickness in its vertical direction, and the middle position of its thickness matches the diameter of the ball 1322b. The radially inward side of the retaining ring 1322e can be a curved annular surface that matches the outer surface of the ball 1322b, thereby restricting the ball 1322b and preventing it from falling out of the rolling cavity 1322d through the retaining ring 1322e. The retaining ring 1322e can confine the auxiliary ball 1322c in the rolling cavity 1322d, preventing the auxiliary ball 1322c from coming out of the rolling cavity 1322d. In addition, the retaining ring 1322e can also block polishing fluid or other contaminants from entering the rolling cavity 1322d to a large extent, ensuring the cleanliness of the rolling cavity 1322d and reducing the possibility of the rolling cavity 1322d failing due to contamination.

[0054] In a preferred embodiment, the end of the connecting block 1322a facing the rod 1321 can be threadedly connected to the rod 1321. Specifically, the end of the connecting block 1322a facing the rod 1321 can be constructed with a threaded hole that is recessed away from the rod 1321, for example... Figure 6 The connecting block 1322a has an upward-opening hole at its upper part. The end of the rod 1321 facing the connecting block 1322a can be constructed with an external thread that matches the threaded hole. The connecting block 1322a and the rod 1321 are threadedly connected via the threaded hole and the external thread.

[0055] See also Figure 5In the illustrated embodiment, the mounting hole 121 of the retaining ring 120 includes a first hole segment 1211 and a second hole segment 1212 sequentially away from the support head body 110. The first hole segment 1211 is configured to receive the anti-slip pad seat 131, and the second hole segment 1212 is configured to allow the anti-slip pad body 132 to pass through. The anti-slip pad seat 131 includes an axially extending receiving cavity 1311 that opens toward the support head body 110, and the receiving cavity 1311 has a through hole 1312 formed at its bottom opposite to the support head body 110. The anti-slip plate body 132 has three rods 1321, including a first rod segment 1321a, a second rod segment 1321b, and a third rod segment 1321c, which are sequentially located away from the bearing head body 110. The outer diameter of the second rod segment 1321b is larger than the outer diameters of the first rod segment 1321a and the third rod segment 1321c, and the outer diameter of the second rod segment 1321b is larger than the inner diameter of the through hole 1312, so that the second rod segment 1321b is confined in the receiving cavity 1311 and does not come out of the receiving cavity 1311. The first rod segment 1321a and the second rod segment 1321b are axially movable and accommodated in the receiving cavity 1311. The third rod segment 1321c is connected to the ball assembly 1322, for example, by threaded connection to the connecting block 1322a of the ball assembly 1322. Figure 5 In the embodiment where the elastic element 133 shown is a spring, the spring surrounds the outside of the first rod segment 1321a, and one end of the spring abuts against the second rod segment 1321b, and the other end abuts against the bearing head body 110, so as to realize the axial extension and retraction of the anti-slip plate body 132.

[0056] In a preferred embodiment, the spring can be made of a second plastic material, such as polyamide (PA, commonly known as nylon), polyetheretherketone (PEEK), or polytetrafluoroethylene (PTFE). Making the spring of a plastic material reduces chemical corrosion, ensures the stability of its elastic properties, and thus guarantees the effectiveness of its elastic action. This allows the anti-slip mechanism 130 to perform its anti-slip operation promptly and effectively, preventing the wafer from slipping out. It should be understood that the first and second plastic materials can be the same or different.

[0057] From the external structure, the anti-slip pad seat 131 may include a first section 131a assembled in the bearing head body 110 and a second section 131b assembled in the mounting hole 121. The outer diameter of the first section 131a may be larger than the outer diameter of the second section 131b, and a chamfered or rounded transition structure may be provided between them to reduce stress concentration and improve structural strength. Correspondingly, the bearing head body 110 (specifically the main base 112) may be constructed with a mounting hole 1101 opening toward the retaining ring 120. The size and position of the mounting hole 1101 match the first section 131a, and the mounting hole 1101 and the first section 131a may be threadedly engaged. The elastic member 133 may abut against the bottom of the mounting hole 1101 toward the bearing head body 110. In a preferred embodiment, the edge of the mounting hole 1101 may also be designed as a transition structure that matches the transition structure between the first section 131a and the second section 131b. It should be understood that, in addition to the anti-slip pad seat 131 being partially disposed in the mounting hole 121 and partially disposed in the assembly hole 1101 as shown in the figure, in an optional embodiment, the anti-slip pad seat 131 can also be entirely disposed in the mounting hole 121. In this case, the bearing head body 110 may not be provided with the assembly hole 1101, and the elastic element 133 directly abuts against the bottom surface of the bearing head body 110.

[0058] Figure 7 for Figure 4 A schematic cross-sectional view of the bearing head 100 in axial contact with the polishing unit 1100; Figure 8 for Figure 7 The enlarged view at point C shows that the retaining ring 120 is axially abutting against the polishing unit 1100, at which point the wafer W is held in the retaining ring 120, and the anti-slip mechanism 130 is retracted in the mounting hole 121 of the retaining ring 120. Figure 9 for Figure 4 A schematic cross-sectional view of the bearing head 100 when it is axially separated from the polishing unit 1100; Figure 10 for Figure 9 The enlarged view at point D shows that the carrier head 100 is slightly tilted, and the retaining ring 120 is slightly separated from the polishing unit 1100 axially. At this time, the wafer W tends to slide radially out of the retaining ring 120. The anti-slip plate mechanism 130 extends axially outward from the mounting hole 121 of the retaining ring 120 under the action of the elastic element 133. The radially inner sidewall of the connecting block 1322a of the ball assembly 130 radially blocks the wafer W. During the subsequent rotation of the carrier head, the wafer W will be driven back into the retaining ring 120, thereby avoiding the wafer from sliding out and the resulting wafer breakage. At the same time, when actively adjusting the pressure of the retaining ring 120, it is also possible to adjust to a smaller pressure without causing the wafer to slide out. Therefore, a large adjustment range of the retaining ring 120 pressure is achieved, improving the flexibility and accuracy of polishing control.

[0059] In a preferred embodiment, the bearing head 100 may include a plurality of anti-slip plate mechanisms 130 distributed circumferentially along the retaining ring 120. Figure 11 for Figure 4 The diagram shows a bottom view of the retaining ring 120 of the bearing head 100, illustrating a plurality of anti-slip pad mechanisms 130 distributed circumferentially along the retaining ring 120. In the illustrated embodiment, the retaining ring 120 has a plurality of grooves 122 recessed from the surface of the retaining ring 120 away from the polishing unit 1100 on the side facing the polishing unit 1100. These grooves 122 penetrate the outer and inner sides of the retaining ring 120 in the radial direction, thereby forming channels for the flow of polishing fluid or debris into or out of the retaining ring 120. The plurality of grooves 122 may be evenly distributed circumferentially along the retaining ring 120, or in an alternative embodiment, one anti-slip pad mechanism 130 may be provided between two adjacent grooves 122, or two or more anti-slip pad mechanisms 130 may be evenly spaced circumferentially between two adjacent grooves 122, i.e., the number of anti-slip pad mechanisms 130 may be an integer multiple of the number of grooves 122.

[0060] In addition, Figure 4 , 5 or Figure 8 In the illustrated embodiment, the anti-slip mechanism 130 can be offset radially inward toward the retaining ring 120, for example, by being positioned within 1 / 5 to 1 / 3 of the radial width of the retaining ring 120 from its radial inward side, thereby enabling faster and more effective wafer blocking. The position of the anti-slip mechanism 130 described herein can be understood as the position of the central axis of the anti-slip mechanism 130 or the position of the vertical axis of the ball 1322b.

[0061] The following is a brief introduction Figure 4 or Figure 5 An exemplary assembly method for the carrier head 100 shown.

[0062] S1: The anti-slip plate assembly mechanism 130 may specifically include:

[0063] S1-1: Insert rod 1321 into anti-slip plate seat 131;

[0064] S1-2: Connect the ball assembly to the rod 1321;

[0065] S1-3: Assemble the elastic element 133 onto the rod 1321;

[0066] S2: Assemble the anti-slip plate mechanism 130 onto the bearing head body 110, specifically onto the mounting hole 1101.

[0067] S3: Assemble the retaining ring 120 onto the bearing head body 110, specifically by fitting the mounting hole 121 of the retaining ring 120 onto the outside of the anti-slip plate mechanism 130, that is: insert the anti-slip plate mechanism 130 into the mounting hole 121.

[0068] It should be understood that the above assembly method is merely exemplary, and the specific assembly operation or the order of each step can be appropriately adjusted when the bearing head 100 has other structural forms.

[0069] 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 carrier head for wafer processing, characterized in that, The bearing head includes: The main body of the bearing head; A retaining ring is disposed on the side of the carrier head body facing the wafer, and the retaining ring confines the wafer therein; by adjusting the pressure of the retaining ring, the polishing pad below the carrier head is locally deformed, thereby controlling the wafer edge removal rate; An anti-slip mechanism, at least partially disposed within the retaining ring, is configured to be axially retractable to retract into the retaining ring when it abuts against the polishing unit, and to extend from the retaining ring when the pressure between the retaining ring and the polishing unit is low and axial separation causes the wafer to tend to slide radially out, or when the friction between the retaining ring and the polishing unit is high and the bearing head is misaligned, causing the wafer to tend to slide radially out, thereby preventing the wafer from sliding out and expanding the pressure adjustment range of the retaining ring; the anti-slip mechanism is made of a corrosion-resistant material; The anti-slip plate mechanism includes an axially extending anti-slip plate seat and an anti-slip plate body passing through the anti-slip plate seat; the anti-slip plate seat is disposed in the retaining ring, and the anti-slip plate body is configured to be axially movable relative to the anti-slip plate seat and extendable from the retaining ring; the anti-slip plate body includes a ball assembly disposed at one end of it facing the polishing unit, and the anti-slip plate body makes rolling contact with the polishing unit through the ball assembly.

2. The bearing head according to claim 1, characterized in that, The ball assembly includes a connecting block and balls that are tactilely connected to the connecting block, the balls having a smooth, dense surface that prevents the accumulation of contaminants.

3. The bearing head according to claim 2, characterized in that, The ball bearing is made of a first plastic material, which includes one or more of polyetheretherketone, polyphenylene sulfide, polyimide, polyethylene terephthalate, and polytetrafluoroethylene.

4. The bearing head according to claim 2, characterized in that, The connecting block is configured with a hemispherical rolling cavity that opens toward the polishing unit, and the ball is partially accommodated in the rolling cavity; the ball assembly also includes one or more auxiliary balls disposed between the inner wall of the rolling cavity and the ball, the diameter of the auxiliary balls being equal to the difference between the inner radius of the rolling cavity and the outer radius of the ball, and the auxiliary balls having a smooth and dense surface.

5. The bearing head according to claim 4, characterized in that, The rolling cavity is configured with a retaining ring extending radially inward from its periphery, through which the ball is partially accommodated in the rolling cavity, and the inner diameter of the retaining ring is adapted to the outer diameter of the ball.

6. The bearing head according to any one of claims 1-5, characterized in that, The anti-slip plate body is elastically abutted against the bearing head body via an elastic member. The anti-slip plate body compresses the elastic member to retract into the retaining ring, and the anti-slip plate body extends out of the retaining ring via the extension of the elastic member.

7. The bearing head according to claim 6, characterized in that, The elastic element is a damper.

8. The bearing head according to claim 6, characterized in that, The elastic element is a spring, which is made of a second plastic material, namely polyamide, polyetheretherketone, or polytetrafluoroethylene.

9. The bearing head according to claim 8, characterized in that, The anti-slip pad body includes an axially extending rod, which includes a first rod segment, a second rod segment, and a third rod segment that are sequentially moved away from the bearing head body. The outer diameter of the second rod segment is larger than the outer diameters of the first rod segment and the third rod segment, respectively. The anti-slip pad body is axially limited relative to the anti-slip pad seat via the second rod segment. The spring surrounds the outside of the first rod segment, with one end of the spring abutting against the second rod segment and the other end abutting against the bearing head body.

10. The bearing head according to claim 9, characterized in that, The rod is made of polyetheretherketone or polyphenylene sulfide.

11. The bearing head according to any one of claims 1-5, characterized in that, The bearing head includes a plurality of anti-slip plate mechanisms distributed circumferentially along the retaining ring.

12. The bearing head according to any one of claims 1-5, characterized in that, The anti-slip plate mechanism is offset radially inward toward the retaining ring in the radial direction.

13. The bearing head according to claim 12, characterized in that, The anti-slip plate mechanism is configured such that the radial inner side of the retaining ring is within 1 / 5 to 1 / 3 of the radial width of the retaining ring.

14. A chemical mechanical polishing apparatus, characterized in that, The chemical mechanical polishing equipment includes a bearing head according to any one of claims 1-13.

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