Magnetic suspension porous rotor and magnetic suspension turntable
By designing uniformly arranged through holes and arc-shaped connecting walls on the annular support wall of the magnetic levitation rotor, the problems of uneven wafer temperature and insufficient structural strength are solved, achieving better temperature uniformity and strength improvement, which is suitable for magnetic levitation rotors in semiconductor manufacturing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUZHOU SUPERMAG INTELLIGENT TECH CO LTD
- Filing Date
- 2025-07-11
- Publication Date
- 2026-06-26
Smart Images
Figure CN224418703U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of magnetic levitation technology, specifically a magnetic levitation porous rotor and a magnetic levitation turntable. Background Technology
[0002] In semiconductor manufacturing, wafer cleanliness is crucial because it affects the yield of subsequent semiconductor processes and products. To achieve ultra-cleanliness, silicon or other semiconductor wafers must be processed in a controlled, ultra-clean atmosphere. For example, in wafer manufacturing, one step is annealing the wafer after ion implantation doping. Doping applies strain to the crystal structure, and if the stress is not released quickly, it will cause undesirable changes in the resistivity of the ion-doped material. Currently, rapid thermal processing (RT) is commonly used for annealing. Furthermore, wafer processing uniformity is critical. To achieve uniformity, the wafer is typically rotated around its center vertical axis or z-axis during processing. Rotation is also used in other wafer processing steps, such as chemical vapor deposition, thermal processing, ion implantation doping, and other doping techniques. To meet the stringent requirements of ultra-cleanliness and processing uniformity in semiconductor manufacturing, semiconductor thermal processing equipment ideally employs a non-contact, rotary-driven magnetic levitation turntable.
[0003] For example, a magnetic levitation turntable includes a magnetic levitation rotor and a magnetic levitation stator. The magnetic levitation stator generates a magnetic field to drive the magnetic levitation rotor and its carrier to rotate and levitate. The magnetic levitation stator includes a levitation control assembly for applying an actively controlled levitation force to the magnetic levitation rotor to achieve axial active control and / or radial active control. The levitation control assembly includes multiple stator magnetic poles evenly distributed in the circumferential direction, and electromagnetic windings for levitation control are disposed on the stator magnetic poles. The magnetic levitation stator may also include a permanent magnet device that provides a permanent magnet bias magnetic field (magnetic flux), which can be a toroidal permanent magnet or multiple discrete permanent magnets.
[0004] The process chamber of a rapid thermal processing equipment is a vacuum chamber, comprising an inner ring (inner chamber wall), an outer ring (outer chamber wall), and a connecting plate (chamber bottom) connecting the bottoms of the inner and outer rings. A U-shaped annular space is formed between the inner and outer rings to house the magnetically levitated rotor. The outer ring has a thin wall to isolate the magnetically levitated stator and rotor. In the rapid thermal processing chamber, the magnetically levitated rotor typically supports the wafer via multiple pillars, with heat conduction between the pillars and the wafer. On one hand, the rotation of these pillars disturbs the airflow within the chamber; on the other hand, the pillars carry away heat from the outer surface of the wafer through heat conduction. Thus, as the pillars move closer to or further away from the pyrometer during rotation, the heat conducted by the pillars affects the pyrometer's measurement results, causing significant fluctuations in the measured temperature and consequently, uneven surface temperature of the wafer. To address these issues, some technical solutions employ annular support walls with through-holes instead of pillars to support the wafer. This increases the wind resistance area of the magnetic levitation rotor, thereby improving wind resistance pressure and preventing disturbances to the gas within the process chamber during rotor rotation. This ensures stable heat conduction between the wafer and the rotor, reducing the difference in temperature change rates at different locations on the wafer and improving temperature uniformity on the wafer surface. However, to achieve maximum weight reduction, this structure arranges multiple through-holes in a single layer. The through-holes are relatively large, requiring further improvement in temperature distribution uniformity. Furthermore, the connecting walls between adjacent through-holes exhibit weak support strength. Summary of the Invention
[0005] In order to overcome the defects in the prior art, this utility model provides a magnetic levitation porous rotor and a magnetic levitation turntable, which are used to solve at least one of the above problems.
[0006] This disclosure provides a magnetically levitated porous rotor, comprising an annular rotor body, an annular support wall formed at one end of the annular rotor body, and at least one annular flange extending radially outward from the annular rotor body. The annular support wall has at least two sets of through holes arranged axially, each set of through holes including multiple through holes that are radially connected and have the same axial height, and the multiple through holes are evenly spaced circumferentially.
[0007] Furthermore, the annular support wall has two or three sets of through holes arranged along the axial direction.
[0008] Furthermore, each through hole in each group is located between two adjacent through holes in an adjacent group; or, each through hole in each group is axially opposite to one through hole in an adjacent group.
[0009] Furthermore, all through holes in the at least two sets of through holes have the same shape and size.
[0010] Furthermore, the through hole is generally circular, triangular, rectangular with corners removed, or square with corners removed.
[0011] Furthermore, the sum of the areas of all the through holes in the at least two sets of through holes is greater than or equal to half of the side surface area of the annular support wall.
[0012] Furthermore, the radial cross-section of the connecting wall between two adjacent through holes in each group of through holes is arc-shaped or wavy.
[0013] Furthermore, the number of the at least one annular flange is two or three, one of the annular flanges is located at the position where the annular support wall is connected to the annular rotor body, and a plurality of rotor teeth are formed on the annular flange, the plurality of rotor teeth being evenly spaced along the circumference; a tooling hole is formed on a portion of the plurality of rotor teeth.
[0014] Furthermore, the circumferential length of the rotor teeth is the same as the distance between two adjacent rotor teeth.
[0015] Furthermore, it also includes a limiting ring and an annular support platform, wherein the limiting ring and the annular support platform are located at one end of the annular support wall away from the annular rotor body.
[0016] Furthermore, the radial dimension of the inner wall of the limiting ring is larger than the radial dimension of the inner wall of the annular support wall, and the annular support platform is connected between the inner wall of the limiting ring and the inner wall of the annular support wall. Alternatively, the inner wall of the limiting ring is flush with the inner wall of the annular support wall, and the annular support platform is disposed on the inner wall at the junction of the limiting ring and the annular support wall.
[0017] Furthermore, an annular limiting groove is formed on the inner wall of the limiting ring.
[0018] Furthermore, the wall thickness of the annular support wall is less than the wall thickness of the rotor body, and the inner wall of the annular support wall is flush with the inner wall of the rotor body, or one end of the annular support wall is located at the middle of one end of the rotor body.
[0019] This disclosure also provides a magnetic levitation turntable, including the aforementioned magnetic levitation porous rotor and a magnetic levitation stator, wherein the magnetic levitation stator is configured to drive the magnetic levitation porous rotor to rotate and levitate in a non-contact manner.
[0020] The beneficial effects of this utility model are as follows:
[0021] This invention proposes a magnetically levitated porous rotor, comprising an annular rotor body, an annular support wall formed at one end of the annular rotor body, and at least one annular flange extending radially outward from the annular rotor body. The annular support wall has at least two sets of through holes arranged axially. Each set of through holes includes multiple through holes that are radially connected and have the same axial height, and these multiple through holes are evenly spaced circumferentially. Given a uniform total area of through holes formed on the annular support wall, setting one layer of through holes results in relatively larger through hole sizes, while setting two or more layers results in relatively smaller through hole sizes. The alternating distribution of through holes and connecting walls is more uniform throughout the circumference, thus improving the uniformity of temperature distribution and overall structural strength.
[0022] To make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a schematic diagram of the structure of an embodiment of the magnetically levitated porous rotor of this utility model. Figure 1 ;
[0025] Figure 2 This is a schematic diagram of the structure of an embodiment of the magnetically levitated porous rotor of this utility model. Figure 2 ;
[0026] Figure 3 yes Figure 2 Cross-sectional view along the AA direction;
[0027] Figure 4 yes Figure 3 Enlarged structural diagram at point A in the middle;
[0028] Figure 5 This is a schematic diagram of another embodiment of the magnetically levitated porous rotor in this utility model. Figure 1 ;
[0029] Figure 6 This is a schematic diagram of another embodiment of the magnetically levitated porous rotor in this utility model. Figure 2 ;
[0030] Figure 7 This is a schematic diagram of a modified example of the connecting wall in this utility model;
[0031] Figure 8 This is a schematic diagram of the structure of an embodiment of the magnetic levitation turntable in this utility model. Detailed Implementation
[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0033] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. The terms "comprising" and "equipped with," and any variations thereof, in the specification, claims, and the aforementioned drawings of this utility model are intended to cover non-exclusive inclusion. For example, a system, product, or device that includes a series of units is not necessarily limited to those units explicitly listed, but may include other units not explicitly listed or inherent to such products or devices.
[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.
[0035] The accompanying drawings in this disclosure are not drawn to scale, and the specific dimensions and quantity of each structure can be determined according to actual needs. The drawings described in this disclosure are only schematic diagrams.
[0036] Figure 1 This is a schematic diagram of the structure of one embodiment of the magnetically levitated porous rotor in this utility model. Figure 1 ; Figure 2 This is a schematic diagram of the structure of one embodiment of the magnetically levitated porous rotor in this utility model. Figure 2 ; Figure 3 yes Figure 2 Cross-sectional view along the AA direction; Figure 4 yes Figure 3 Enlarged structural diagram at point A in the middle; Figure 5This is a schematic diagram of another embodiment of the magnetically levitated porous rotor in this utility model. Figure 1 ; Figure 6 This is a schematic diagram of another embodiment of the magnetically levitated porous rotor in this utility model. Figure 2 ; Figure 7 This is a schematic diagram of a modified example of the connecting wall in this utility model; Figure 8 This is a schematic diagram of the structure of an embodiment of the magnetic levitation turntable in this utility model.
[0037] See Figure 1 , Figure 2 , Figure 3 , Figure 4 According to an embodiment of this utility model, a magnetically levitated porous rotor 1 is proposed, comprising an annular rotor body 11, an annular support wall 12 formed at one end of the annular rotor body 11, and at least one annular flange 13 extending radially outward along the annular rotor body 11. The annular support wall 12 has at least two sets of through holes 121 arranged axially. Each set of through holes 121 includes multiple through holes 121 that are radially penetrating and have the same axial height. The multiple through holes are evenly spaced circumferentially. Based on the same principle, this utility model's magnetically levitated porous rotor uses an annular support wall with at least two sets of through holes instead of a column to support the wafer. This increases the wind resistance area of the magnetically levitated rotor, thereby increasing the wind resistance pressure and preventing disturbance to the gas in the process chamber during rotation. This ensures stable heat conduction between the wafer and the magnetically levitated rotor, thereby reducing the difference in temperature change rates at different locations on the wafer and improving the temperature uniformity of the wafer surface. Moreover, under the condition that the total area of the through holes formed on the annular support wall is the same, setting one layer of through holes results in a relatively large through hole size, while setting two or more layers of through holes results in a relatively small through hole size. This makes the alternation of through holes and connecting walls more uniformly distributed throughout the circumference. Therefore, it is more conducive to the uniformity of temperature distribution and also to the overall structural strength.
[0038] According to embodiments of this disclosure, see Figure 1 and Figure 3 Two sets of through holes 121 are formed on the annular support wall 12, arranged axially. Compared to a single set of through holes, the size of the two sets of through holes is significantly reduced, but the connecting wall 122 between the through holes remains unchanged. This improves the uniformity of temperature distribution while ensuring the overall structural strength. The two sets of through holes can be arranged axially aligned or intersecting. See also... Figure 1 and Figure 3Each through-hole in each group is located between two adjacent through-holes in the adjacent group; that is, the two groups of through-holes are arranged in a staggered pattern. This staggered arrangement of the upper and lower through-holes allows for a greater number of through-holes within a limited area while reducing weight and maintaining overall structural strength. Furthermore, this design indirectly increases the heat transfer distance from one end of the connecting wall to the other, which can help reduce the heat transfer temperature. See also... Figure 5 and Figure 6 Each through hole in each group is axially aligned with one through hole in the adjacent group, meaning the two groups of through holes can be arranged in an axially aligned manner. In other embodiments, three or more groups of through holes 121 arranged axially can also be formed on the annular support wall 12.
[0039] According to embodiments of this disclosure, see Figure 1 and Figure 3 All through holes in at least two sets of through holes 121 have the same shape and size. This facilitates production and manufacturing, but is not limited to this. In other embodiments, taking two sets of through holes as an example, the size or shape of the upper through hole and the lower through hole may not be the same. The shape of the through holes in the above embodiments is not limited. Preferably, the shape of the through hole 121 is approximately circular, triangular, rectangular with corners removed, or square with corners removed.
[0040] According to embodiments of this disclosure, see Figure 1 and Figure 3 The through holes serve two purposes: reducing the weight of the magnetic levitation rotor and connecting the inside and outside of the annular support wall. The proportion of the total area of all through holes to the side surface area of the annular support wall depends on the weight reduction target and the balance of the overall strength of the annular support wall. Preferably, the sum of the areas of all through holes in at least two sets is greater than or equal to half of the side surface area of the annular support wall.
[0041] According to embodiments of this disclosure, see Figure 7 In each group of vias, the radial cross-section of the connecting wall 122 between two adjacent vias is arc-shaped or wavy. The annular support wall supports the wafer, and heat conduction also occurs between the annular support wall and the wafer. Designing the connecting wall between adjacent vias as arc-shaped or wavy can increase the heat transfer distance and reduce the heat transfer temperature.
[0042] According to embodiments of this disclosure, see Figure 1 , Figure 3 , Figure 5 and Figure 6The magnetic levitation rotor has at least two annular flanges 13, one of which is located at the connection between the annular support wall 12 and the annular rotor body 11. This annular flange 13 has multiple rotor teeth 131 formed on it, which are evenly spaced circumferentially. A portion of the rotor teeth 131 has a tooling hole 132 formed on it. In other embodiments, the magnetic levitation rotor has three annular flanges 13, which are spaced axially. The number of annular flanges depends on the structure of the magnetic levitation stator. Similarly, the position of the annular flange with rotor teeth also depends on the position of the rotation control winding of the magnetic levitation stator. The rotor teeth 131 are mainly used to cooperate with the rotation control winding to achieve rotor rotation control. In a preferred embodiment, see [reference needed]. Figure 2 The rotor teeth 131 have eight teeth, but are not limited to this. In other embodiments, the rotor teeth may be configured to have more or fewer teeth depending on the structural features of the rotation control winding.
[0043] According to embodiments of this disclosure, see Figure 1 and Figure 2 The circumferential length (tooth width) of the rotor teeth is the same as the distance (tooth pitch) between two adjacent rotor teeth 131. However, this is not the limitation; in other embodiments, the circumferential length of the rotor teeth may be greater than or less than the distance between two adjacent rotor teeth 131. The width and tooth pitch of the rotor teeth have a significant impact on the performance of the motor. These parameters typically need to be optimized based on specific application requirements and motor design goals. For example, wider rotor teeth can increase the local magnetic field strength, but excessive width may lead to magnetic field non-uniformity, affecting motor efficiency. Appropriate tooth pitch helps reduce magnetic flux saturation and improve the uniformity of the magnetic field distribution.
[0044] According to embodiments of this disclosure, see Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 The magnetic levitation rotor 1 also includes a limiting ring 14 and an annular support platform 15, which are located at the end of the annular support wall 12 away from the annular rotor body 11. The annular support platform is used for the wafer and its carrier ring. The limiting ring is used to define the circumference of the carrier ring.
[0045] According to embodiments of this disclosure, see Figure 4The inner wall of the limiting ring 14 is flush with the inner wall of the annular support wall 12, and the annular support platform 15 is disposed on the inner wall at the junction of the limiting ring 14 and the annular support wall 12. In other embodiments, the radial dimension of the inner wall of the limiting ring 14 may be larger than the radial dimension of the inner wall of the annular support wall 12, and the annular support platform 12 connects the inner wall of the limiting ring 14 and the inner wall of the annular support wall 12. When the radial dimension of the annular support wall is the same, different connection structures can correspond to carrier rings and wafers with different radial dimensions. Preferably, an annular limiting groove 141 is formed on the inner wall of the limiting ring 14. The annular limiting groove is used to accommodate the positioning elastic ring to achieve better positioning of the carrier ring and the wafer on it, ensuring that there is no hard contact between the carrier ring and the limiting ring.
[0046] According to embodiments of this disclosure, see Figure 3 and Figure 6 The wall thickness of the annular support wall 12 is less than the wall thickness of the rotor body 11. The inner wall of the annular support wall 12 is flush with the inner wall of the rotor body 11, or one end of the annular support wall 12 is located at the middle of one end of the rotor body 11. Similarly, depending on the position of the annular support wall at one end of the rotor body, different radial dimensions of carrier rings and wafers can be accommodated. The fact that the wall thickness of the annular support wall is less than the wall thickness of the rotor body (the thickness in the radial direction of the rotor) reduces the weight of the annular support wall, achieving a weight similar to that of the column, thereby improving the versatility of the rotor.
[0047] Based on the same inventive concept, see [link to inventive concept] Figure 8 This invention also proposes a magnetic levitation turntable, including the magnetic levitation porous rotor 1 in the above embodiments. The magnetic levitation turntable also includes a magnetic levitation stator 2, which is configured to drive the magnetic levitation porous rotor 1 to rotate and levitate in a non-contact manner.
[0048] According to embodiments of this disclosure, see Figure 6 The magnetically levitated stator 2 includes a permanent magnet device 21 and two layers of levitation control components 22. The levitation control components are configured to apply an actively controlled levitation force to the magnetically levitated porous rotor 1. The permanent magnet device 21 is configured to apply a permanent magnet bias magnetic field to the magnetically levitated porous rotor 1. The permanent magnet device may include multiple permanent magnet components, which are uniformly arranged in the circumferential direction. The position of each permanent magnet component is defined as the configuration orientation. The line connecting the center of each configuration orientation in the radial plane and the projection point of the rotation axis of the magnetically levitated porous rotor in the radial plane is defined as the radial line. Each permanent magnet component includes multiple permanent magnets, which are arranged at intervals in the same radial plane with the radial line as the axis of symmetry. The magnetic flux generated by the permanent magnets is applied to the magnetically levitated porous rotor through the stator magnetic poles of the levitation control components.
[0049] The suspension control component 22 is configured to apply an actively controlled suspension force to the magnetically levitated porous rotor 1. This suspension control component can be configured as a radial suspension control component or an axial suspension control component. In a specific magnetically levitated turntable, different suspension control components can be assembled according to the needs of radial and axial suspension control. The axial suspension control component is mainly used for the active control of the rotor's axial direction to control the rotor's axial suspension height. The radial suspension control component is mainly used for the active control of the rotor's radial direction to achieve stable radial suspension of the rotor.
[0050] This utility model uses specific embodiments to illustrate the principle and implementation of the utility model. The above description of the embodiments is only for the purpose of helping to understand the technical solution and core idea of the utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of the utility model. Therefore, the content of this specification should not be construed as a limitation of the utility model.
Claims
1. A magnetically levitated porous rotor, comprising an annular rotor body (11), an annular support wall (12) formed at one end of the annular rotor body, and at least one annular flange (13) extending radially outward along the annular rotor body, characterized in that, The annular support wall has at least two sets of through holes (121) arranged along the axial direction. Each set of through holes includes multiple through holes that are radially connected and have the same axial height. The multiple through holes are evenly spaced along the circumferential direction.
2. The magnetically levitated porous rotor according to claim 1, characterized in that, The annular support wall has two or three sets of through holes arranged along the axial direction.
3. The magnetically levitated porous rotor according to claim 2, characterized in that, Each through hole in each group is located between two adjacent through holes in an adjacent group; or, each through hole in each group is axially opposite to one through hole in an adjacent group.
4. The magnetically levitated porous rotor according to claim 1, characterized in that, All through holes in the at least two sets of through holes have the same shape and size.
5. The magnetically levitated porous rotor according to claim 4, characterized in that, The through hole is roughly circular, triangular, rectangular with corners removed, or square with corners removed.
6. The magnetically levitated porous rotor according to claim 1, characterized in that, The sum of the areas of all the through holes in the at least two sets of through holes is greater than or equal to half of the side surface area of the annular support wall.
7. The magnetically levitated porous rotor according to claim 2, characterized in that, The radial cross-section of the connecting wall (122) between two adjacent through holes in each group is arc-shaped or wavy.
8. The magnetically levitated porous rotor according to claim 1, characterized in that, The number of the at least one annular flange is two or three, one of the annular flanges is located at the position where the annular support wall is connected to the annular rotor body, and a plurality of rotor teeth (131) are formed on the annular flange, and the plurality of rotor teeth are evenly spaced along the circumference; a tooling hole (132) is formed on a portion of the plurality of rotor teeth.
9. The magnetically levitated porous rotor according to claim 8, characterized in that, The circumferential length of the rotor teeth is the same as the distance between two adjacent rotor teeth.
10. The magnetically levitated porous rotor according to claim 1, characterized in that, It also includes a limiting ring (14) and an annular support platform (15), wherein the limiting ring and the annular support platform are located at one end of the annular support wall away from the annular rotor body.
11. The magnetically levitated porous rotor according to claim 10, characterized in that, The radial dimension of the inner wall of the limiting ring is greater than the radial dimension of the inner wall of the annular support wall, and the annular support platform is connected between the inner wall of the limiting ring and the inner wall of the annular support wall; or, the inner wall of the limiting ring is flush with the inner wall of the annular support wall, and the annular support platform is disposed on the inner wall at the junction of the limiting ring and the annular support wall.
12. The magnetically levitated porous rotor according to claim 10, characterized in that, An annular limiting groove (141) is formed on the inner wall of the limiting ring.
13. The magnetically levitated porous rotor according to claim 1, characterized in that, The thickness of the annular support wall is less than the thickness of the rotor body, and the inner wall of the annular support wall is flush with the inner wall of the rotor body or one end of the annular support wall is located at the middle of one end of the rotor body.
14. A magnetically levitated turntable, characterized in that, The device includes a magnetically levitated porous rotor (1) according to any one of claims 1-13, and also includes a magnetically levitated stator (2) configured to drive the magnetically levitated porous rotor to rotate and levitate in a non-contact manner.