Wafer carrier apparatus

Abstract

The application discloses a wafer carrier device, comprising: a rotating table assembly, comprising a support table and a pressing part, the support table is used for supporting a wafer, and the pressing part is used for pressing the wafer; a magnetic fluid shaft, comprising an inner shaft and an outer shaft, a magnetic fluid is arranged between the inner shaft and the outer shaft, the inner shaft comprises an end part and a cylindrical part, and the two parts enclose a containing space; a lifting assembly, comprising a main body part and a lifting body, the main body part is located in the containing space, the lifting body is slidably and sealingly assembled to the end part, and the lifting body is in action with the pressing part. The wafer carrier device can more fully utilize the internal space of the inner shaft, improve the structural compactness and integration of the equipment, effectively reduce the occupied space of the wafer carrier device, and facilitate installation.

Description

Technical Field

[0001] This invention relates to the field of wafer manufacturing technology, and more specifically to a wafer stage device. Background Technology

[0002] Ion beam etching and ion beam deposition are two common wafer fabrication processes. Ion beam etching uses ions with a certain energy to bombard the surface of the material, causing the material atoms to sputter, thereby achieving the etching purpose. It is a purely physical process. Ion beam deposition, on the other hand, uses an ion source to ionize the material to be deposited, and then, under the action of an electric field, it is directed onto the wafer surface to deposit a film layer. The purpose is to change the surface properties of the workpiece. It is a vapor phase deposition method.

[0003] In the process, the ion source is generally in a fixed position, and the processing position is adjusted by rotating the wafer, with the entire process taking place in a vacuum environment. Therefore, existing technologies include a stage device for supporting the wafer, which provides the driving force to meet the motion requirements of wafer processing.

[0004] However, existing platform devices generally suffer from being large in size and occupying a lot of space. Summary of the Invention

[0005] The purpose of this invention is to provide a wafer stage device with a highly compact structure that can effectively reduce the volume occupied.

[0006] To address the aforementioned technical problems, the present invention provides a wafer stage device, comprising: a rotary stage assembly including a support stage and a pressing part, wherein the support stage is used to support a wafer and the pressing part is used to press the wafer; a magnetic fluid shaft including an inner shaft and an outer shaft, wherein a magnetic fluid is disposed between the inner shaft and the outer shaft, the inner shaft including an end component and a cylindrical component, the two enclosing a receiving space; and a lifting assembly including a main body and a lifting body, wherein the main body is located in the receiving space, the lifting body is slidably and sealingly assembled to the end component, and the lifting body interacts with the pressing part.

[0007] With the above scheme, the outer shaft of the magnetohydrodynamic shaft is barrel-shaped, and its interior can form a receiving space. The main body of the lifting component used to drive the pressing part to move relative to the support platform is located in this receiving space. In this way, the internal space of the inner shaft can be utilized more fully to improve the structural compactness and integration of the equipment, and can effectively reduce the space occupied by the wafer stage device to facilitate installation.

[0008] Optionally, the main body includes a cylinder and a lifting plate. The cylinder has a piston rod connected to the lifting plate, and the lifting plate is connected to several lifting bodies.

[0009] Optionally, the main body also includes a bellows, with both ends of the bellows connected to the lifting plate and the end component, respectively, and the bellows sleeve is installed on the lifting body.

[0010] Optionally, the lifting assembly also includes a push pin, which is slidably and sealingly fitted to the end component.

[0011] Optionally, one of the lifting bodies and one of the ejector pins share a bellows for sealed assembly.

[0012] Optionally, the magnetohydrodynamic shaft is provided with a first cooling channel.

[0013] Optionally, it further includes: a housing assembly, the internal space of which is in communication with the atmospheric environment, the housing assembly including a support plate, the outer shaft seal being fitted onto the support plate; and a drive assembly, at least a portion of which is located within the housing assembly and is drively connected to the inner shaft.

[0014] Optionally, the drive assembly includes a stator, a mover, and a mounting member. The mover is connected to the inner shaft drive, and the mounting member is used to mount the drive assembly and is provided with a second cooling channel.

[0015] Optionally, the mounting component includes a first connecting part and a second connecting part connected together, the first connecting part being connected to the outer shaft, and a second cooling channel being formed between the first connecting part and the second connecting part.

[0016] Optionally, the first connecting part is provided with a first stop, and the second connecting part is provided with a second stop, and the stator is positioned and assembled by means of the first stop and the second stop.

[0017] Optionally, the support platform includes a hot platform section and a cold platform section.

[0018] Optionally, a third cooling channel is provided on the side of the cold table section facing the hot table section; it also includes a sealing section, which is disposed between the cold table section and the hot table section.

[0019] Optionally, it also includes a back helium section, which is located on the side of the support platform near the wafer.

[0020] Optionally, it also includes a rotary joint, which is connected to the end component.

[0021] Optionally, a transition plate is also included, through which the rotary joint is connected to the end component. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a specific embodiment of the wafer stage device provided by the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the structure of the magnetohydrodynamic shaft;

[0024] Figure 3 for Figure 1 Schematic diagram of the lifting assembly;

[0025] Figure 4 for Figure 1 Schematic diagram of the central support platform;

[0026] Figure 5 for Figure 1 A schematic diagram of the structure of the driving component.

[0027] Figures 1-5 The annotations in the accompanying drawings are explained as follows:

[0028] 1 housing assembly, 11 support plates;

[0029] 2 Rotary table assembly, 21 Support platform, 211 Hot stage section, 212 Cold stage section, 212a Third cooling channel, 212a-1 Inlet, 212a-2 Outlet, 213 Sealing section, 214 Back helium section, 22 Pressing section;

[0030] 3. Magnetofluid shaft, 31. Inner shaft, 31a. Accommodation space, 311. End component, 311a. First cooling channel, 312. Cylindrical component, 313. Sealing plate, 32. Outer shaft, 33. Magnetofluid, 34. Bearing, 35. Rotating plate;

[0031] 4 drive assembly, 41 stator, 42 mover, 43 mounting component, 431 first connecting part, 432 second connecting part, 433 second cooling channel;

[0032] 5 Lifting assembly, 51 Main body, 511 Cylinder, 511a Piston rod, 512 Lifting plate, 513 Bellows, 52 Lifting body, 53 Ejector pin;

[0033] 6. Rotary joints;

[0034] 7. Transition plate;

[0035] 8-axis rotation. Detailed Implementation

[0036] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] The term "several" as used in this article refers to a number of uncertain quantities, usually two or more; and when "several" is used to indicate the quantity of certain components, it does not indicate the quantitative relationship between these components.

[0038] The terms "first" and "second" used in this article are used only for the convenience of describing two or more structures or components that are identical or similar in structure and / or function, and do not indicate any special limitation on order and / or importance.

[0039] Magnetofluid, also known as magnetic liquid or ferrofluid, is a colloidal material composed of two phases: a solid phase, which mainly refers to magnetic solid nanoparticles, and a liquid phase, which refers to the liquid that can carry the solid magnetic nanoparticles. Magnetofluid has the fluidity, lubricity, and sealing properties of a liquid carrier, while also possessing the strong magnetism and other properties of solid nanoparticles.

[0040] Magnetofluid seals use permanent magnets to fix a magnetofluid between an inner and outer shaft. Because the gap between the inner and outer shafts is very small and the magnetic field strength is exceptionally high, it can withstand significant thrust along the axial direction, thus achieving a sealing effect. The inner shaft, outer shaft, and the magnetofluid positioned between them can be collectively referred to as a magnetofluid shaft.

[0041] Please refer to Figures 1-5 , Figure 1 This is a schematic diagram of a specific embodiment of the wafer stage device provided by the present invention. Figure 2 for Figure 1 Schematic diagram of the structure of the magnetohydrodynamic shaft. Figure 3 for Figure 1 A schematic diagram of the lifting assembly. Figure 4 for Figure 1 Schematic diagram of the central support platform. Figure 5 for Figure 1 A schematic diagram of the structure of the driving component.

[0042] like Figure 1As shown, the present invention provides a wafer stage device, including: a rotary stage assembly 2, including a support stage 21 and a pressing part 22, wherein the support stage 21 is used to support the wafer, and the pressing part 22... The pressing part 22 is used to press the wafer to ensure the reliability of wafer fixation. It can be an integral ring structure or include several parts distributed in the circumferential direction. The magnetic fluid shaft 3 includes an inner shaft 31 and an outer shaft 32. The inner shaft 31 and the outer shaft 32 can rotate relative to each other. A magnetic fluid 33 is provided between the inner shaft 31 and the outer shaft 32 to achieve a seal between the inner shaft 31 and the outer shaft 32. The inner shaft 31 includes an end part 311 and a cylindrical part 312, which together form a receiving space 31a. The lifting assembly 5 includes a main body 51 and a lifting body 52. ​​The main body 51 is located in the receiving space 31a. The lifting body 52 is slidably and sealed to the end part 311. The lifting body 52 interacts with the pressing part 22 to control the pressing part 22 to move relatively closer to or away from the support table 21. When the pressing part 22 is relatively away from the support table 21, it is convenient to place the wafer. When the pressing part 22 is relatively close to the support table 21, it can achieve the pressing and fixing of the wafer.

[0043] With the above scheme, the outer shaft 32 of the magnetohydrodynamic shaft 3 is barrel-shaped, and its interior can form a receiving space 31a. The main body 51 of the lifting assembly 5, which is used to drive the pressing part 22 to move relative to the support platform 21, is located in the receiving space 31a. In this way, the internal space of the inner shaft 31 can be utilized more fully to improve the structural compactness and integration of the equipment, and can effectively reduce the space occupied by the wafer stage device for easy installation.

[0044] Here, the embodiments of the present invention do not limit the specific structural form of the lifting component 5. In practical applications, those skilled in the art can make selections as needed. For example, the lifting component 5 can be a driving element that can directly output linear displacement, such as a cylinder or hydraulic cylinder. In this case, the aforementioned lifting body 52 can be the piston rod of these driving elements. Alternatively, the lifting component 5 can also be a driving element that can directly output rotational displacement, such as a motor. In this case, it is also necessary to use a displacement conversion mechanism in the form of a gear and rack mechanism or a lead screw mechanism to convert the directly output rotational displacement into the required linear displacement. Taking a gear and rack mechanism as an example, the aforementioned lifting body 52 can be a rack.

[0045] exist Figure 3In this embodiment, the lifting assembly 5 can use a standard cylinder. The main body 51 can include a cylinder 511 and a lifting plate 512. The cylinder 511 has a piston rod 511a, which can extend and retract, thereby driving the lifting plate 512 to rise and fall. The aforementioned lifting body 52 can be installed on the lifting plate 512. With this structure, the lifting plate 512 is equivalent to a transition connector, on which multiple lifting bodies 52 can be installed (two lifting bodies 52 are shown in the figure). Thus, multi-point drive can be achieved by one cylinder 511. On the one hand, the number of cylinders 511 used can be reduced to save costs and avoid the problem of inconsistent action caused by using multiple cylinders 511. On the other hand, multi-point drive is also more conducive to ensuring the stability of the lifting of the pressing part 22.

[0046] It should be noted that the solution of using the lifting plate 512 for transitional connection to enable one cylinder 511 to generate multiple driving points is only a preferred solution of the present invention, but it does not mean that only one cylinder 511 can be used in specific practice. In fact, the number of cylinders 511 can also be multiple in order to generate greater driving force.

[0047] Furthermore, the main body 51 may also include a bellows 513, the two ends of which can be connected to the lifting plate 512 and the end component 311 respectively. The bellows 513 can also be sleeved onto the lifting body 52 to achieve a sealed assembly between the lifting body 52 and the end component 311. Simultaneously, the bellows 513 has a certain elastic deformation capacity. When the cylinder 511 is inflated to drive the pressing part 22 upward, the bellows 513 can be compressed. When the cylinder 511 is deflated, the elastic force of the bellows 513 can be released to facilitate the rapid reset of the pressing part 22. Furthermore, the bellows 513 can also limit the stroke of the cylinder 511.

[0048] It is understandable that the sliding seal method is not limited to the bellows 513, but can also be achieved by setting annular seals such as sealing rings.

[0049] The pressing part 22 can clamp and fix the wafer by its own gravity or by the force of the lifting component 5, depending on the connection method between the lifting body 52 and the pressing part 22. When the lifting body 52 and the pressing part 22 are fixedly connected (the connection method is not limited), the pressing part 22 can clamp the wafer under the action of the lifting component 5. When the lifting body 52 and the pressing part 22 are only in contact, that is, when the lifting body 52 can only generate a lifting force on the pressing part 22 but not a pulling force, the pressing part 22 can clamp the wafer under its own gravity. Specifically, in this embodiment of the invention, the former solution is preferred to ensure the reliability of the wafer clamping and fixing.

[0050] In addition to driving the pressing part 22 to move, the lifting assembly 5 can also directly drive the wafer to move relative to the support stage 21 to facilitate wafer loading and unloading operations. Specifically, the lifting assembly 5 may also include a ejector pin 53, which is slidably and sealingly fitted to the end component 311 for interacting with the wafer.

[0051] Combination Figure 3 The ejector pin 53 can also be mounted on the lifting plate 512, and the axial dimension of the ejector pin 53 should be smaller than that of the lifting body 52. ​​In this way, the support height of the lifting body 52 is higher than that of the ejector pin 53. When the lifting plate 512 drives the lifting body 52 and the ejector pin 53 to lift, the lifting body 52 can first move the pressing part 22 away from the support table 21, and then the ejector pin 53 will start to contact the wafer and drive the wafer away from the support table 21. When the lifting plate 512 drives the lifting body 52 and the ejector pin 53 to descend, the lifting body 52 can first make the wafer stably placed on the support table 21, and then the pressing part 22 will press against the wafer. This arrangement can better avoid interference problems between the wafer and the pressing part 22 during the operation.

[0052] The sealing connection between the ejector pin 53 and the end component 311 can be found in the aforementioned description of the sealing connection between the lifting body 52 and the end component 311. In fact, in the appendix... Figure 3 In the scheme shown, a lifting body 52 and a pin 53 can be sealed and assembled using the same bellows 513, which can reduce the number of bellows 513 used.

[0053] Please continue to refer to this. Figure 1 The wafer stage device provided by the present invention may further include: a housing assembly 1, the internal space of which can be connected to the atmospheric environment, the housing assembly 1 may include a support plate 11, the outer shaft 32 may be sealed and installed on the support plate 11 (the specific sealing method is not limited, for example, a sealing ring, a sealing gasket, etc. may be set), the accommodating space 31a of the inner shaft 31 may be connected to the internal space of the housing assembly 1, that is, the accommodating space 31a is also in the atmospheric environment; and a driving assembly 4, which may be located inside the housing assembly 1 and may be connected to the inner shaft 31 for transmission, and is used to drive the support stage 21 to rotate through the inner shaft 31 to meet the motion form required for wafer processing.

[0054] With this approach, the housing assembly 1 can isolate the external vacuum environment (the environment during wafer processing) from the internal atmospheric environment. The drive assembly 4 is assembled entirely within the housing assembly 1. Thus, the drive assembly 4 does not require specialized vacuum components; conventional components are sufficient, resulting in lower costs and easier assembly and maintenance. The magnetofluid shaft 3 includes an inner shaft 31 and an outer shaft 32 sealed by a magnetofluid 33. When the outer shaft 32 is sealed and assembled with the support plate 11, the accommodating space 31a can also be isolated from the external vacuum environment. At the same time, the accommodating space 31a is also connected to the atmospheric environment. Therefore, the accommodating space 31a is also in the atmospheric environment. Thus, all components assembled within the accommodating space 31a (such as the aforementioned main body 51) do not require specialized vacuum components; conventional components are sufficient, further reducing costs and improving the ease of assembly and maintenance.

[0055] Here, the embodiments of the present invention do not limit the specific structural form of the housing component 1, as long as it can achieve the technical effect of accommodating the drive component 4.

[0056] Combination Figure 1 The housing assembly 1 is also connected to a revolution shaft 8, which is also connected to a drive element (not shown in the figure). Under the action of the drive element, the housing assembly 1, together with the magnetohydrodynamic shaft 3 and the rotary table assembly 2, can rotate as a whole to adjust the angle of the support platform 21. The drive assembly 4 is used to realize the rotation of the support platform 21. The revolution shaft 8 can be a hollow cylindrical part to connect the internal space of the housing assembly 1 with the external environment.

[0057] The drive assembly 4 may specifically be a motor, including a stator 41, a mover 42, and a mounting component 43. The mover 42 can be connected to the inner shaft 31 for transmission. The mounting component 43 is used to install the drive assembly 4, and a second cooling channel 433 is provided in the mounting component 43 for cooling and temperature control of the motor to ensure the working performance of the motor.

[0058] The connection between the mover 42 and the inner shaft 31 can be varied, as long as the reliability of power transmission can be guaranteed. For example, a pulley, sprocket, gear, or other transmission connection can be used to adjust the transmission ratio. In the embodiment shown in the attached drawings, as... Figure 1 , Figure 2 and Figure 5 As shown, the mover 42 can be connected to the inner shaft 31 via the rotating plate 35 to accommodate the installation positions of the mover 42 and the inner shaft 31; it is understood that if the installation position allows, the mover 42 can also be directly connected to the inner shaft 31.

[0059] Similarly, the structural form of the mounting component 43 can be varied, as long as the installation reliability of the mounting component 43 can be guaranteed. In the embodiment shown in the accompanying drawings, such as... Figure 5 As shown, the mounting component 43 may include a first connecting part 431 and a second connecting part 432. The first connecting part 431 may be connected to the outer shaft 32; the second connecting part 432 may be connected to the first connecting part 431. Specific connection methods include, but are not limited to, threaded connection, screw connection, interference fit, snap-fit, welding, etc.; the second cooling channel 433 may be formed between the first connecting part 431 and the second connecting part 432. Specifically, it may be formed by setting a groove on the mating surfaces of the first connecting part 431 and / or the second connecting part 432; sealing components in the form of sealing rings, sealing fillers, etc., may be provided on both axial sides of the second cooling channel 433 to ensure sealing performance.

[0060] In this way, the drive component 4 is integrated and assembled on the outer shaft 32, which in turn is assembled on the support plate 11. This means that the entire device is integrated and assembled on the support plate 11, resulting in a highly compact structure that helps reduce the size. Furthermore, the second cooling channel 433 can also improve the cooling performance of the motor, enabling control of the motor's operating temperature under long-term working conditions, thus ensuring the motor's working stability and efficiency.

[0061] In fact, the mounting component 43 is not limited to being connected to the outer shaft 32; it can also be directly fixed to the support plate 11, thus achieving the installation and fixation of the drive component 4.

[0062] Furthermore, the type of cooling medium introduced into the second cooling channel 433 is not limited here. In practice, those skilled in the art can configure it according to actual needs, as long as it meets the requirements of use. For example, the cooling medium can be a gaseous cooling medium, such as cooling air; or, the cooling medium can be a liquid cooling medium, such as cooling water.

[0063] In further detail, the first connecting part 431 may be provided with a first stop, and the second connecting part 432 may be provided with a second stop. The stator 41 can be axially fixedly assembled through the first stop and the second stop.

[0064] As described in the background section, common wafer fabrication processes include ion beam etching and ion beam deposition, which have different requirements for ambient temperature. Generally, ion beam etching requires a cooling environment, while ion beam deposition requires a thermal environment.

[0065] Based on this, the support stage 21 provided in this embodiment of the invention may include a hot stage 211 and a cold stage 212. The hot stage 211 can be heated to provide the thermal environment required for ion beam deposition, and the cold stage 212 can be cooled to provide the cold environment required for ion beam etching. Thus, the wafer stage device provided in this embodiment of the invention is compatible with both ion beam etching and ion beam deposition wafer processing technologies.

[0066] Here, the embodiments of the present invention do not limit the heating method of the hot platform 211 and the cooling method of the cold platform 212, as long as the corresponding functions can be met.

[0067] The hot stage 211 can be heated by electric heating, such as by embedding heating wires. The cold stage 212 can be cooled by convection heat exchange; this embodiment can be referred to Figure 4. The side of the cold stage 212 facing the hot stage 211 can be provided with a third cooling channel 212a. The support platform 21 can also include a sealing part 213, which can be disposed between the cold stage 212 and the hot stage 211 to ensure the sealing performance of the third cooling channel 212a. The cold stage 212 can be provided with an inlet 212a-1 and an outlet 212a-2 connected to the third cooling channel 212a to realize the circulation of the cooling medium. The type of cooling medium can also include gaseous cooling medium and liquid cooling medium.

[0068] In some alternative embodiments, the support stage 21 may also include a helium back section 214, which may be located on the side of the hot stage 211 away from the cold stage 212, i.e., the side closer to the wafer, for timely introduction of helium gas during wafer processing to meet the requirements of wafer processing.

[0069] As mentioned earlier, ion beam deposition requires a relatively high ambient temperature, typically above 120°C. However, the operating temperature of the magnetofluid shaft 3 is only between -40°C and 120°C. When the temperature exceeds 120°C, the sealing performance of the magnetofluid 33 will be affected, and the bearing 34 of the magnetofluid shaft 3 will overheat. This will impact the lifespan and operating condition of the bearing 34, leading to unstable rotation of the magnetofluid shaft 3 and severely affecting its normal operation.

[0070] Therefore, in this embodiment of the invention, a first cooling channel 311a can be provided in the end component 311 for controlling the temperature of the magnetohydrodynamic shaft 3. The first cooling channel 311a can be formed by providing a groove on the side of the end component 311 facing the support platform 21, and then covering it with a sealing plate 313 (the fixing method of the sealing plate 313 includes, but is not limited to, welding, screw connection, riveting, etc.) to seal the groove opening.

[0071] It should be noted that the first cooling channel 311a is not limited to being located on the end component 311; it can also be located on the cylindrical component 312, and similarly, it can also be located on the outer shaft 32. These are all feasible solutions in practice.

[0072] Furthermore, the wafer stage device provided by the present invention may also include a rotary joint 6 and a transition plate 7. Both the rotary joint 6 and the transition plate 7 can be located inside the cylindrical member 312, that is, both can be located in the aforementioned receiving space 31a, so as to fully utilize the internal space of the inner shaft 31. The rotary joint 6 can be connected to the end member 311 through the transition plate 7. With this structure, the installation position of the rotary joint 6 can be adjusted by setting the transition plate 7; moreover, it can also solve the problem of interface mismatch when the rotary joint 6 is directly connected to the end member 311. That is to say, the two axial ends of the transition plate 7 can have two types of interfaces, one type of interface can be used to connect to the end member 311, and the other type of interface can be used to connect to the rotary joint 6.

[0073] It is understandable that the aforementioned transition plate 7 may not actually exist. In this case, the rotary joint 6 can be directly connected to the end component 311, which does not affect the rotary joint 6 from transmitting rotational driving force to the inner shaft 31.

[0074] The aforementioned rotary joint 6 is a gas, electricity, and liquid hybrid joint, and its interior can accommodate helium gas pipes, coolant pipes, conductive wires, signal wires, etc.

[0075] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A wafer stage device, characterized in that, include: The rotary table assembly (2) includes a support platform (21) and a pressing part (22), wherein the support platform (21) is used to support the wafer and the pressing part (22) is used to press the wafer; The magnetohydrodynamic shaft (3) includes an inner shaft (31) and an outer shaft (32), and a magnetohydrodynamic fluid (33) is disposed between the inner shaft (31) and the outer shaft (32). The inner shaft (31) includes an end member (311) and a cylindrical member (312), which together form a receiving space (31a). The lifting assembly (5) includes a main body (51) and a lifting body (52). The main body (51) is located in the receiving space (31a). The lifting body (52) is slidably and sealingly fitted to the end component (311). The lifting body (52) interacts with the pressing part (22). The housing assembly (1) has an internal space that is connected to the atmospheric environment. The housing assembly (1) includes a support plate (11), and the outer shaft (32) is sealed and assembled on the support plate (11). The accommodating space (31a) is connected to the internal space of the housing assembly (1).

2. The wafer stage apparatus according to claim 1, characterized in that, The main body (51) includes a cylinder (511) and a lifting plate (512). The cylinder (511) has a piston rod (511a) connected to the lifting plate (512). The lifting plate (512) is connected to a plurality of lifting bodies (52).

3. The wafer stage apparatus according to claim 2, characterized in that, The main body (51) also includes a corrugated pipe (513), the two ends of which are connected to the lifting plate (512) and the end component (311) respectively, and the corrugated pipe (513) is sleeved on the lifting body (52).

4. The wafer stage apparatus according to claim 1, characterized in that, The lifting assembly (5) also includes a push pin (53), which is slidably and sealingly fitted to the end component (311).

5. The wafer stage apparatus according to claim 4, characterized in that, One of the lifting bodies (52) and one of the ejector pins (53) share a bellows (513) for sealed assembly.

6. The wafer stage apparatus according to claim 1, characterized in that, The magnetohydrodynamic shaft (3) is provided with a first cooling channel (311a).

7. The wafer stage apparatus according to any one of claims 1-6, characterized in that, Also includes: A drive assembly (4), at least partially located within the housing assembly (1), and the drive assembly (4) is drive-connected to the inner shaft (31).

8. The wafer stage apparatus according to claim 7, characterized in that, The drive assembly (4) includes a stator (41), a mover (42) and a mounting member (43). The mover (42) is connected to the inner shaft (31) for transmission. The mounting member (43) is used to install the drive assembly (4) and is provided with a second cooling channel (433).

9. The wafer stage apparatus according to claim 8, characterized in that, The mounting component (43) includes a first connecting part (431) and a second connecting part (432) connected together. The first connecting part (431) is connected to the outer shaft (32), and the second cooling channel (433) is formed between the first connecting part (431) and the second connecting part (432).

10. The wafer stage apparatus according to claim 9, characterized in that, The first connecting part (431) is provided with a first stop, and the second connecting part (432) is provided with a second stop. The stator (41) is positioned and assembled by the first stop and the second stop.

11. The wafer stage apparatus according to any one of claims 1-6, characterized in that, The support platform (21) includes a hot platform section (211) and a cold platform section (212).

12. The wafer stage apparatus according to claim 11, characterized in that, The cold stage section (212) is provided with a third cooling channel (212a) on the side facing the hot stage section (211). It also includes a sealing part (213) disposed between the cold table part (212) and the hot table part (211).

13. The wafer stage apparatus according to claim 11, characterized in that, It also includes a back helium section (214), which is located on the side of the support platform (21) near the wafer.

14. The wafer stage apparatus according to any one of claims 1-6, characterized in that, It also includes a rotary joint (6) which is connected to the end component (311).

15. The wafer stage apparatus according to claim 14, characterized in that, It also includes a transition plate (7), through which the rotary joint (6) is connected to the end component (311).

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