A chemical mechanical polishing method

Abstract

This invention discloses a chemical mechanical polishing (CMP) method, comprising: a first carrier head configured in a polishing assembly loading a wafer from a loading / unloading stage and moving it to a polishing pad to perform CMP on the wafer; during the movement of the first carrier head toward the polishing pad, a wafer transfer robot places the next wafer on the loading / unloading stage; a second carrier head configured in the polishing assembly moving to the loading / unloading stage and loading the wafer; a fluid delivery component of a humidification mechanism connecting to a protective component on the upper side of the second carrier head and delivering fluid toward the protective component to form a water curtain below the protective component; after the first carrier head completes polishing, the fluid delivery component stops supplying fluid and separates from the protective component, and the second carrier head loaded with the wafer moves to the polishing pad to perform CMP on the wafer.

Description

Technical Field

[0001] This invention belongs to the field of chemical mechanical polishing technology, and more specifically, relates to a chemical mechanical polishing method. Background Technology

[0002] Chemical mechanical polishing (CMP) is an ultra-precision surface processing technology that achieves global planarization. It is a key technology in wafer manufacturing and plays a crucial role in promoting the digital and intelligent transformation and upgrading of the manufacturing industry.

[0003] Chemical mechanical polishing typically involves holding the wafer to the bottom of a support head, with the side of the wafer having the deposited layer abutting 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 component, 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 polishing pad, allowing the wafer to undergo chemical mechanical polishing under the combined action of chemicals and machinery.

[0004] During the polishing process, the surfaces of the devices inside the polishing unit need to be kept moist to prevent polishing fluid and / or particles from adhering to the device surface and crystallizing. These crystals may fall off during the polishing operation and cause scratches on the wafer.

[0005] In existing technologies, a spraying component is installed inside the polishing unit to moisturize the internal components. However, this moisturizing method can cause fluid backsplashing, resulting in fluid containing particulate matter splashing onto other components and affecting the moisturizing effect inside the polishing unit. Summary of the Invention

[0006] This invention provides a chemical mechanical polishing method, which aims to at least solve one of the technical problems existing in the prior art.

[0007] An embodiment of the present invention provides a chemical mechanical polishing method, comprising:

[0008] S1, the first carrier head of the polishing assembly loads the wafer onto the self-loading stage and moves it to the polishing pad to perform chemical mechanical polishing on the wafer;

[0009] S2, as the first carrier head moves toward the polishing disk, the wafer transfer robot places the next wafer on the loading and unloading table;

[0010] S3, the second carrier head of the polishing assembly moves to the loading / unloading stage and loads the wafer;

[0011] S4, the fluid delivery component of the humidification mechanism is connected to the protective component on the upper side of the second bearing head, and fluid is delivered toward the protective component to form a water curtain below the protective component;

[0012] S5, after the first carrier head completes polishing, the liquid supply component stops supplying liquid and separates from the protective component, and the second carrier head loaded with the wafer moves to the polishing pad to perform chemical mechanical polishing on the wafer.

[0013] In some embodiments, after the first carrier head / second carrier head moves to the loading / unloading platform, the infusion component of the humidification mechanism is connected to the protective component, and the infusion component begins to supply fluid.

[0014] In some embodiments, an annular water curtain is formed below the protective member, covering the outside of the first support head / second support head.

[0015] In some embodiments, the water curtain is arranged from top to bottom, and the lateral distance between it and the outer periphery of the first support head / second support head is 0-3mm.

[0016] In some embodiments, the fluid supplied toward the protective member comprises deionized water at a temperature above room temperature.

[0017] In some embodiments, the polishing assembly includes a rotating component, a support frame, a first bearing head, and a second bearing head. The rotating component is connected to the support frame, and the first and second bearing heads are suspended below the support frame by a fixing component. The rotating component can drive the support frame to rotate about a vertical axis, thereby moving the first / second bearing head between the loading / unloading table and the polishing disc. The protective component is connected to the fixing component.

[0018] In some embodiments, the support frame is provided with a linear module along its length, and the fixing member is slidably connected to the support frame through the linear module; the first bearing head / second bearing head can move in the horizontal direction to drive the protective member toward or away from the infusion device.

[0019] In some embodiments, during the rotation of the support frame, the first bearing head / second bearing head moves in advance along the length direction of the support frame, so that the protective member moving toward the loading and unloading platform is inserted and fixed with the infusion member.

[0020] In some embodiments, the infusion unit is disposed adjacent to the loading / unloading platform, and the moisturizing mechanism moisturizes the first carrier head / second carrier head at the loading / unloading platform.

[0021] In some embodiments, the infusion device is configured with a moving module that can move the infusion device toward or away from the protective device.

[0022] In some embodiments, the protective member is a ring-shaped structure with an annular liquid outlet at its lower end to form an annular water curtain below the protective member.

[0023] In some embodiments, the width of the outlet is 0.5-3 mm, and the flow rate of the infusion device is greater than or equal to 100 mL / min.

[0024] The beneficial effects of this invention include:

[0025] a. When the bearing head of the polishing assembly moves to the loading and unloading platform, the fluid delivery component of the moisturizing mechanism is inserted and fixed to the protective component and delivers fluid. A water curtain is formed under the protective component and covers the outer periphery of the bearing head to moisturize the components under the protective component and prevent polishing particles from crystallizing on the outside of the bearing head.

[0026] b. The moisturizing mechanism has a reasonable structure, in which the protective component is integrated on the upper side of the bearing head, and the infusion component is detachably connected to the protective component, which effectively reduces space occupation and improves the convenience of operation inside the polishing module;

[0027] c. During the rotation of the support frame and the bearing head, the protective component moves with the bearing head in advance to improve the docking efficiency between the protective component and the infusion component, thereby achieving efficient moisturization of the bearing head. Attached Figure Description

[0028] The advantages of the present invention will become clearer and easier to understand through the following detailed description in conjunction with the accompanying drawings, which are merely illustrative and do not limit the scope of protection of the present invention, wherein:

[0029] Figure 1 This is a schematic diagram of a chemical mechanical polishing system provided in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of a polishing module provided in an embodiment of the present invention;

[0031] Figure 3 yes Figure 2 A magnified view of a section at point A in the middle;

[0032] Figure 4 This is a flowchart of a chemical mechanical polishing method provided in an embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0034] The accompanying drawings in this specification are schematic diagrams used to illustrate the concept of the invention and to schematically show the shapes of the various parts and their interrelationships. It should be understood that, in order to clearly show the structure of the various components of the embodiments of the invention, the drawings are not drawn to the same scale, and the same reference numerals are used to indicate the same parts in the drawings.

[0035] In this invention, "Chemical Mechanical Polishing (CMP)" is also called "Chemical Mechanical Planarization (CMP)," and the wafer (W) is also called the substrate (Substrate), with the same meaning and actual function.

[0036] The embodiments disclosed in this invention generally relate to chemical mechanical polishing (CMP) methods used in the semiconductor device manufacturing industry. To more clearly illustrate the chemical mechanical polishing method provided by this invention, the chemical mechanical polishing system used in this invention is first briefly described.

[0037] Figure 1 This is a schematic diagram of a chemical mechanical polishing system provided in an embodiment of the present invention, which includes:

[0038] Front unit 1 is used to store wafers to be polished and wafers that have been polished;

[0039] Polishing unit 3 is used for material removal from the wafer surface;

[0040] The cleaning unit 2 is located between the pre-processing unit 1 and the polishing unit 3 and is used to clean the wafer surface to remove residual particles on the wafer surface.

[0041] The polishing unit 3 is the core component of the CMP system. The polishing unit 3 includes multiple polishing modules 30 and a wafer transfer mechanism 4. The polishing modules 30 of the polishing unit 3 are arranged around the wafer transfer mechanism 4 to facilitate the transfer of wafers between the various polishing modules 30, meeting the requirements of multiple polishing processes.

[0042] Figure 1 In the embodiment shown, the polishing unit 3 includes four polishing modules 30, namely: polishing module 30A, polishing module 30B, polishing module 30C and polishing module 30D. Each polishing module 30 is arranged horizontally along the length of the polishing unit 3.

[0043] Figure 1In this design, the wafer transfer mechanism 4 includes a pair of wafer transfer robots 41. One robot 41 is responsible for transferring wafers between polishing modules 30A and 30B; the other robot 41 is responsible for transferring wafers between polishing modules 30C and 30D. One robot 41, polishing modules 30A and 30B form a first polishing unit, and the other robot 41, polishing modules 30C and 30D form a second polishing unit. The first and second polishing units are symmetrically arranged along the centerline of the polishing unit 3 and operate independently of each other, preventing the entire polishing unit 3 from malfunctioning due to a failure of one polishing module 30, thus improving the fault tolerance of the polishing unit 3. It should be noted that the wafer transfer mechanism 4 includes at least one wafer transfer robot 41, which can be equipped with multiple wafer grippers to meet the wafer transfer operations in the polishing unit 3.

[0044] Furthermore, the wafer transfer mechanism 4 also includes an infeed / outfeed buffer device 42 and an intermediate buffer device 43, which are arranged along the length of the polishing unit 3; and the infeed / outfeed buffer device 42 and the intermediate buffer device 43 are respectively located on both sides of the wafer transfer robot 41. Specifically, the infeed / outfeed buffer device 42 is arranged horizontally adjacent to the cleaning unit 2 to buffer the wafers to be processed between the polishing unit 3 and the cleaning unit 2; the intermediate buffer device 43 is arranged on the other side of the wafer transfer robot 41 and is located between the polishing module 30B and the polishing module 30D.

[0045] Figure 2 This is a schematic diagram of a polishing module 30 provided in an embodiment of the present invention. The polishing module 30 includes:

[0046] Polishing disc 31, on which a polishing pad is provided;

[0047] Polishing assembly 32 is used for wafer polishing and handling;

[0048] And a loading and unloading stage 33 for loading and unloading wafers; the loading and unloading stage 33 is disposed on the outside of the polishing disk 31; the polishing assembly 32 is disposed on the upper side of the polishing disk 31 and the loading and unloading stage 33 to transfer wafers between the polishing disk 31 and the loading and unloading stage 33 and to abut the wafers against the polishing pad above the polishing disk 31 to perform chemical mechanical polishing.

[0049] Figure 2In the polishing module 30, there are also a dresser 34 and a liquid supply arm 35. The dresser 34 can swing around a fixed point located outside the polishing disk 31; the dressing disk of the dresser 34 rotates itself and applies a downward load to dress the surface of the polishing pad; the liquid supply arm 35 is disposed above the polishing pad to distribute the polishing liquid on the surface of the polishing pad according to the process requirements.

[0050] Figure 2 In the illustrated embodiment, the polishing assembly 32 includes a support frame 32a, a rotating component 32b, and a bearing head 32c. The bearing head 32c is suspended below the support frame 32a. The rotating component 32b is connected to the support frame 32a and can rotate to move the bearing head 32c between the loading / unloading stage 33 and the polishing disk 31. The bearing head 32c can move along the length of the support frame 32a, so that the bearing head 32c rotates around its axis while moving radially along the polishing disk 31, realizing the reciprocating motion of the bearing head 32c to reduce the radial difference of the polishing pad on the polishing disk 31 and complete the global planarization of the wafer.

[0051] Figure 2 In the polishing assembly 32, the carrier head 32c includes a first carrier head 32c-1 and a second carrier head 32c-2. That is, the first carrier head 32c-1 and the second carrier head 32c-2 can be collectively referred to as carrier head 32c.

[0052] As an embodiment of the present invention, the polishing module 30 further includes a moisturizing mechanism 36, which is disposed above the bearing head 32c to moisturize the bearing head 32c and prevent polishing particles from forming crystals on the outer periphery of the bearing head 32c.

[0053] Figure 2 In the illustrated embodiment, the humidification mechanism 36 includes an infusion component 36a and a protective component 36b. The protective component 36b covers the upper side of the support head 32c. The infusion component 36a can be detachably connected to the protective component 36b to deliver fluid toward the protective component 36b. The fluid introduced can form a water curtain on the outer periphery of the support head 32c. Figure 2 The water curtain in the diagram is represented by a dashed line to moisturize the components below the protective part 36b and prevent polishing particles from adhering to the surface of the components and crystallizing.

[0054] Preferably, when the bearing head 32c rotates to the loading and unloading platform 33, the infusion component 36a can be fixed together with the protective component 36b by plugging in, so that the fluid can be transported through the infusion component 36a to the interior of the protective component 36b, thereby forming a water curtain on the outer periphery of the bearing head 32c.

[0055] Figure 2In the illustrated embodiment, the protective component 36b is a protective main body, which has a ring-shaped structure, and the lower end of the protective main body is provided with Figure 3 The liquid outlet 36b-1 shown is designed to form an annular water curtain below the protective element 36b.

[0056] Figure 3 yes Figure 2 The enlarged view at point A shows that the interior of the protective main body is provided with a concentric annular groove 36b-2, and the lower part of the annular groove 36b-2 is connected to the liquid outlet 36b-1.

[0057] Figure 3 In the middle, a connecting hole 36b-3 is provided on the outer periphery of the protective body. The connecting hole 36b-3 is arranged horizontally and communicates with the annular groove 36b-2. The end of the infusion component 36a is connected to the connecting hole 36b-3 so as to transport the fluid through the connecting hole 36b-3 to the annular groove 36b-2, and then discharge it through the outlet 36b-1 provided at the lower part of the protective component 36b to form a moisturizing water curtain.

[0058] Figure 2 In the middle, the bearing head 32c is suspended below the support frame 32a by the fixing member 32d. The fixing member 32d is connected to the support frame 32a through the linear module 32e, so that the linear module 32e can drive the bearing head 32c to move along the length direction of the support frame 32a through the fixing member 32d, so as to move the protective member 36b set above the bearing head 32c toward the infusion member 36a, thereby realizing the connection between the protective member 36b and the infusion member 36a.

[0059] Figure 2 In the embodiment shown, the infusion component 36a is positioned above the loading and unloading platform 33 and its position is relatively fixed. By controlling the movement of the fixing component 32d, the protective component 36b is moved toward the infusion component 36a, thereby achieving the insertion and fixing of the two.

[0060] Figure 2 In the illustrated embodiment, when the bearing head 32c rotates and swings to the loading / unloading platform 33, the bearing head 32c is approximately above the loading / unloading platform 33. At this time, it is necessary to keep the components below the protective member 36b moist. It is understood that the components below are not limited to the bearing head 32c, but also include components such as the loading / unloading platform 33.

[0061] In another embodiment of the present invention, the infusion component 36a can also be disposed on the movable module. Figure 2 (Not shown) is used to move the infusion component 36a toward or away from the protective component 36b via a moving module, thereby connecting or separating the infusion component 36a from the protective component 36b.

[0062] As a variation of this embodiment, the infusion component 36a and the fixing component 32d can also be controlled to move simultaneously towards each other to achieve a connection and fixation between the infusion component 36a and the protective component 36b. In this case, the displacement of the connection hole 36b-3 of the infusion component 36a and the protective component 36b is matched to facilitate accurate connection between the two. When it is necessary to separate the infusion component 36a and the protective component 36b, the efficiency of separation can be improved by controlling the infusion component 36a and the fixing component 32d to move in opposite directions.

[0063] Figure 2 In the illustrated embodiment, the moisturizing mechanism 36 adopts a detachable structure, which effectively simplifies the structure, reduces the space occupied by the moisturizing mechanism 36, and improves the convenience of various operations inside the polishing module 30. At the same time, the moisturizing mechanism 36 forms a ring-shaped water curtain from top to bottom. The water curtain has a smaller impact on the various components inside the polishing module 30, avoiding the problem of secondary pollution caused by fluid splashing, and thus improving the overall moisturizing effect inside the polishing module 30.

[0064] Figure 4 This is a flowchart of a chemical mechanical polishing method provided in an embodiment of the present invention, which is described below in conjunction with... Figure 2 The illustrated chemical mechanical polishing system demonstrates the operation of polishing module 30. A chemical mechanical polishing method includes:

[0065] S1, the first carrier head 32c-1 of the polishing assembly 32 is loaded onto the wafer by the self-loading stage 33 and moved to the polishing disk 31 to perform chemical mechanical polishing on the wafer;

[0066] Specifically, the rotating component 32b drives the support frame 32a to rotate around the vertical axis, so as to move the first bearing head 32c-1 suspended on the support frame 32a from the loading and unloading table 33 to above the polishing pad 31. The first bearing head 32c-1 presses the loaded wafer against the polishing pad above the polishing pad 31 to perform chemical mechanical polishing.

[0067] S2, as the first carrier head 32c-1 moves toward the polishing disk 31, the wafer transfer robot 41 places the next wafer onto the loading and unloading stage 33.

[0068] It should be noted that before the wafer transfer robot 41 places the next wafer to be polished, the polished wafers on the loading / unloading stage 33 must first be transferred to the next process before the next wafer is placed. During the movement of the carrier head 32c, the wafer transfer robot 41 completes the wafer transfer to reduce waiting time and improve work efficiency.

[0069] S3, the second carrier head 32c-2 configured in the polishing assembly 32 moves to the loading / unloading stage 33 and loads the wafer;

[0070] Specifically, the second carrier head 32c-2 cooperates with the loading and unloading stage 33 to complete the loading of the wafer according to the set process parameters.

[0071] S4, the infusion component 36a of the humidification mechanism 36 is connected to the protective component 36b on the upper side of the second bearing head 32c-2, and fluid is delivered toward the protective component 36b to form a water curtain below the protective component 36b;

[0072] Specifically, the second carrier head 32c-2 moves along the length of the support frame 32a under the drive of the linear module 32e. The protective member 36b set on the fixing member 32d moves toward the infusion member 36a, so that the end of the infusion member 36a is inserted into the connection hole 36b-3 of the protective member 36b to deliver fluid to the interior of the protective member 36b, so as to form an annular water curtain below the protective member 36b to prevent polishing particles from adhering to the surface of the carrier head 32c and its lower components, and to avoid crystal falling off and scratching the wafer.

[0073] S5, after the first carrier head 32c-1 completes polishing, the liquid supply component 36a stops supplying liquid and separates from the protective component 36b, and the second carrier head 32c-2, which is loaded with wafers, moves to the polishing disk 31 to perform chemical mechanical polishing on the wafers.

[0074] Specifically, after the wafer loaded on the first carrier head 32c-1 is polished according to the set process parameters, the rotating part 32b drives the support frame 32a to rotate, so as to transfer the first carrier head 32c-1 from the polishing disk 31 to the loading and unloading stage 33.

[0075] Before the bearing head 32c changes position, the moisturizing action of the moisturizing mechanism 36 needs to be stopped. Specifically, the fluid supply to the infusion unit 36a is stopped, and the fixing member 32d is controlled to move away from the infusion unit 36a, so that the protective member 36b separates from the infusion unit 36a.

[0076] As an embodiment of the present invention, after the bearing head 32c moves to the loading and unloading platform 33, the liquid infusion component 36a of the moisturizing mechanism 36 is connected to the protective component 36b, and the liquid infusion component 36a begins to supply liquid toward the protective component 36b to form a circumferentially closed water curtain in the protective component 36b, ensuring that the surface of the components inside the water curtain is in a moist state.

[0077] Furthermore, the water curtain formed by the humidification mechanism 36 is a ring-shaped water curtain, which covers the outside of the first support head 32c-1 / second support head 32c-2, so as to ensure that the internal components of the water curtain are in a good humidification state.

[0078] It should be noted that the infusion component 36a of the moisturizing mechanism 36 should avoid the path setting of the wafer transfer robot 41 to grasp the wafer, so as to avoid interference between the wafer transfer robot 41 and the wafer it grasps and the infusion component 36a, which would affect the execution of the wafer polishing process.

[0079] In this invention, the annular groove 36b-2 ( Figure 3 As shown, the fluid in the image flows out from the outlet 36b-1 under the influence of gravity, forming a water curtain from top to bottom. This design helps control the splashing of the moisturizing fluid, avoids or mitigates problems caused by secondary splashing, and ensures a good working environment inside the polishing module 30.

[0080] Preferably, the water curtain formed by the moisturizing mechanism 36 is located on the outer periphery of the bearing head 32c, that is, the annular water curtain is flush with the outer periphery of the bearing head 32c, so as to ensure that the components inside the annular water curtain are kept moist. At the same time, the formation of the water curtain can also block some polishing particles from splashing into the interior of the water curtain.

[0081] Because the support head 32c is sealed to the flange end by clamps, assembly errors may occur during installation. Therefore, the water curtain formed may not be able to guarantee complete concentricity with the outer periphery of the support head 32c. If the water curtain is not concentric with the support head 32c, the water will splash onto the upper surface of the support head 32c and backflow, thus failing to form a relatively complete water curtain.

[0082] To reduce or avoid the aforementioned problems, the water curtain formed by the humidification mechanism 36 needs to be positioned on the outside of the support head 32c. Preferably, the lateral distance between the water curtain and the outer periphery of the support head 32c is 0-3mm to eliminate the influence of assembly errors of the support head 32c on the integrity of the water curtain formation.

[0083] In this invention, to form a relatively complete water curtain and achieve a good moisturizing effect, the vertical distance between the protective component 36b and the bearing head 32c should be less than or equal to 200mm. Here, the vertical distance refers to the distance between the lower end face of the protective component 36b and the protective cover of the bearing head 32c.

[0084] Figure 2 In the illustrated embodiment, the infusion unit 36a is disposed adjacent to the loading / unloading platform 33, and the humidification mechanism 36 humidifies the carrier head 32c on the loading / unloading platform 33. That is, after the carrier head 32c moves to the position of the loading / unloading platform 33, the infusion unit 36a needs to be quickly inserted into the protective member 36b disposed on the upper side of the carrier head 32c to form a ring-shaped water curtain below the protective member 36b.

[0085] In order to improve the insertion efficiency of the protective component 36b and the infusion component 36a, during the rotation of the support frame 32a, the first bearing head 32c-1 / second bearing head 32c-2 are pre-moved along the length of the support frame 32a, so that the protective component 36b moving toward the loading and unloading platform 33 can be quickly inserted and fixed together with the infusion component 36a, so as to open the annular groove 36b-2 of the infusion component 36a to deliver fluid toward the protective component 36b.

[0086] As an embodiment of the present invention, the width of the liquid outlet 36b-1 provided on the protective member 36b is 0.5-3mm, and the flow rate of the infusion member 36a is greater than or equal to 100mL / min, so that a relatively complete water curtain is formed below the protective member 36b.

[0087] Because the outlet 36b-1 is arranged circumferentially along the protective component 36b and is relatively small, in order to achieve a ring-shaped water curtain and ensure good moisturizing effect, it is necessary to precisely control the width of the outlet 36b-1, especially to ensure the uniformity of the circumferential width of the outlet 36b-1.

[0088] In one embodiment of the present invention, the protective member 36b includes a protective main body and an annular protective plate, the annular protective plate being disposed on the outside of the protective main body to form a liquid outlet 36b-1. In one aspect of this embodiment, the width of the liquid outlet 36b-1 can be adjusted by controlling the machining precision of the annular protective plate.

[0089] Preferably, a strip-shaped boss structure can be provided on the inner wall of the annular guard plate, and the boss structure is located on the outer periphery of the protective body. The boss structure is arranged along the length direction of the annular guard plate, and the number of boss structures is 2 or 4, which are evenly distributed along the circumference of the annular guard plate. By precisely controlling the processing accuracy of the boss structure, the gap size between the inner wall of the annular guard plate and the outer wall of the protective body can be effectively guaranteed, thereby controlling the circumferential size of the liquid outlet 36b-1 to form a relatively complete annular water curtain.

[0090] As one aspect of this embodiment, the fluid conveyed toward the protective component 36b contains deionized water at a temperature higher than room temperature, such as 35-45°C. This improves the fluid's flow characteristics and enhances its moisturizing effect by dissipating heat outwards. Simultaneously, the deionized water at a higher temperature can, to some extent, alter the surface temperature of the carrier head 32c and the wafer it holds, bringing the wafer surface temperature closer to that of the polishing pad. This reduces or eliminates the impact of temperature changes on the polishing removal rate, ensuring a good polishing effect.

[0091] In some embodiments, a sealing element is provided at the end of the infusion component 36a. When the infusion component 36a is inserted into the mounting hole of the protective component 36b, the sealing element is located on the outer end face of the infusion component 36a and the mounting hole to achieve a seal between the infusion component 36a and the protective component 36b, preventing the liquid delivered to the protective component 36b from leaking between the two and affecting the formation effect of the annular water curtain.

[0092] In this invention, the moisturizing mechanism 36 configured in the polishing module 30 can be positioned at the loading / unloading table 33. When the bearing head 32c rotates to the loading station, it is necessary to moisturize the bearing head 32c and its lower components. The protective component 36b, located on the fixing component 32d, moves toward the liquid delivery component 36a of the moisturizing mechanism 36, and the two quickly dock to deliver fluid to the protective component 36b through the liquid delivery component 36a. A ring-shaped water curtain is formed below the protective component 36b to moisturize the bearing head 32c and its lower components, preventing particles in the polishing module 30 from adhering to the surface of the components and crystallizing.

[0093] It should be noted that once the carrier head 32c moves above the loading / unloading platform 33, the fluid delivery component 36a of the humidification mechanism 36 can dock with the protective component 36b and introduce fluid towards the protective component 36b, without waiting for the wafer transfer robot 41 to complete the wafer transfer. That is, the annular water curtain formed by the humidification mechanism 36 will not negatively affect the normal transfer of the wafer. Furthermore, an annular water curtain is formed below the protective component 36b, covering the outside of the carrier head 32c. The carrier head 32c can normally load wafers or rotate around its central axis; that is, the humidification mechanism 36 will not interfere with the various operational actions of the carrier head 32c.

[0094] The following is combined with Figure 1 Briefly describe the wafer transfer process in polishing unit 3:

[0095] The wafer transfer robot 41 can transfer wafers from the buffer device 42 to the loading / unloading stage 33 of the polishing module 30A; or, the wafer transfer robot 41 can transport polished wafers from the loading / unloading stage 33 to the buffer device 42; or, the wafer transfer robot 41 can transfer wafers from the loading / unloading stage 33 of the polishing module 30A to the loading / unloading stage 33 of the polishing module 30B; or, the wafer transfer robot 41 can transport wafers from the loading / unloading stage 33 of the polishing module 30A to the intermediate buffer device 43, and another wafer transfer robot 41 can then transfer wafers from the intermediate buffer device 43 to the polishing module 30C or the polishing module 30D.

[0096] exist Figure 2 When the load-bearing head 32c shown is moved above the loading / unloading platform 33, the moisturizing mechanism 36 can form a water curtain below the protective component 36b to moisturize the components below and prevent polishing particles from adhering to the surface of the components.

[0097] In this invention, the operator can use polishing module 30A alone to perform chemical mechanical polishing according to process requirements; or the operator can use polishing module 30A and polishing module 30B to perform polishing. That is, the operator can use polishing module 30A, polishing module 30B, polishing module 30C and / or polishing module 30D to perform chemical polishing, which is suitable for different types of polishing processes.

[0098] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0099] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A chemical mechanical polishing method, characterized in that, include: S1, the first carrier head of the polishing assembly loads the wafer onto the self-loading stage and moves it to the polishing pad to perform chemical mechanical polishing on the wafer; S2, as the first carrier head moves toward the polishing disk, the wafer transfer robot places the next wafer on the loading and unloading table; S3, the second carrier head of the polishing assembly moves to the loading / unloading stage and loads the wafer; S4, the fluid delivery component of the humidification mechanism is connected to the protective component on the upper side of the second bearing head, and fluid is delivered toward the protective component to form a water curtain below the protective component; S5, after the first carrier head completes polishing, the liquid supply component stops supplying liquid and separates from the protective component, and the second carrier head loaded with the wafer moves to the polishing pad to perform chemical mechanical polishing on the wafer; The polishing assembly includes a support frame, a first bearing head, and a second bearing head. The first bearing head and the second bearing head are suspended below the support frame by a fixing member, and the protective member is connected to the fixing member.

2. The chemical mechanical polishing method as described in claim 1, characterized in that, After the first bearing head / second bearing head moves to the loading and unloading platform, the fluid delivery component of the humidification mechanism is connected to the protective component, and the fluid delivery component begins to supply fluid.

3. The chemical mechanical polishing method as described in claim 1, characterized in that, A ring-shaped water curtain is formed below the protective component, covering the outside of the first bearing head / second bearing head.

4. The chemical mechanical polishing method as described in claim 3, characterized in that, The water curtain is arranged from top to bottom, and the lateral distance between it and the outer periphery of the first bearing head / second bearing head is 0-3mm.

5. The chemical mechanical polishing method as described in claim 1, characterized in that, The fluid being delivered toward the protective component contains deionized water at a temperature above room temperature.

6. The chemical mechanical polishing method as described in claim 1, characterized in that, The polishing assembly includes a rotating component connected to a support frame; the rotating component can drive the support frame to rotate around a vertical axis, thereby moving the first bearing head / second bearing head between the loading / unloading table and the polishing disc.

7. The chemical mechanical polishing method as described in claim 6, characterized in that, The support frame is provided with a linear module along its length, and the fixing member is slidably connected to the support frame through the linear module; the first bearing head / second bearing head can move in the horizontal direction to drive the protective member to move toward or away from the infusion member.

8. The chemical mechanical polishing method as described in claim 7, characterized in that, During the rotation of the support frame, the first bearing head / second bearing head moves in advance along the length direction of the support frame, so that the protective component moving toward the loading and unloading platform is inserted and fixed with the infusion component.

9. The chemical mechanical polishing method as described in claim 1, characterized in that, The infusion unit is disposed adjacent to the loading and unloading platform, and the moisturizing mechanism moisturizes the first bearing head / second bearing head at the loading and unloading platform.

10. The chemical mechanical polishing method as described in claim 1, characterized in that, The infusion unit is equipped with a moving module, which can move the infusion unit toward or away from the protective component.

11. The chemical mechanical polishing method as described in claim 1, characterized in that, The protective component has a ring-shaped structure with an annular liquid outlet at its lower end to form an annular water curtain below the protective component.

12. The chemical mechanical polishing method as described in claim 11, characterized in that, The width of the outlet is 0.5-3mm, and the flow rate of the infusion device is greater than or equal to 100mL / min.

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