A polishing guard, chemical mechanical polishing system, and polishing method

Abstract

The application discloses a polishing protection device, a chemical mechanical polishing system and a polishing method, and the polishing protection device comprises a ring-shaped baffle ring arranged at the outer circumferential side of a polishing disc, a lifting assembly with a fixed end connected to a base of a polishing system and a moving end connected to the baffle ring to drive the baffle ring to move vertically, and the lifting assembly is provided with a protective sleeve to prevent polishing waste liquid from entering the inside of the lifting assembly.

Description

Technical Field

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

[0002] The integrated circuit industry is the core of the information technology industry, playing a crucial role in promoting the digital and intelligent transformation and upgrading of the manufacturing industry. Chips are the carriers of integrated circuits, and chip manufacturing involves processes such as integrated circuit design, wafer fabrication, wafer processing, electrical measurement, dicing, packaging, and testing. Among these, chemical mechanical polishing (CMP) is one of the five core processes in wafer fabrication.

[0003] 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, with the side of the wafer containing the deposited layer resting against the upper surface of a polishing pad. The support head rotates in the same direction as the polishing pad under the actuation of a drive assembly, applying a downward load to the wafer. 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.

[0004] During the polishing process, the polishing disc rotates at a certain speed, and the polishing waste liquid and cleaning water on the surface of the polishing pad are thrown outward under the action of centrifugal force. In order to control the impact of polishing waste liquid on the polishing unit, an annular retaining ring is usually set on the outer periphery of the polishing disc. The retaining ring is equipped with a lifting mechanism, which drives the retaining ring to move up and down to cooperate with the interaction between the bearing head and the loading cup, preventing the polishing waste liquid from being thrown out without restraint.

[0005] In existing technologies, lifting mechanisms typically lack waterproofing capabilities. Polishing waste liquid can enter the interior of the lifting mechanism and flow down the lifting mechanism to the lower rack of the CMP system, causing water to enter the corresponding area of ​​the lower rack components and thus affecting the safety of the CMP system operation. Summary of the Invention

[0006] In view of this, embodiments of this application provide a polishing protection device, a chemical mechanical polishing system, and a polishing method to at least partially solve the above-mentioned problems.

[0007] According to a first aspect of the embodiments of this application, a polishing protection device is provided for protecting a polishing disc in a polishing system, comprising:

[0008] A ring-shaped retaining ring is disposed on the outer periphery of the polishing disk;

[0009] The lifting assembly has its fixed end connected to the base of the polishing system and its movable end connected to the retaining ring, so as to drive the retaining ring to move vertically.

[0010] The lifting assembly is equipped with a protective sleeve to prevent polishing waste liquid from entering the interior of the lifting assembly.

[0011] In some embodiments, the lifting assembly includes a guide member sleeved on the outer periphery of the mobile end, and a protective sleeve disposed on the outer periphery of the guide member.

[0012] In some embodiments, the guide is a cylindrical structure, which includes a guide seat and a guide tube. The guide seat is fixed to the base, and the guide tube is disposed above the guide seat and slidably connected to the outer periphery of the movable end.

[0013] In some embodiments, the protective sleeve includes a first protective sleeve, which is fitted onto the outer periphery of the guide tube, and the first protective sleeve is connected to the mobile end.

[0014] In some embodiments, the protective sleeve includes a second protective sleeve, which is fitted onto the outer periphery of the first protective sleeve and fixed to the base.

[0015] In some embodiments, the protective sleeve includes a third protective sleeve, which is fitted onto the outer periphery of the second protective sleeve and fixed to the movable end.

[0016] In some embodiments, the outer periphery of the guide tube is provided with annular protrusions, and at least one of the protrusions is disposed on the upper part of the guide tube.

[0017] In some embodiments, the outer periphery of the guide tube has a tapered structure, with its upper outer diameter being smaller than its lower outer diameter, so that the gap between the first protective sleeve and the guide tube gradually decreases from top to bottom.

[0018] In some embodiments, when the mobile end moves to the working position with the retaining ring, the protrusion is located on the upper side of the lower end face of the first protective sleeve.

[0019] In some embodiments, the first protective sleeve is a cylindrical structure with an opening at one end and the opening facing downwards.

[0020] In some embodiments, the second protective sleeve is a cylindrical structure with openings at both ends, which is spaced apart on the outside of the first protective sleeve; the second protective sleeve includes a fixing flange, which is disposed above the guide seat.

[0021] In some embodiments, the third protective sleeve is a cylindrical structure with a single-end opening, the opening of which faces downward and is spaced apart on the outside of the second protective sleeve.

[0022] In some embodiments, the guide seat has a disc-shaped structure, and the protective sleeve is disposed above the guide seat.

[0023] In some embodiments, a drain trough is provided above the guide seat to drain liquid falling through the protective sleeve and guide cylinder.

[0024] In some embodiments, when the moving end of the lifting assembly drives the retaining ring to move upward to the working position, the first protective sleeve, the second protective sleeve, and the third protective sleeve overlap in the vertical direction.

[0025] In some embodiments, when the moving end of the lifting assembly drives the retaining ring to move downward to the standby position, there are gaps between the lower end face of the first protective sleeve and the guide seat, between the upper end face of the second protective sleeve and the top wall of the third protective sleeve, and between the lower end face of the third protective sleeve and the fixing flange of the second protective sleeve.

[0026] In some embodiments, the guide tube is a cylindrical structure with at least one sealing groove for installing a sealing ring on its outer periphery. The sealing groove is located on the upper part of the guide tube, and the first protective sleeve is slidably sealed to the guide tube through the sealing ring.

[0027] In some embodiments, the guide seat is a disc-shaped structure with a drainage groove disposed above it to discharge liquid falling through the protective sleeve and guide cylinder.

[0028] In some embodiments, when the moving end of the lifting assembly drives the retaining ring to move upward to the working position, the sealing ring is located in the vertically overlapping section between the guide cylinder and the first protective sleeve.

[0029] According to a second aspect of the embodiments of this application, a chemical mechanical polishing system is provided, which includes a polishing disc, a support head, a liquid supply device, and a trimming device. The support head presses the wafer to be polished against a polishing pad above the polishing disc. The liquid supply device supplies polishing liquid between the polishing pad and the wafer. The trimming device is used to trim the surface of the polishing pad. It also includes the polishing protection device described above to prevent polishing waste liquid from entering the interior of the lifting assembly.

[0030] According to a third aspect of the embodiments of this application, a polishing method is provided, which uses the chemical mechanical polishing system described above to perform polishing, wherein the lifting component of the polishing protective device is equipped with a protective sleeve to prevent polishing waste liquid from entering the interior of the lifting component.

[0031] The beneficial effects of this invention include:

[0032] a. The lifting assembly of the polishing protection device is equipped with a protective sleeve to prevent polishing waste liquid from entering the interior of the lifting assembly. This prevents the polishing waste liquid from seeping down the lifting assembly to the lower frame of the CMP system and causing water to enter the corresponding parts, thereby ensuring the safety and stability of the CMP system operation.

[0033] b. The protective sleeve is a machined component rather than a consumable, so there is no risk of aging or damage, effectively ensuring the protective effect of the lifting components; at the same time, the protective sleeve does not need to be replaced due to aging, reducing the maintenance time of the CMP system;

[0034] c. There are gaps between the lower end face of the first protective sleeve and the guide seat, between the upper end face of the second protective sleeve and the top wall of the third protective sleeve, and between the lower end face of the third protective sleeve and the fixing flange of the second protective sleeve. When the retaining ring returns to the standby position, the protective sleeve will not interfere with adjacent components.

[0035] d. The lifting assembly is equipped with a guide, which includes a guide cylinder. The outer periphery of the guide cylinder is provided with an annular protrusion, which is integrally formed with the guide cylinder. The protrusion extends outward and downward from the outer side wall of the guide cylinder to prevent the liquid adhering to the outer side wall of the guide cylinder from continuing to move upward.

[0036] e. The outer periphery of the guide tube is a conical structure, with the outer diameter of the upper end being smaller than that of the lower end. This makes the first gap formed between the first protective sleeve and the guide tube gradually smaller from top to bottom, thereby increasing the difficulty for the polishing waste liquid to move from bottom to top toward the lifting assembly through the first gap, and thus improving the waterproof effect of the lifting assembly.

[0037] f. A transition section is provided between the guide tube and the guide seat. The outer wall of the transition section is a conical structure. The outer diameter of the transition section gradually increases from top to bottom. This facilitates the rapid entry of fluid into the drain tank and then flows to the waste liquid outlet through the drain tank.

[0038] g. A drain tank is provided above the guide seat. The drain tank is used to discharge the liquid that falls through the protective sleeve and guide cylinder, so that a small amount of liquid that enters the interior through the protective sleeve can be discharged to the outside of the CMP system through the drain tank, so as to prevent the liquid from affecting the safe operation of other components in the CMP system. Attached Figure Description

[0039] 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.

[0040] Figure 1This is a schematic diagram of a polishing protection device provided in an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of a lifting assembly with a protective sleeve provided in an embodiment of the present invention;

[0042] Figure 3 yes Figure 2 A magnified view of a section at point A in the middle;

[0043] Figure 4 This is a schematic diagram of a guide tube provided in an embodiment of the present invention;

[0044] Figure 5 This is a schematic diagram of a mobile terminal moving to a high position with a retaining ring according to an embodiment of the present invention;

[0045] Figure 6 This is a schematic diagram of a lifting assembly with a protective sleeve provided in another embodiment of the present invention;

[0046] Figure 7 yes Figure 6 A schematic diagram of the mobile terminal moving to a high position with the retaining ring in the embodiment;

[0047] Figure 8 This is a schematic diagram of a chemical mechanical polishing system provided in an embodiment of the present invention. Detailed Implementation

[0048] 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.

[0049] 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 and all possible combinations of one or more of the associated listed items.

[0050] 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.

[0051] Figure 1 This is a schematic diagram of a polishing protection device 100 provided in an embodiment of the present invention. The polishing protection device 100 is used for... Figure 8 The protective device 100 for the polishing disc 200 in the illustrated chemical mechanical polishing system 1000 includes a retaining ring 10. The retaining ring 10 is annular and is disposed on the outer periphery of the polishing disc 200 to block the polishing waste liquid centrifugally ejected from the upper side of the polishing disc 200, thereby inhibiting the outward diffusion of the polishing waste liquid and its contamination of other areas.

[0052] Specifically, a polishing pad is arranged on the upper side of the polishing disk. Polishing fluid is supplied between the wafer and the polishing pad. The wafer, pressed against the surface of the polishing pad, undergoes chemical and mechanical polishing under chemical and mechanical action to remove the material on the wafer surface. After polishing, deionized water (DIW) is supplied to the surface of the polishing pad to clean the contaminants remaining on the surface of the polishing pad. These contaminants and deionized water will be thrown off the inner wall of the baffle ring 100 under centrifugal force and guided to the waste liquid discharge port under gravity.

[0053] The polishing protection device 100 also includes a lifting assembly 20, which comprises a fixed end 21 and a movable end 22, such as Figure 2 As shown, the fixed end 21 is connected to the base 1100 of the chemical mechanical polishing system 1000, and the movable end 22 is the output shaft of the lifting assembly 20, which is connected to the retaining ring 10 to drive the retaining ring 10 to move vertically to cooperate with the lifting assembly 20. Figure 8 The carrier head 300 shown is used for loading and unloading discs and controlling the range of polishing waste liquid spillage.

[0054] Specifically, after the load cup of the carrier head 300 loads the wafer, it needs to move towards the polishing pad 200. At this time, the moving end 22 of the lifting assembly 20 drives the retaining ring 10 to move downward to avoid interference between the carrier head and the retaining ring 10. When the carrier head moves above the polishing pad 200 and presses the loaded wafer against the polishing pad to begin polishing, the moving end 22 of the lifting assembly 20 drives the retaining ring 10 to move upward, so that at least a part of the retaining ring 10 is above the polishing pad to prevent polishing waste liquid from splashing outward, thereby controlling the area where polishing waste liquid falls and preventing polishing waste liquid from contaminating other areas of the polishing system. It should be noted that the loading and unloading platform is usually set to the side of the polishing pad 200, and it is set on the moving path of the carrier head 300 so that the carrier head 300 can load wafers from the loading and unloading platform, or unload wafers from the carrier head 300 to the loading and unloading platform.

[0055] Normally, the lifting assembly 20 is not waterproof. Polishing waste liquid will enter the interior of the lifting assembly 20 and flow down the lifting assembly 20 to the lower rack of the CMP system, causing water to enter the corresponding area of ​​the lower rack of the CMP system, thereby affecting the safety of the CMP system operation.

[0056] To solve the above problems, the polishing protection device 100 provided by the present invention further includes a protective sleeve 30. The protective sleeve 30 can improve the waterproofness of the lifting assembly 20, prevent polishing waste liquid from entering the interior of the lifting assembly 20, and especially prevent polishing waste liquid from splashing onto the moving end 22 of the lifting assembly 20, and prevent the waste liquid from flowing into the guide cylinder 23b of the guide member 23 mentioned below.

[0057] Figure 2 This is a schematic diagram of a lifting assembly 20 with a protective sleeve 30 provided in an embodiment of the present invention. In this embodiment, the lifting assembly 20 includes a guide 23, which is sleeved on the outer periphery of the moving end 22.

[0058] The guide member 23 is fixed to the retaining ring 10 via an adapter plate 40, which connects the moving end 22 and the retaining ring 10, thus enabling the moving end 22 to drive the retaining ring 10 to move vertically. It should be noted that... Figure 2 A portion of the retaining ring 10 is shown using a dashed line; it is a ring structure with a certain height along the vertical direction.

[0059] Furthermore, the guide member 23 has a cylindrical structure with a vertical through hole inside. The moving end 22 is slidably connected to the through hole, so that the moving end 22 can move vertically under the constraint of the guide member 23.

[0060] The guide component 23 includes a guide seat 23a and a guide cylinder 23b, such as Figure 4As shown, the guide seat 23a is fixed to the base 1100, and the guide cylinder 23b is disposed above the guide seat 23a, and the two are integrally formed.

[0061] Figure 2 The movable end 22 shown is slidably connected to the through hole of the guide cylinder 23b, thereby driving the retaining ring 10 fixed by the adapter plate 40 to move smoothly in the vertical direction.

[0062] In this invention, the protective sleeve 30 is disposed on the outer periphery of the guide 23 to improve the waterproof performance of the lifting assembly 20, thereby inhibiting polishing waste liquid or other fluids from entering the interior of the lifting assembly 20 and preventing liquid from entering the lower frame of the CMP system through the lifting assembly 20, which would cause water to enter the corresponding parts.

[0063] Furthermore, the protective sleeve 30 includes a first protective sleeve 31, a second protective sleeve 32, and a third protective sleeve 33, which are arranged sequentially from the inside to the outside, based on the guide member 23. Figure 2 As shown.

[0064] Figure 2 In the middle, the mobile terminal 22 and the connected retaining ring 10 are in the low position, i.e. the standby position, so as to cooperate with the carrier head 300 to complete the loading and unloading of the wafer. Figure 3 yes Figure 2 A magnified view of point A in the middle, to more clearly show the positional relationship between adjacent components.

[0065] The first protective sleeve 31 is a cylindrical structure with a single-end opening facing downwards. It is fitted around the outer periphery of the guide tube 23b. The first protective sleeve 31 is connected to the moving end 22, so that the first protective sleeve 31 can move up and down synchronously with the moving end 22 to provide protection for a part of the moving end 22 and the guide tube 23b.

[0066] The second protective sleeve 32 is a cylindrical structure with openings at both ends, and is spaced apart on the outside of the first protective sleeve 31. The second protective sleeve 32 is fitted onto the outer periphery of the first protective sleeve 31, and is fixed to the base 1100. That is, the second protective sleeve 32 is fixed and its main function is to provide protection for the guide cylinder 23b.

[0067] Furthermore, the second protective sleeve 32 includes a fixed flange 32a, which is disposed above the guide seat 23a and is detachably connected to the base 1100. When the moving end 22 moves upward with the first protective sleeve 31 and the retaining ring 10, the lower part of the guide cylinder 23b will inevitably be exposed to the outside, and polishing waste liquid may splash onto the outer periphery of the guide cylinder 23b.

[0068] In order to reduce or suppress the occurrence of the above situation, the configured second protective sleeve 32 can cover the lower area of ​​the guide cylinder 23b to prevent polishing waste liquid and other fluids from splashing onto the moving end 22 of the lifting assembly 20.

[0069] Figure 5 This is a schematic diagram of a mobile terminal 22 moving to a high position with a retaining ring 10 provided in an embodiment of the present invention. At this time, at least a portion of the retaining ring 10 is located on the upper side of the polishing disk 200 to control the polishing waste liquid centrifugally scattered from the surface of the polishing disk.

[0070] The first protective sleeve 31 and the second protective sleeve 32 are spaced apart to avoid interference between components, thereby ensuring the smooth up-and-down movement of the movable end 22.

[0071] Depend on Figure 5 It can be seen that a second gap G2 with an upward opening is formed between the first protective sleeve 31 and the second protective sleeve 32. Figure 3 As shown, if the second gap G2 is not blocked, the polishing waste liquid will enter the interior of the second protective sleeve 32 along the second gap G2, and then adhere to the outer peripheral wall of the guide cylinder 23b. As the moving end 22 moves up and down, the liquid adhering to the outer peripheral wall of the guide cylinder 23b will enter the interior of the first protective sleeve 31 along the first gap G1 between the guide cylinder 23b and the first protective sleeve 31, and the liquid will further flow down the frame along the moving end 22, contaminating the corresponding components of the CMP system.

[0072] To solve the technical problems mentioned above, the polishing protection device of the present invention is also equipped with a third protective sleeve 33. The third protective sleeve 33 is a cylindrical structure with a single-end opening, and its opening is downward and spaced out on the outside of the second protective sleeve 32.

[0073] Specifically, the third protective sleeve 33 is fitted onto the outer periphery of the second protective sleeve 32 to form a third gap G3 between the third protective sleeve 33 and the second protective sleeve 32, such as Figure 3 As shown. The third gap G3 is set downwards, and the liquid splashed onto the third protective sleeve 33 will slide downwards due to gravity and will hardly enter the second gap G2, thereby preventing the polishing waste liquid from moving towards the inner side where the moving end 22 is located.

[0074] Furthermore, the third protective sleeve 33 is connected to the mobile end 22 and is a follower component, which can move with the mobile end 22.

[0075] Figure 2 and Figure 5 The protective sleeve 30 shown also has the following characteristics:

[0076] When the moving end 22 of the lifting assembly 20 moves the retaining ring 10 downward to the standby position, there are gaps between the lower end face of the first protective sleeve 31 and the guide seat 23a, between the upper end face of the second protective sleeve 32 and the top wall of the third protective sleeve 33, and between the lower end face of the third protective sleeve 33 and the fixing flange 32a of the second protective sleeve 32. When the retaining ring 10 returns to the standby position, the protective sleeve 30 will not interfere with adjacent components.

[0077] At the same time, when the moving end 22 of the lifting assembly 20 drives the retaining ring 10 to move upward to the working position, the first protective sleeve 31, the second protective sleeve 32 and the third protective sleeve 33 overlap in the vertical direction and combine with each other to form a tight waterproof system, thereby inhibiting the movement of polishing waste liquid toward the interior of the lifting assembly 20.

[0078] It should be noted that consumables such as corrugated pipes can be used instead of the protective sleeve 30, but these consumables are at risk of aging and damage. Taking a corrugated pipe as an example, if it is directly fitted onto the outside of the lifting assembly 20 and fixed to the moving end 22, the corrugated pipe will repeatedly extend and retract. If the number of extensions and retractions exceeds its service life, the corrugated pipe will break and fail to provide waterproofing. This waterproofing failure is difficult to detect and can easily lead to water leakage from the CMP system's rack, affecting the safety of the CMP system.

[0079] Compared to technical solutions that use consumables such as bellows alone, the protective sleeve 30 provided by this invention is a machined component, which does not have the risk of aging and damage, effectively ensuring the protective effect of the lifting component 20; at the same time, there is no need to replace the machined component regularly, which helps to reduce the workload of CMP system maintenance.

[0080] Figure 4 This is a schematic diagram of a guide cylinder 23b provided in an embodiment of the present invention. In this embodiment, an annular protrusion 23b-1 is disposed on the outer periphery of the guide cylinder 23b, and the protrusion 23b-1 is integrally formed with the guide cylinder 23b.

[0081] Furthermore, the protrusion 23b-1 extends outward and downward from the outer wall of the guide cylinder 23b to prevent liquid adhering to the outer wall of the guide cylinder 23b from continuing to move upward. In some embodiments, the angle between the protrusion 23b-1 and the central axis of the guide cylinder 23b is 15-85°.

[0082] The lateral dimension of the protrusion 23b-1 is related to the first gap G1, and it is necessary to ensure that the protrusion 23b-1 does not interfere with the inner wall of the first protective sleeve 31, so that the guide cylinder 23b can move smoothly in the first protective sleeve 31. In some embodiments, the lateral dimension of the protrusion 23b-1 is 2-8mm.

[0083] The number of protrusions 23b-1 is at least one, in order to prevent the liquid from moving upward. Figure 4 In the embodiment shown, there is a pair of protrusions 23b-1, both of which are disposed on the outer peripheral wall of the guide cylinder 23b.

[0084] Furthermore, the protrusion 23b-1 is provided on the upper part of the guide cylinder 23b to facilitate the cooperation of the first protective sleeve 31. When the moving end 22 moves up to the working position with the retaining ring 10, the protrusion 23b-1 is always located on the upper side of the lower end face of the first protective sleeve 31 to prevent the guide cylinder 23b and the first protective sleeve 31 from completely separating in the vertical direction without overlapping.

[0085] If the guide tube 23b and the first protective sleeve 31 do not overlap in the vertical direction, the first gap G1 has been damaged. A very small amount of polishing waste liquid may pass through the third gap G3 and the second gap G2 in sequence to move to the moving end 22, which is not conducive to ensuring the waterproofness of the lifting assembly 20.

[0086] Figure 4 In the illustrated embodiment, there is a pair of protrusions 23b-1, which are arranged vertically at intervals on the upper part of the guide cylinder 23b. Typically, an annular protrusion 23b-1 is provided at the top of the guide cylinder 23b. This arrangement helps to control the vertical dimension of the guide cylinder 23b so that the guide cylinder 23b can cooperate with the first protective sleeve 31 to form a first gap G1.

[0087] In this invention, the outer periphery of the guide cylinder 23b has a tapered structure, with its upper outer diameter being smaller than its lower outer diameter, resulting in a first gap G1 formed between the first protective sleeve 31 and the guide cylinder 23b. Figure 3 (As shown) the gap gradually decreases from top to bottom, which increases the difficulty for the polishing waste liquid to move from bottom to top toward the lifting assembly 20 through the first gap G1, thereby improving the waterproof effect of the lifting assembly 20.

[0088] Figure 2 In the embodiment shown, the guide seat 23a has a disc-shaped structure, and the protective sleeve 30 is disposed above the guide seat 23a.

[0089] Furthermore, a drain trough 23a-1 is disposed above the guide seat 23a. The drain trough 23a-1 is used to discharge liquid falling through the protective sleeve 30 and the guide cylinder 23a, so that a very small amount of liquid entering the interior through the protective sleeve 30 is discharged outside the CMP system via the drain trough 23a-1, preventing the liquid from affecting the safe operation of other components in the CMP system. It should be noted that the drain trough 23a-1 is horizontally open on the guide seat 23a, such as... Figure 1 As shown, this allows the liquid to be quickly discharged to the base 1100 with a certain slope, thereby guiding the liquid to the waste liquid outlet and preventing the liquid from accumulating at the guide seat 23a, which would cause the liquid level to rise and backflow into the guide cylinder 23b.

[0090] See Figure 2 and Figure 5 A small amount of liquid enters between the second protective sleeve 32 and the guide cylinder 23b, flows downward under the action of gravity, and finally enters the drain tank 23a-1 through the gap between the inner wall of the fixed flange 32a and the outer wall of the guide cylinder 23b.

[0091] Because the guide tube 23b has a conical structure that is smaller at the top and larger at the bottom, the gap between the second protective sleeve 32 and the guide tube 23b gradually decreases from top to bottom. Therefore, a small amount of liquid that enters the space between the second protective sleeve 32 and the guide tube 23b can quickly enter the drain tank 23a-1.

[0092] at the same time, Figure 4 In the guide member 23 shown, a transition section 23c is disposed between the guide cylinder 23b and the guide seat 23a. The outer wall of the transition section 23c has a tapered structure, and the outer diameter of the transition section 23c gradually increases from top to bottom. The gap between the transition section 23c and the inner wall of the fixed flange 32a gradually decreases from top to bottom, which also facilitates the rapid flow of fluid to the drain tank 23a-1.

[0093] Figure 6 This is a schematic diagram of a lifting assembly 20 equipped with a protective sleeve 30 according to another embodiment of the present invention. This embodiment is similar to... Figure 2 The technical solutions shown have similarities; the differences between the two technical solutions will be highlighted below.

[0094] Furthermore, the number of protective sleeves 30 is one, that is, the first protective sleeve 31 is disposed on the outer periphery of the guide tube 23b of the guide member 23.

[0095] Meanwhile, the guide cylinder 23b has a cylindrical structure and at least one sealing groove is provided on its outer circumference for installing the sealing ring 24, so that the first protective sleeve 31 is slidably and sealed to the guide cylinder 23b through the sealing ring 24.

[0096] In this embodiment, there are two mounting slots, which are located on the upper part of the guide cylinder 23b. The mounting slots are spaced apart along the vertical direction of the guide cylinder 23b to install the corresponding sealing rings 24, thereby achieving a sliding sealing connection between the first protective sleeve 31 and the guide cylinder 23b.

[0097] It should be noted that when the moving end 22 of the lifting assembly 20 drives the retaining ring 10 to move upward to the working position, such as Figure 7 As shown, the sealing ring 24 is located in the vertically overlapping section between the guide tube 23b and the first protective sleeve 31 to prevent the guide tube 23b and the first protective sleeve 31 from detaching from each other and causing waterproofing failure.

[0098] Furthermore, the guide seat 23a of the guide member 23 has a disc-shaped structure, and a drain trough 23b is arranged above it to drain the liquid falling through the protective sleeve 30 and the guide cylinder 23b. Figure 6 The function of the middle drain tank 23b and Figure 2 The same principles apply to the embodiments, so they will not be repeated here.

[0099] It should be noted that in this invention, the protective sleeve 30 is made of a corrosion-resistant material, such as polyoxymethylene (POM). At the same time, the surface of the material used to make the protective sleeve 30 has a certain degree of hydrophobicity, especially the outermost third protective sleeve 33, thereby preventing liquid from adhering to the surface of the protective sleeve 30 and crystallizing.

[0100] In some embodiments, the first protective sleeve 31 and the third protective sleeve 33 are made of a material with a certain strength, such as stainless steel, while the second protective sleeve 32 is made of plastic, such as POM. This arrangement ensures that the materials of adjacent protective sleeves 30 are different, so as to avoid protective sleeves 30 made of the same material from sticking together and affecting the smoothness of component movement.

[0101] In addition, the present invention also provides a chemical mechanical polishing system 1000, the schematic diagram of which is shown below. Figure 8 As shown. The chemical mechanical polishing system 1000 includes a polishing disc 200, a bearing head 300, a liquid supply device 400, and a dressing device 500, and also includes... Figure 1 The polishing protection device 100 shown is disposed on the outside of the polishing disc 200 to control the polishing waste liquid and / or cleaning water ejected by centrifugation.

[0102] Specifically, a polishing pad is disposed on the upper surface of the polishing disk 200 and rotates along the axis together with the polishing disk 200; a horizontally movable support head 300 is disposed above the polishing pad, and the wafer to be polished is loaded on its lower surface; a dressing device 500 includes a dressing arm and a dressing head, which is disposed on one side of the polishing disk 200, and the dressing arm drives the rotating dressing head to swing to dress the surface of the polishing pad; a liquid supply device 400 is disposed on the upper side of the polishing pad to distribute the polishing liquid on the surface of the polishing pad.

[0103] Polishing protection device 100 is disposed on the outer periphery of polishing disc 200, and the lifting component 20 of polishing protection device 100 ( Figure 1 (As shown) It can drive the retaining ring 10 to move in the vertical direction; the lifting assembly 20 is equipped with a protective sleeve 30, which can prevent polishing waste liquid from entering the interior of the lifting assembly 20.

[0104] It should be noted that the polishing waste liquid entering the interior of the lifting assembly 20 refers to the polishing liquid adhering to the inner wall of the moving end 22, and then flowing along the moving end 22 to the interior of the guide cylinder 23b, and then flowing to the fixed end 21 and its interior. This polishing waste liquid will flow along the lifting assembly 20 to the lower rack of the CMP system, causing water to enter the components in the corresponding area of ​​the lower rack.

[0105] Furthermore, the present invention also provides a polishing method, which uses Figure 8 The illustrated chemical mechanical polishing system 1000 is used to perform chemical mechanical polishing. The lifting assembly 20 of the polishing protection device 100 is equipped with a protective sleeve 30 to prevent polishing waste liquid from entering the interior of the lifting assembly 20, thereby ensuring the safety of the chemical mechanical polishing system operation.

[0106] 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.

[0107] 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 polishing protection device for protecting the polishing disc in a polishing system, characterized in that, include: A ring-shaped retaining ring is disposed on the outer periphery of the polishing disc; The lifting assembly has its fixed end connected to the base of the polishing system and its moving end connected to the retaining ring, so as to drive the retaining ring to move vertically. The lifting assembly includes a protective sleeve and a guide. The protective sleeve is disposed on the outer periphery of the guide, and the guide is sleeved on the outer periphery of the moving end to prevent polishing waste liquid from entering the interior of the lifting assembly. The guide is a cylindrical structure, which includes a guide seat fixed to the base and a guide tube. The guide tube is disposed above the guide seat and slidably connected to the outer periphery of the moving end. The protective sleeve includes a first protective sleeve, which is fitted onto the outer periphery of the guide tube and connected to the moving end; the protective sleeve includes a second protective sleeve, which is fitted onto the outer periphery of the first protective sleeve and fixed to the base; the protective sleeve includes a third protective sleeve, which is fitted onto the outer periphery of the second protective sleeve and fixed to the moving end. The outer periphery of the guide tube is provided with an annular protrusion that extends outward and downward from the outer wall of the guide tube, with the angle between the extension direction and the vertical direction being 15°-85°. There is at least one protrusion, which is located on the upper part of the guide tube. The outer periphery of the guide tube has a tapered structure, with the outer diameter of the upper end being smaller than that of the lower end, so that the gap between the first protective sleeve and the guide tube gradually decreases from top to bottom. The guide seat has a disc-shaped structure, and the protective sleeve is disposed above the guide seat; a drainage groove is provided above the guide seat to discharge the liquid falling through the protective sleeve and the guide cylinder.

2. The polishing protection device according to claim 1, characterized in that, When the mobile end moves to the working position with the retaining ring, the protrusion is located on the upper side of the lower end face of the first protective sleeve.

3. The polishing protection device according to claim 1, characterized in that, The first protective sleeve is a cylindrical structure with an opening at one end and the opening is oriented downwards.

4. The polishing protection device according to claim 1, characterized in that, The second protective sleeve is a cylindrical structure with openings at both ends, and is spaced apart on the outside of the first protective sleeve; the second protective sleeve includes a fixing flange, which is disposed above the guide seat.

5. The polishing protection device according to claim 1, characterized in that, The third protective sleeve is a cylindrical structure with an opening at one end, with its opening facing downwards and spaced apart on the outside of the second protective sleeve.

6. The polishing protection device according to claim 5, characterized in that, When the moving end of the lifting component drives the retaining ring to move upward to the working position, the first protective sleeve, the second protective sleeve and the third protective sleeve overlap in the vertical direction.

7. The polishing protection device according to claim 5, characterized in that, When the moving end of the lifting assembly drives the retaining ring to move downward to the standby position, there are gaps between the lower end face of the first protective sleeve and the guide seat, between the upper end face of the second protective sleeve and the top wall of the third protective sleeve, and between the lower end face of the third protective sleeve and the fixing flange of the second protective sleeve.

8. The polishing protection device according to claim 1, characterized in that, The guide tube has a cylindrical structure, and at least one sealing groove for installing a sealing ring is provided on its outer periphery. The sealing groove is located on the upper part of the guide tube, and the first protective sleeve is slidably sealed to the guide tube through the sealing ring.

9. The polishing protection device according to claim 8, characterized in that, When the moving end of the lifting component drives the retaining ring to move upward to the working position, the sealing ring is located in the vertical overlap section between the guide cylinder and the first protective sleeve.

10. A chemical mechanical polishing system, characterized in that, The device includes a polishing pad, a support head, a liquid supply device, and a trimming device. The support head presses the wafer to be polished against the polishing pad above the polishing pad. The liquid supply device supplies polishing liquid between the polishing pad and the wafer. The trimming device is used to trim the surface of the polishing pad. The device also includes a polishing protection device as described in any one of claims 1 to 9 to prevent polishing waste liquid from entering the interior of the lifting assembly.

11. A polishing method, characterized in that, Polishing is performed using the chemical mechanical polishing system of claim 10, wherein the lifting assembly of the polishing protection device is equipped with a protective sleeve to prevent polishing waste liquid from entering the interior of the lifting assembly.

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