Polishing protection device, chemical mechanical polishing system and polishing method

Abstract

The invention discloses a polishing protection device, a chemical mechanical polishing system and a polishing method.The polishing protection device comprises a check ring of an annular structure, a polishing disc, a first driving device and a second driving device, and the check ring is arranged on the peripheral side of the polishing disc; the fixed end of the lifting assembly is connected to a base of the polishing system, and the movable end of the lifting assembly is connected to the check ring so as to drive the check ring to move in the vertical direction; the lifting assembly is provided with a protective sleeve so as to prevent polishing waste liquid from entering the lifting assembly.

Description

Technical Field

[0001] The embodiments of the present application relate 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 Art

[0002] The integrated circuit industry is the core of the information technology industry and plays a key role in promoting the transformation and upgrading of the manufacturing industry towards digitalization and intelligence. Chips are the carriers of integrated circuits, and chip manufacturing involves process flows such as integrated circuit design, wafer manufacturing, wafer processing, electrical measurement, cutting packaging and testing. Among them, chemical mechanical polishing is one of the five core processes in the wafer manufacturing process.

[0003] Chemical Mechanical Polishing (CMP) is an ultra-precision surface processing technology for global flattening. Chemical mechanical polishing usually involves sucking the wafer onto the bottom surface of a carrier head, with the side of the wafer with the deposition layer abutting against the upper surface of the polishing pad. The carrier head rotates in the same direction as the polishing pad under the actuation of the drive assembly and applies a downward load to the wafer; the polishing liquid is supplied to the upper surface of the polishing pad and distributed between the wafer and the polishing pad, so that the wafer completes the chemical mechanical polishing of the wafer under the combined action of chemistry and mechanics.

[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 will be thrown outward under the action of centrifugal force. In order to control the impact of the polishing waste liquid on the polishing unit, an annular retaining ring is usually set on the outer peripheral side of the polishing disc. The retaining ring is equipped with a lifting mechanism. The lifting mechanism drives the retaining ring to move up and down to cooperate with the interaction between the carrier head and the loading and unloading platform (load cup) to prevent the unlimited throwing out of the polishing waste liquid.

[0005] In the prior art, the lifting mechanism usually has no waterproof function. The polishing waste liquid will enter the interior of the lifting mechanism and flow along the lifting mechanism to the lower frame of the CMP system, causing water to enter the components in the corresponding area of ​​the lower frame, thereby affecting the safety of the CMP system operation. Summary of the invention

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

[0007] According to a first aspect of an embodiment of the present application, a polishing protection device is provided for protecting a polishing disk in a polishing system, comprising:

[0008] A retaining ring of an annular structure, arranged on the outer peripheral side of the polishing disc;

[0009] A lifting assembly, the fixed end of which is connected to the base of the polishing system, and the movable end of which is connected to the retaining ring to drive the retaining ring to move vertically;

[0010] The lifting component is provided with a protective cover to prevent polishing waste liquid from entering the interior of the lifting component.

[0011] In some embodiments, the lifting assembly includes a guide member, which is sleeved on the outer peripheral side of the moving end, and the protective sleeve is arranged on the outer peripheral side of the guide member.

[0012] In some embodiments, the guide member 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 arranged above the guide seat and slidably connected to the outer peripheral side of the movable end.

[0013] In some embodiments, the protective sleeve includes a first protective sleeve, which is sleeved on the outer circumference of the guide tube, and the first protective sleeve is connected to the movable end.

[0014] In some embodiments, the protective sleeve includes a second protective sleeve, which is sleeved on the outer circumference of the first protective sleeve and fixed to the base.

[0015] In some embodiments, the protective cover includes a third protective cover, which is sleeved on the outer circumference of the second protective cover and fixed to the mobile end.

[0016] In some embodiments, an annular protrusion is disposed on the outer circumference of the guide tube, and the number of the protrusion is at least one and the protrusion is disposed on the upper portion of the guide tube.

[0017] In some embodiments, the outer peripheral side of the guide tube is a conical structure, and the outer diameter of the upper end is smaller than the outer diameter of the lower end, so that the gap formed by the first protective sleeve and the guide tube gradually decreases from top to bottom.

[0018] In some embodiments, when the movable end moves up to the working position with the retaining ring, the protrusion is located on the upper side of the lower end surface 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 is arranged downward.

[0020] In some embodiments, the second protective sleeve is a cylindrical structure with openings at both ends, which is spaced apart outside 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 tubular structure with an opening at one end, the opening of which faces downward and is spaced apart from the outside of the second protective sleeve.

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

[0023] In some embodiments, a drain groove is disposed above the guide seat to discharge the liquid that falls through the protective sleeve and the guide tube.

[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 surface of the first protective cover and the guide seat, between the upper end surface of the second protective cover and the top wall of the third protective cover, and between the lower end surface of the third protective cover and the fixed flange of the second protective cover.

[0026] In some embodiments, the guide tube is a cylindrical structure, and its outer circumference is configured with at least one sealing groove for installing a sealing ring. The sealing groove is arranged on the upper part of the guide tube, and the first protective sleeve is slidingly and sealingly connected to the guide tube through the sealing ring.

[0027] In some embodiments, the guide seat is a disc-shaped structure, and a liquid drain groove is disposed on the top of the disc to drain the liquid that falls through the protective sleeve and the guide tube.

[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 vertical overlapping section between the guide tube and the first protective sleeve.

[0029] According to the second aspect of an embodiment of the present application, a chemical mechanical polishing system is provided, which includes a polishing disk, a carrying head, a liquid supply device and a trimming device, wherein the carrying head presses the wafer to be polished against the polishing pad above the polishing disk, the liquid supply device supplies polishing liquid between the polishing pad and the wafer, and 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 an embodiment of the present application, a polishing method is provided, which uses the chemical mechanical polishing system described above to implement polishing, and the lifting assembly of the polishing protection device is equipped with a protective cover to prevent polishing waste liquid from entering the interior of the lifting assembly.

[0031] The beneficial effects of the present invention include:

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

[0033] b. The protective cover is a processing component rather than a consumable, so it does not have the risk of aging and damage, effectively ensuring the protective effect of the lifting component; at the same time, the protective cover does not have the problem of aging and replacement, which reduces the maintenance operation time of the CMP system;

[0034] c. There are gaps between the lower end surface of the first protective sleeve and the guide seat, between the upper end surface of the second protective sleeve and the top wall of the third protective sleeve, and between the lower end surface 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 provided with a guide member, which includes a guide cylinder, and an annular protrusion is provided on the outer peripheral side of the guide cylinder, and the protrusion is integrally formed with the guide cylinder; the protrusion extends outward and downward from the outer wall of the guide cylinder to prevent the liquid attached to the outer wall of the guide cylinder from continuing to move upward;

[0036] e. The outer peripheral side of the guide tube is a tapered structure, and the outer diameter of the upper end is smaller than the outer diameter of the lower end, so that the first gap formed by the first protective sleeve and the guide tube gradually decreases from top to bottom, thereby increasing the difficulty of the polishing waste liquid moving from bottom to top toward the lifting assembly through the first gap, thereby improving the waterproof effect of the lifting assembly;

[0037] f. A transition section is arranged between the guide cylinder and the guide seat. The outer wall of the transition section is a tapered structure. The outer diameter of the transition section gradually increases from top to bottom, which is conducive to the fluid quickly entering the drainage groove and then flowing to the waste liquid discharge outlet through the drainage groove;

[0038] g. A drainage trough is arranged above the guide seat, and is used to discharge the liquid that falls through the protective sleeve and the guide cylinder, so as to discharge a small amount of liquid that enters the interior through the protective sleeve to the outside of the CMP system through the drainage trough to prevent the liquid from affecting the safe operation of other components in the CMP system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

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

[0041] Figure 2 is a schematic diagram of a lifting assembly equipped with a protective cover provided in one embodiment of the present invention;

[0042] Figure 3 yes Figure 2 A partial enlarged view of the middle A;

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

[0044] Figure 5 It is a schematic diagram of a mobile end provided by an embodiment of the present invention moving to a high position with a retaining ring;

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

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

[0047] Figure 8 Schematic diagram of a chemical mechanical polishing system provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0049] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more 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 the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0051] Figure 1 is a schematic diagram of a polishing protection device 100 provided in one embodiment of the present invention. The polishing protection device 100 is used Figure 8 The protection of the polishing disc 200 in the chemical mechanical polishing system 1000 is shown. Specifically, the polishing protection device 100 includes a retaining ring 10, which is an annular structure and is arranged on the outer peripheral side of the polishing disc 200 to block the polishing waste liquid centrifugally ejected from the upper side of the polishing disc 200, and inhibit the polishing waste liquid from spreading outward and contaminating other areas.

[0052] Specifically, a polishing pad is arranged on the upper side of the polishing disk, and the polishing liquid is supplied between the wafer and the polishing pad. The wafer pressed against the surface of the polishing pad completes chemical mechanical polishing under the action of chemical and mechanical forces to remove the material on the surface of the wafer; after polishing, deionized water (DIW) is supplied toward 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 to the inner wall of the retaining ring 100 under the action of centrifugal force and guided to the waste liquid discharge outlet under the action of gravity.

[0053] The polishing protection device 100 further includes a lifting assembly 20, which includes a fixed end 21 and a movable end 22. 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 in the vertical direction to cooperate with Figure 8 The carrier head 300 shown is used to load and unload wafers, and to control the range of discarding of polishing waste liquid.

[0054] Specifically, after the carrier head 300 loads the wafer from the loading cup, it needs to move toward the direction of the polishing disk 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 to the top of the polishing disk 200, the carrier head presses the loaded wafer against the top of the polishing pad to start polishing, and the moving end 22 of the lifting assembly 20 drives the retaining ring 10 to move upward, so that at least part of the retaining ring 10 is located above the polishing pad to prevent the polishing waste liquid from splashing outward, thereby controlling the falling area of ​​the polishing waste liquid and avoiding the polishing waste liquid from contaminating other areas of the polishing system. It should be noted that the loading cup is usually arranged on the side of the polishing disk 200, and is arranged on the moving path of the carrier head 300, so that the carrier head 300 can load the wafer from the loading cup, or unload the wafer of the carrier head 300 to the loading cup.

[0055] Usually, the lifting assembly 20 has no waterproof function, and the polishing waste liquid will enter the interior of the lifting assembly 20 and flow along the lifting assembly 20 to the lower frame of the CMP system, causing water to enter the components in the corresponding area of ​​the lower frame of the CMP system, thereby affecting the safety of the operation of the CMP system.

[0056] To solve the above problems, the polishing protection device 100 provided by the present invention also includes a protective cover 30, which can improve the waterproofness of the lifting assembly 20, block the polishing waste liquid from entering the interior of the lifting assembly 20, and especially prevent the 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 tube 23b of the guide member 23 mentioned below.

[0057] Figure 2 3 is a schematic diagram of a lifting assembly 20 provided with a protective cover 30 according to an embodiment of the present invention. In this embodiment, the lifting assembly 20 includes a guide member 23 , which is sleeved on the outer peripheral side of the moving end 22 .

[0058] The guide member 23 is fixed to the retaining ring 10 through the adapter plate 40, and the adapter plate 40 is connected between the moving end 22 and the retaining ring 10, so that the moving end 22 can drive the retaining ring 10 to move in the vertical direction. Figure 2 A portion of the retaining ring 10 is shown using dot-dash lines. The retaining ring 10 is an annular structure and has a certain height in the vertical direction.

[0059] Furthermore, the guide member 23 is a cylindrical structure, and a vertical through hole is provided inside the guide member 23 . The movable end 22 is slidably connected in the through hole, so that the movable end 22 can move along the vertical direction under the limitation of the guide member 23 .

[0060] The guide member 23 includes a guide seat 23a and a guide cylinder 23b. Figure 4As shown, the guide seat 23a is fixed to the base 1100, and the guide tube 23b is disposed above the guide seat 23a, and the two are formed in one piece.

[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 the present invention, the protective cover 30 is arranged on the outer peripheral side of the guide member 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 the liquid from entering the lower frame of the CMP system through the lifting assembly 20 and causing water to enter the components in the corresponding area.

[0063] Furthermore, the protective cover 30 includes a first protective cover 31, a second protective cover 32 and a third protective cover 33, which are arranged in sequence from the inside to the outside with the guide member 23 as a reference. Figure 2 shown.

[0064] Figure 2 In the embodiment, the movable end 22 and the connected retaining ring 10 are in a low position, namely, a 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 The partial enlarged view of point A in the middle is used to more clearly reflect the positional relationship between adjacent components.

[0065] Among them, the first protective sleeve 31 is a cylindrical structure with a single-end opening and the opening is set downward. It is sleeved on the outer peripheral side of the guide tube 23b, and the first protective sleeve 31 is connected to the movable end 22, so that the first protective sleeve 31 can move up and down synchronously with the movable end 22, so as to provide protection for the movable end 22 and a partial area of ​​the guide tube 23b.

[0066] The second protective sleeve 32 is a cylindrical structure with two ends opened, and is arranged at intervals outside the first protective sleeve 31; the second protective sleeve 32 is sleeved on the outer peripheral side of the first protective sleeve 31, and the second protective sleeve 32 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 tube 23b.

[0067] Furthermore, the second protective sleeve 32 includes a fixing flange 32a, which is disposed above the guide seat 23a, and the fixing flange 32a 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 the polishing waste liquid may splash onto the outer peripheral side of the guide cylinder 23b.

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

[0069] Figure 5 It is a schematic diagram of a moving end 22 provided by an embodiment of the present invention moving to a high position with a retaining ring 10. 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 cover 31 and the second protective cover 32 are spaced apart from each other to avoid interference between components, thereby ensuring smooth up and down movement of the moving end 22 .

[0071] Depend on Figure 5 It can be seen that a second gap G2 (opening upward) is formed between the first protective cover 31 and the second protective cover 32. Figure 3 As shown in the figure, 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 movable end 22 moves up and down, the liquid attached 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 along the movable end 22 to the lower frame and contaminate the corresponding parts of the CMP system.

[0072] In order to solve the above technical problems, the polishing protection device of the present invention is further configured with a third protection sleeve 33. The third protection sleeve 33 is a cylindrical structure with a single end opening, which is opened downward and is spaced apart from the outside of the second protection sleeve 32.

[0073] Specifically, the third protective sleeve 33 is sleeved on the outer peripheral side of the second protective sleeve 32 to form a third gap G3 between the third protective sleeve 33 and the second protective sleeve 32. Figure 3 The third gap G3 is arranged downward, and the liquid splashed onto the third protective cover 33 will slide downward due to gravity and will hardly enter the second gap G2, thereby preventing the polishing waste liquid from moving toward the inner side where the moving end 22 is located.

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

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

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

[0077] At the same time, when the movable end 22 of the lifting assembly 20 drives the retaining ring 10 to move upward to the working position, the first protective cover 31, the second protective cover 32 and the third protective cover 33 overlap in the vertical direction, and the three are combined with each other to form a strict waterproof system, thereby inhibiting the polishing waste liquid from moving toward the inside of the lifting assembly 20.

[0078] It should be noted that consumables such as bellows can also be used instead of the protective cover 30, but there is a risk of aging and damage to consumables. Taking the bellows as an example, if the bellows is directly sleeved on the outside of the lifting assembly 20 and fixed to the moving end 22, the bellows will reciprocate up and down. If the number of expansions and contractions exceeds the service life, the bellows will be damaged and waterproof failure will occur. This waterproof failure is not easy to detect, and it is easy to cause water leakage in the lower frame of the CMP system, affecting the safety of the CMP system.

[0079] Compared with the technical solution of using consumables such as bellows alone, the protective cover 30 provided by the present invention is a processing component, which does not have the risk of aging and damage, and effectively ensures the protective effect of the lifting assembly 20; at the same time, there is no problem of regular replacement of processing components, which is conducive to reducing the workload of CMP system maintenance operations.

[0080] Figure 4 2 is a schematic diagram of a guide tube 23b provided in an embodiment of the present invention. In this embodiment, an annular protrusion 23b-1 is arranged on the outer peripheral side of the guide tube 23b, and the protrusion 23b-1 is integrally formed with the guide tube 23b.

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

[0082] The transverse 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 tube 23b can move smoothly in the first protective sleeve 31. In some embodiments, the transverse dimension of the protrusion 23b-1 is 2-8 mm.

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

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

[0085] If there is no vertical overlap between the guide tube 23 b and the first protective sleeve 31 , the first gap G1 is destroyed, and a small amount of polishing waste liquid may move to the movable end 22 through the third gap G3 and the second gap G2 in sequence, which is not conducive to ensuring the waterproofness of the lifting assembly 20 .

[0086] Figure 4 In the embodiment shown, the number of protrusions 23b-1 is a pair, which are arranged at intervals in the vertical direction on the upper part of the guide cylinder 23b. Usually, an annular protrusion 23b-1 is arranged on the top of the guide cylinder 23b. Such arrangement is conducive to controlling the vertical dimension of the guide cylinder 23b so that the guide cylinder 23b cooperates with the first protective sleeve 31 to form the first gap G1.

[0087] In the present invention, the outer peripheral side of the guide tube 23b is a tapered structure, and the outer diameter of the upper end is smaller than the outer diameter of the lower end, so that the first gap G1 ( Figure 3 As shown, the gap G1 gradually becomes smaller from top to bottom, thereby increasing the difficulty of the polishing waste liquid moving 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 illustrated embodiment, the guide seat 23 a is a disc-shaped structure, and the protective cover 30 is disposed above the guide seat 23 a.

[0089] Furthermore, a drain groove 23a-1 is disposed above the guide seat 23a, and the drain groove 23a-1 is used to drain the liquid that falls through the protective sleeve 30 and the guide cylinder 23a, so that a very small amount of liquid that enters the interior through the protective sleeve 30 is discharged to the outside of the CMP system through the drain groove 23a-1 to prevent the liquid from affecting the safe operation of other components in the CMP system. It should be noted that the drain groove 23a-1 is horizontally opened on the guide seat 23a, such as Figure 1 As shown, the liquid is quickly discharged to the base 1100 with a certain slope, and then the liquid is guided to the waste liquid outlet to prevent the liquid from accumulating outside the guide seat 23a and causing the liquid level to rise and flow back into the interior of the guide tube 23b.

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

[0091] Since the guide tube 23b is a tapered structure with a small top and a large 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 entering between the second protective sleeve 32 and the guide tube 23b can quickly enter the drainage groove 23a-1.

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

[0093] Figure 6 3 is a schematic diagram of a lifting assembly 20 provided with a protective cover 30 according to another embodiment of the present invention. Figure 2 The technical solutions shown have similarities, and the differences between the two technical solutions are mainly introduced below.

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

[0095] Meanwhile, the guide tube 23 b is a cylindrical structure, and at least one sealing groove is arranged on its outer circumference for installing the sealing ring 24 , so that the first protective sleeve 31 is connected to the guide tube 23 b in a sliding and sealing manner through the sealing ring 24 .

[0096] In this embodiment, there are two mounting grooves, which are arranged at the upper part of the guide cylinder 23b, and the mounting grooves are spaced apart along the vertical direction of the guide cylinder 23b to install corresponding sealing rings 24 to achieve 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, Figure 7 As shown, the sealing ring 24 is located at the vertical overlapping section of the guide tube 23b and the first protective sleeve 31 to prevent the guide tube 23b and the first protective sleeve 31 from being separated from each other and causing waterproof failure.

[0098] Furthermore, the guide seat 23 a of the guide member 23 is a disc-shaped structure, and a liquid drain groove 23 b is disposed above the guide seat 23 a to drain the liquid that falls through the protective sleeve 30 and the guide tube 23 b. Figure 6 The function of the middle drain groove 23b is Figure 2 The same as in the embodiment will not be repeated here.

[0099] It should be noted that, in the present invention, the protective cover 30 is made of corrosion-resistant materials, such as polyoxymethylene (POM), etc. At the same time, the surface of the material made of the protective cover 30 has a certain degree of hydrophobicity, especially the third protective cover 33 located on the outermost side, thereby preventing liquid from adhering to the surface of the protective cover 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, and the second protective sleeve 32 is made of plastic, such as POM. This arrangement allows the materials of adjacent protective sleeves 30 to be different, so as to avoid the protective sleeves 30 made of the same material from sticking to each other and affecting the smoothness of the movement of the components.

[0101] At the same time, the present invention also provides a chemical mechanical polishing system 1000, the schematic diagram of which is as follows: Figure 8 The chemical mechanical polishing system 1000 includes a polishing plate 200, a carrier head 300, a liquid supply device 400 and a trimming device 500, and further includes Figure 1 The polishing protection device 100 is shown, and the polishing protection device 100 is arranged on the outside of the polishing disc 200 to control the polishing waste liquid and / or cleaning water centrifugally ejected.

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

[0103] The polishing protection device 100 is disposed on the outer peripheral side of the polishing plate 200. The lifting assembly 20 ( Figure 1 The lifting assembly 20 is provided with a protective sleeve 30 , which can prevent the 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 means that the polishing liquid adheres to the inner wall of the movable end 22, and then flows along the movable end 22 to the interior of the guide cylinder 23b, and then flows to the fixed end 21 and its interior. These polishing waste liquids will flow along the lifting assembly 20 to the lower frame of the CMP system, causing water to enter the components in the corresponding area of ​​the lower frame.

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

[0106] Those of ordinary skill in the art will appreciate that the units and method steps of each example 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 performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present application.

[0107] The above implementation methods are only used to illustrate the embodiments of the present application, and are not limitations on the embodiments of the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present application. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present application. The scope of patent protection of the embodiments of the present application should be limited by the claims.

Claims

1. A polishing protection device for protecting a polishing disc in a polishing system, characterized in that: include: A retaining ring of an annular structure, arranged on the outer peripheral side of the polishing disc; A lifting assembly, the fixed end of which is connected to the base of the polishing system, and the movable end of which is connected to the retaining ring to drive the retaining ring to move vertically; The lifting component is provided with a protective cover to prevent polishing waste liquid from entering the interior of the lifting component.

2. The polishing protection device according to claim 1, characterized in that: The lifting assembly includes a guide member, which is sleeved on the outer peripheral side of the moving end, and the protective sleeve is arranged on the outer peripheral side of the guide member.

3. The polishing protection device according to claim 2, characterized in that: The guide member 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 arranged above the guide seat and is slidably connected to the outer peripheral side of the moving end.

4. The polishing protection device according to claim 3, characterized in that: The protective sleeve comprises a first protective sleeve which is sleeved on the outer peripheral side of the guide tube, and the first protective sleeve is connected to the movable end.

5. The polishing protection device according to claim 4, characterized in that: The protective sleeve comprises a second protective sleeve which is sleeved on the outer peripheral side of the first protective sleeve and fixed to the base.

6. The polishing protection device according to claim 5, characterized in that: The protective sleeve includes a third protective sleeve, which is sleeved on the outer peripheral side of the second protective sleeve and fixed to the moving end.

7. The polishing protection device according to claim 4, characterized in that: An annular protrusion is disposed on the outer peripheral side of the guide tube, and the number of the protrusion is at least one and the protrusion is disposed on the upper part of the guide tube.

8. The polishing protection device according to claim 7, characterized in that: The outer peripheral side of the guide tube is a tapered structure, and the outer diameter of the upper end is smaller than the outer diameter of the lower end, so that the gap formed by the first protective sleeve and the guide tube gradually decreases from top to bottom.

9. The polishing protection device according to claim 8, characterized in that: When the movable end moves up to the working position with the retaining ring, the protrusion is located on the upper side of the lower end surface of the first protective sleeve.

10. The polishing protection device according to claim 4, characterized in that: The first protective sleeve is a cylindrical structure with an opening at one end, and the opening is arranged downward.

11. The polishing protection device according to claim 5, characterized in that: The second protective sleeve is a cylindrical structure with openings at both ends, and is arranged at intervals outside the first protective sleeve; the second protective sleeve includes a fixing flange, which is arranged above the guide seat.

12. The polishing protection device according to claim 6, characterized in that: The third protective sleeve is a tubular structure with an opening at one end, and its opening is downward and is arranged at intervals outside the second protective sleeve.

13. The polishing protection device according to claim 3, characterized in that: The guide seat is a disc-shaped structure, and the protective sleeve is arranged above the guide seat.

14. The polishing protection device according to claim 13, characterized in that: A liquid drain groove is arranged above the guide seat to drain the liquid that falls through the protective sleeve and the guide tube.

15. The polishing protection device according to claim 12, characterized in that: 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.

16. The polishing protection device according to claim 12, 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 surface of the first protective sleeve and the guide seat, between the upper end surface of the second protective sleeve and the top wall of the third protective sleeve, and between the lower end surface of the third protective sleeve and the fixed flange of the second protective sleeve.

17. The polishing protection device according to claim 4, characterized in that: The guide tube is a cylindrical structure, and at least one sealing groove for installing a sealing ring is configured on its outer circumference. The sealing groove is arranged on the upper part of the guide tube, and the first protective sleeve is slidingly and sealingly connected to the guide tube through the sealing ring.

18. The polishing protection device according to claim 17, characterized in that: The guide seat is a disc-shaped structure, and a liquid drain groove is arranged on the upper part thereof to discharge the liquid falling through the protective sleeve and the guide tube.

19. The polishing protection device according to claim 17, characterized in that: When the moving end of the lifting assembly drives the retaining ring to move upward to the working position, the sealing ring is located at the vertical overlapping section of the guide tube and the first protective sleeve.

20. A chemical mechanical polishing system, characterized in that: It includes a polishing disk, a carrying head, a liquid supply device and a trimming device. The carrying head presses the wafer to be polished against the polishing pad above the polishing disk, the liquid supply device supplies polishing liquid between the polishing pad and the wafer, and the trimming device is used to trim the surface of the polishing pad. It also includes the polishing protection device according to any one of claims 1 to 19 to prevent polishing waste liquid from entering the interior of the lifting assembly.

21. A polishing method, characterized in that: Polishing is carried out using the chemical mechanical polishing system described in claim 20, and the lifting component of the polishing protection device is provided with a protective cover to prevent polishing waste liquid from entering the interior of the lifting component.

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