Cooling structure, rotating magnet and physical vapor deposition equipment

Abstract

The invention belongs to the technical field of vacuum deposition, and provides a cooling structure, a rotating magnet and physical vapor deposition equipment, the cooling structure comprises at least one inlet, a cavity, at least one outlet and a coolant, the cavity surrounds one end of a rotating shaft of the rotating magnet; the inlet is formed in the cavity; the outlet is formed in the other end of the rotating shaft; and the coolant enters from the inlet of the cavity, moves from the periphery in the cavity to the center of the rotating shaft, and flows out from the outlet. According to the cooling structure, cooling from the periphery to the center is carried out, and the cooling efficiency and the cooling uniformity of the rotating magnet assembly which generates high heat in the sputtering process can be improved.

Description

Technical Field

[0001] This invention belongs to the field of vacuum deposition technology and relates to cooling structures, rotating magnets, and physical vapor deposition equipment. Background Technology

[0002] In the PVD process, a plasma is formed in a chamber by a rotating magnet under the condition of applying a direct current (DC) power supply. Inert gas ions bombard the target source to cause sputtering, thereby depositing a thin film on the wafer.

[0003] During this process, the rotating magnet generates high-temperature heat, which causes thermal deformation (bending, deformation, breakage, etc.) of the magnet structure. Furthermore, the continuous rise in magnet temperature will eventually affect the temperature of the target source, leading to serious problems such as a decrease in the quality of the deposited film and a deterioration in process uniformity.

[0004] The existing technology employs a water-cooled cooling structure that forms a cooling water flow path from the center to the periphery inside the rotating magnet assembly and circulates the cooling water.

[0005] The above-mentioned water-cooled cooling structure has the following technical problems: First, the limitations and unevenness of cooling efficiency: Unidirectional flow from the center to the periphery makes it difficult to achieve optimal heat exchange efficiency across the entire magnet range. In particular, for specific areas where heat is concentrated, cooling may be insufficient, making it difficult to achieve uniform cooling.

[0006] Second, uneven flow and swirling phenomena: The high-speed rotation of the magnet shaft will generate vortexes in the cooling water flow path, causing unstable cooling water flow, which in turn leads to a decrease in heat transfer efficiency and uneven cooling.

[0007] Therefore, improving the cooling efficiency and uniformity of the rotating magnet assembly that generates high heat in the sputtering process is an important issue that the industry urgently needs to address. Summary of the Invention

[0008] In view of the above problems, one embodiment of the present invention aims to provide a cooling structure that cools the rotating magnet from the periphery to the center, thereby improving cooling uniformity and suppressing eddy current phenomena.

[0009] Another objective of one embodiment of the present invention is to provide a rotating magnet and a physical vapor deposition apparatus.

[0010] According to a first aspect of the invention, a cooling structure is provided for cooling a rotating magnet, comprising at least one inlet, a chamber, at least one outlet, and a coolant: The cavity exterior surrounds one end of the rotation axis of the rotating magnet; The inlet is located on the chamber; The outlet is located at the other end of the rotating shaft; The coolant enters from the inlet of the chamber, moves from the periphery of the chamber towards the center of the rotating shaft, and flows out from the outlet.

[0011] In one possible implementation, the cooling structure further includes a coolant driving component, which is driven to rotate by the rotation of a rotating magnet, thereby driving the coolant to move from the periphery to the center.

[0012] In one possible implementation, the coolant drive assembly has a fan-shaped structure and is mounted at one end of the rotating shaft.

[0013] In one possible implementation, the coolant drive assembly includes a blade structure comprising a plurality of blades arranged about a rotation axis.

[0014] In one possible implementation, the coolant drive assembly is disposed within the chamber, with one end connected to the chamber and the other end having a concave-convex structure.

[0015] In one possible implementation, one end of the coolant drive assembly is connected to the top surface of the chamber and surrounds the rotating shaft, while the other end of the coolant drive assembly is provided with a concave-convex structure.

[0016] In one possible implementation, the coolant drive assembly is a counterweight member of the rotating shaft, and at least one surface of the counterweight member is provided with a concave-convex structure.

[0017] In one possible implementation, the inner surface of the chamber that at least externally surrounds the rotation shaft is provided with a textured structure.

[0018] In one possible implementation, the concave-convex structure includes one or more of the following: protrusions, grooves, radial trenches, and wavy structures.

[0019] According to a second aspect of the present invention, a rotating magnet is provided, comprising a magnet assembly, a rotating shaft, a driving member, and the aforementioned cooling structure. The magnet assembly is disposed at one end of the rotating shaft located within a cavity of the cooling structure, and the magnet assembly comprises a plurality of magnets. The driving member drives the rotating shaft to rotate. The cooling structure cools the rotating shaft from the cavity to the other end of the rotating shaft from the periphery towards the center.

[0020] According to a third aspect of the present invention, a physical vapor deposition apparatus is provided, comprising the aforementioned rotating magnet, target material, and process chamber: The process chamber is located below the cooling structure of the rotating magnet; The magnet assembly and one end of the rotating shaft of the rotating magnet are disposed within the cooling structure; The rotating magnet generates a rotating magnetic field, and the plasma bombards the target material under the constraint of the rotating magnetic field.

[0021] In one possible implementation, the target is mounted on the base plate of the cooling structure, which is also used to cool the target.

[0022] In one possible implementation, the target material is partially located within the chamber of the cooling structure and partially located within the process chamber.

[0023] The coolant in the cooling structure of the present invention flows from the periphery to the center, and makes full use of the rotational energy of the rotating magnet as the driving force for coolant circulation, thereby actively suppressing the swirling phenomenon and achieving uniform cooling. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of an embodiment of the cooling structure described in this invention in a rotating magnet. Figure 2 and Figure 3 This is a schematic diagram of one embodiment of the coolant drive assembly described in this invention; Figure 4 This is a schematic diagram of a second embodiment of the coolant drive assembly described in this invention; Figure 5 This is a schematic diagram of a third embodiment of the coolant drive assembly described in this invention; Figure 6 This is a schematic diagram of one embodiment of the rotating magnet described in this invention; Figure 7 This is a schematic diagram of an embodiment of the physical deposition apparatus described in this invention; The components are as follows: 100. Physical vapor deposition equipment; 10. Rotating magnet; 1. Cooling structure; 11. Coolant; 12. Inlet; 13. Outlet; 14. Coolant drive assembly; 141. Fan-shaped structure; 1411. Blade structure; 14111. Blade; 14112. Blade holder; 1412. Bearing; 1413. Bearing seat; 1414. Support base; 14141. Step; 142. Concave-convex structure; 143. Counterweight component; 15. Chamber; 151. Top cover plate; 152. Base plate; 153. Side plate; 16. Target mounting component; 2. Magnet assembly; 21. Magnet; 22. Upper mounting plate; 23. Lower mounting plate; 3. Drive component; 31. Motor; 32. Belt; 33. Gear; 4. Rotating shaft; 5. Rotation sensor; 6. Housing; 20. Process chamber; 30. Target. Detailed Implementation

[0025] Numerous specific details are set forth in the following description to provide a full understanding of the invention. However, the invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0026] The terminology used in one or more embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a” and “the” as used in one or more embodiments of the invention and in the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0027] Hereinafter, one or more embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can clearly and completely understand the present invention. When the description of well-known structures or features would unnecessarily obscure the main points of the present invention, the description of such well-known structures or features will be omitted.

[0028] In the PVD process, when a DC power supply drives a rotating magnet to form plasma in the reaction chamber to sputter the target source to deposit a thin film, the magnet undergoes thermal deformation due to high temperature, which is conducted to the target source, resulting in a decrease in film quality and a deterioration in process uniformity. Existing technologies use a water-cooled cooling structure from the center to the periphery to cool the magnet, but this has limitations in cooling efficiency and non-uniformity (such as the difficulty in achieving efficient heat exchange from the center to the periphery due to unidirectional flow, and insufficient cooling in areas of heat concentration), as well as the swirling phenomenon caused by the high-speed rotation of the magnet (vortices cause instability in water flow), which further reduces heat transfer efficiency and cooling uniformity.

[0029] To address the aforementioned technical problems in the prior art, the present invention provides a cooling structure 1 for cooling a rotating magnet 10, such as... Figure 1 As shown, the cooling structure 1 includes a coolant 11, which cools the rotating magnet 10 from the periphery to the center.

[0030] The cooling structure 1 of this invention has a cooling direction relative to the rotating magnet 10 from the periphery to the center: the coolant 11 enters from multiple points on the periphery, directly covering the high-temperature area, reducing heat concentration, and achieving a more uniform temperature distribution; the centrifugal force of the rotating magnet 10 pushes the coolant 11 towards the center, consistent with the design direction, avoiding vortex generation and improving flow stability. The cooling structure 1 of this invention significantly improves heat exchange efficiency and process uniformity by optimizing the cooling path and fluid dynamics.

[0031] In one feasible embodiment, such as Figure 1As shown, the cooling structure 1 further includes at least one inlet 12, at least one outlet 13, and a chamber 15. The inlet 12 is located at one end of the chamber 15 surrounding the rotation axis 4 of the rotating magnet 10; the outlet 13 is located at the other end of the rotation axis 4 of the rotating magnet 10 outside the chamber 15.

[0032] In one feasible embodiment, the plurality of inlets 12 are located on different sides of the chamber 15 relative to the rotation axis 4.

[0033] In one feasible embodiment, such as Figures 2-5 As shown, the cooling structure 1 also includes a coolant driving component 14, which is driven to rotate by the rotation of the rotating magnet 10, thereby driving the coolant 11 to move from the periphery to the center.

[0034] In one embodiment, such as Figure 2 and Figure 3 As shown, the coolant drive assembly 14 has a fan-shaped structure 141 and is installed at one end of the rotating shaft 4.

[0035] In one feasible embodiment, such as Figure 3 The coolant drive assembly 14 shown includes a blade structure 1411, which includes a plurality of blades 14111 arranged around a rotation axis 4.

[0036] Preferably, the blade structure 1411 further includes a blade fixing seat 14112, which is configured to install multiple blades 14111. The multiple blades 14111 can be fixedly connected to the blade fixing seat 14112 or detachably connected.

[0037] In one feasible embodiment, the coolant drive assembly 14 further includes a bearing housing 1413 and a bearing 1412, the blade structure 1411 surrounds one end of the bearing 1412, the bearing housing 1413 surrounds the other end of the bearing 1412, and the bearing 1412 surrounds one end of the rotating shaft 4.

[0038] In one feasible embodiment, the coolant drive assembly 14 further includes a support base 1414 configured to support the blade structure 1411 without hindering the rotation of the blade structure 1411. For example, the support base 1414 is provided with a step 14141 that contacts the blade structure 1411.

[0039] Preferably, the support base 1414 has a U-shaped structure, and the bearing seat 1413 is installed inside the U-shape to facilitate the disassembly and assembly of the bearing seat 1413.

[0040] The cooling structure 1 of the present invention uses a fan-shaped coolant drive assembly 14 mounted on a rotating shaft 4 to utilize the rotational energy of a magnet 21 to perform a dual function: the rotational energy of the magnet 21 generates a pumping action, which exerts a force on the coolant 11, causing it to flow into the central discharge port, thereby improving circulation efficiency; the blades 14111 block and stabilize the vortices generated in the flow path, guiding uniform flow.

[0041] In one feasible embodiment, such as Figure 4 As shown, the coolant drive assembly 14 is disposed in the chamber, one end of the coolant drive assembly 14 is connected to the chamber, and the other end has a concave-convex structure 142.

[0042] Preferably, one end of the coolant drive assembly 14 is connected to the top surface of the chamber and surrounds the rotating shaft 4, and the other end of the coolant drive assembly 14 is provided with a concave-convex structure 142.

[0043] In one feasible embodiment, such as Figure 4 As shown, the inner surface of the cavity that at least surrounds the rotating shaft 4 is provided with a concave-convex structure 142.

[0044] Preferably, the coolant drive assembly 14 is a concave-convex structure 142 disposed on the top cover plate 151 of the chamber 15 of the physical deposition apparatus facing the inner surface of the chamber.

[0045] In one embodiment, such as Figure 5 As shown, the coolant drive assembly 14 is a counterweight component 143 of the rotating shaft 4, and at least one surface of the counterweight component 143 is provided with a concave-convex structure 142.

[0046] Preferably, the top surface of the counterweight component 143 (the upper end surface surrounding one end of the rotating shaft 4) is provided with a concave-convex structure 142.

[0047] In the above embodiments, the concave-convex structure 142 includes one or more of the following: protrusions, grooves, radial grooves, and wavy structures.

[0048] This invention provides several embodiments of the coolant drive assembly 14, but the invention is not limited thereto. All structures and implementations that can effectively suppress eddies within the flow path and generate a forced propulsion force towards the central discharge port by adjusting the coolant flow rate 11 are within the scope of protection of this disclosure. The coolant drive assembly 14 may also be a combination of the above embodiments.

[0049] In the above embodiments, the coolant 11 can be cooling water or other coolants 11, and can be one type of coolant 11 or multiple types of coolants 11.

[0050] In one feasible embodiment, the cavity 15 of the cooling structure 1 includes a top cover plate 151, a side plate 153, and a bottom plate 152: The top cover plate 151 is provided with an opening through which the rotating shaft of the rotating magnet passes; The side plate 153 is supported between the top cover plate 151 and the bottom plate 152; The base plate 152 has an opening for mounting the target material 30, so that the cooling structure 1 cools the target material 30 while cooling the rotating magnet.

[0051] In one feasible embodiment, the cooling structure 1 further includes a target mounting member 16 disposed within the cavity 15 for detachably mounting the target 30.

[0052] The aforementioned target mounting component 16 can be a fixed connector (e.g., a bolt) or a snap fastener.

[0053] In a preferred embodiment, the target mounting member 16 is a snap-fit, which is mounted on the side plate of the chamber.

[0054] The present invention also provides a rotating magnet 10, such as Figure 1 , Figure 3 and Figure 6 As shown, the rotating magnet 10 includes a magnet assembly 2, a rotating shaft 4, and a driving component 3: The magnet assembly 2 includes a plurality of magnets 21; The rotating shaft 4 is connected to the magnet assembly 2; The driving component 3 drives the rotating shaft 4 to rotate, and the rotating shaft 4 drives the magnet assembly 2 to rotate.

[0055] In one feasible embodiment, such as Figure 6 As shown, the rotating magnet 10 also includes a coolant drive assembly 14: The coolant drive assembly can be mounted on the rotating shaft 4 between the magnet assembly 2 and the drive member 3 using a fan-shaped structure 141; Or / and the coolant drive assembly is mounted in the form of a counterweight 143 on the rotational shaft 4 between the magnet assembly 2 and the drive assembly 3.

[0056] In one feasible embodiment, such as Figure 1 As shown, the rotating magnet 10 also includes the cooling structure 1 in the above embodiments. The magnet assembly 2 is disposed at one end of the rotating shaft 4 located in the cavity of the cooling structure 1. The cooling structure 1 cools the rotating shaft 4 from the cavity to the other end from the periphery to the center.

[0057] In one feasible embodiment, such as Figure 6As shown, the driving component 3 includes a motor 31, which drives the rotating shaft 4 to rotate. For example, the motor 31 drives the rotating shaft 4 to rotate via a gear 33 and a belt 32.

[0058] Preferably, the motor 31 is a brushless DC motor 31.

[0059] In one feasible embodiment, such as Figure 6 As shown, the magnet assembly 2 also includes an upper mounting plate 22 and a lower mounting plate 23, with the plurality of magnets 21 located between the upper mounting plate 22 and the lower mounting plate 23.

[0060] Preferably, an insulating layer is coated on the surface of the magnet 21 to prevent the coolant from affecting the magnet.

[0061] Preferably, the magnet assembly further includes a side panel (not shown), which is disposed between the upper mounting plate and the mounting plate, surrounding the plurality of magnets to prevent the coolant from affecting the magnets. More preferably, the lower mounting plate is detachably mounted to the side panel, facilitating the installation, maintenance, and replacement of the magnets.

[0062] In one feasible embodiment, the rotating magnet 10 further includes a rotation sensor 5 for measuring parameters of the magnet 21's rotation. These parameters include one or more of the following: number of rotations, magnet 21 position, and rotational speed. For example, the number of rotations (counting pulses generated by the passing of the magnetic poles) and speed (calculated based on the number of pulses per unit time) can be measured using a Hall effect sensor to detect electrical signals generated by changes in the magnetic field. Alternatively, an incremental encoder can measure the number of rotations and speed by counting pulses, while an absolute encoder provides absolute position information. In physical vapor deposition, the parameters measured by these sensors can be used to control the magnetron sputtering process, affecting the uniformity and quality of thin film deposition, and adjusting the position and rotation state of the magnet 21 to optimize the deposition process.

[0063] In one feasible embodiment, the rotating magnet 10 further includes a housing 6, which is connected to the chamber 15 of the cooling structure 1. For example, the housing 6 is connected to the chamber 15 via a bearing seat; the rotating shaft 4 is disposed inside the housing 6 and one end extends into the chamber 15.

[0064] Figure 7 A schematic diagram of one embodiment of the physical deposition apparatus of the present invention is shown, as follows: Figure 7 As shown, the physical vapor deposition apparatus 100 includes a cooling structure 1, a rotating magnet 10, a target material 30, and a process chamber 20. The process chamber 20 is located below the cooling structure 1; The cooling structure 1 cools at least the rotating magnet 10, and one end of the magnet assembly 2 and the rotating shaft 4 of the rotating magnet 10 is disposed in the chamber 15 of the cooling structure 1. The rotating magnet 10 generates a rotating magnetic field, and the plasma bombards the target material 30 under the action of the rotating magnetic field.

[0065] The cooling structure 1 of the physical vapor deposition apparatus 100 of the present invention ensures the thermal stability of the magnet and the target source by providing coolant 11 from the periphery of the rotating magnet 10 and in a counter-current flow path to the center, thereby extending their lifespan. It can significantly improve the cooling efficiency and reliability of the rotating magnet 10, which generates high heat in the sputtering process, and significantly improve the repeatability of the PVD process and the uniformity of the deposited film thickness.

[0066] In one feasible embodiment, the target 30 is mounted on the base plate of the cooling structure 1, and the cooling structure 1 is also used to cool the target 30.

[0067] In a preferred embodiment, the target material 30 is partially located within the cavity of the cooling structure 1 and partially located within the process chamber 20. The cooling structure 1 cools the rotating magnet 10 while simultaneously cooling the target material 30.

[0068] The cooling structure 1 and process chamber 20 of the physical vapor deposition equipment of the present invention are physically isolated by the target material 30, which also isolates the rotating magnet 10 from the process chamber 20. This ensures uniform cooling of the rotating magnet and the target material, while improving the stability of the magnetic field and the reliability of the equipment, and reducing maintenance costs. The plasma, temperature fluctuations, or gaseous environment within the process chamber do not interfere with the magnetic field of the rotating magnet, ensuring magnetic field uniformity and stability. A stable magnetic field helps maintain the uniformity of the sputtering process, reduces film defects, and improves yield. The magnetic field is unaffected by process fluctuations, resulting in more consistent coating results each time, making it suitable for high-precision manufacturing. The isolation design reduces the physical or chemical impact of the process chamber on the magnet, lowers the risk of magnet contamination or damage, extends magnet life, and reduces maintenance frequency and cost.

[0069] Simultaneously cooling the rotating magnet and the target material extends their lifespan and improves magnetic field stability. This helps to ensure uniform consumption of the target material, reduces local overheating or waste, and lowers material costs.

[0070] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0071] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. The optional embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the embodiments of the present invention. These embodiments are selected and specifically described to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A cooling structure for cooling a rotating magnet, characterized in that, Includes at least one inlet, a chamber, at least one outlet, and coolant: The cavity exterior surrounds one end of the rotation axis of the rotating magnet; The inlet is located on the chamber; The outlet is located at the other end of the rotating shaft; The coolant enters from the inlet of the chamber, moves from the periphery of the chamber towards the center of the rotating shaft, and flows out from the outlet.

2. The cooling structure according to claim 1, characterized in that, It also includes a coolant drive assembly, which is driven to rotate by the rotation of a rotating magnet, thereby driving the coolant to move from the periphery to the center.

3. The cooling structure according to claim 2, characterized in that, The coolant drive assembly has a fan-shaped structure and is mounted at one end of the rotating shaft.

4. The cooling structure according to claim 3, characterized in that, The coolant drive assembly includes a blade structure comprising a plurality of blades arranged around a rotation axis.

5. The cooling structure according to claim 2, characterized in that, The coolant drive assembly is disposed in the chamber, with one end connected to the chamber and the other end having a concave-convex structure.

6. The cooling structure according to claim 5, characterized in that, One end of the coolant drive assembly is connected to the top surface of the chamber and surrounds the rotating shaft, while the other end of the coolant drive assembly is provided with a concave-convex structure.

7. The cooling structure according to claim 5, characterized in that, The coolant drive assembly is a counterweight component of the rotating shaft, and at least one surface of the counterweight component is provided with a concave-convex structure.

8. The cooling structure according to claim 1, characterized in that, The inner surface of the chamber that at least surrounds the rotating shaft has a textured surface.

9. The cooling structure according to any one of claims 5-8, characterized in that, The concave-convex structure includes one or more of the following: protrusions, grooves, radial grooves, and wavy structures.

10. A rotating magnet, characterized in that, The device includes a magnet assembly, a rotating shaft, a drive member, and a cooling structure according to any one of claims 1-9. The magnet assembly is disposed at one end of the rotating shaft located within the cavity of the cooling structure, and the magnet assembly includes a plurality of magnets. The drive member drives the rotating shaft to rotate. The cooling structure cools the rotating shaft from the cavity to the other end of the rotating shaft from the periphery to the center.

11. A physical vapor deposition apparatus, characterized in that, Includes the rotating magnet, target material, and process chamber as described in claim 10: The process chamber is located below the cooling structure of the rotating magnet; The magnet assembly and one end of the rotating shaft of the rotating magnet are disposed within the cooling structure; The rotating magnet generates a rotating magnetic field, and the plasma bombards the target material under the constraint of the rotating magnetic field.

12. The physical vapor deposition apparatus according to claim 11, characterized in that, The target material is mounted on the base plate of the cooling structure, which is also used to cool the target material.

13. The physical vapor deposition apparatus according to claim 12, characterized in that, The target material is partially located within the chamber of the cooling structure and partially located within the process chamber.

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