Sealing structure of process cavity and processing equipment of semiconductor device

Abstract

The invention discloses a sealing structure of a process cavity and processing equipment of a semiconductor device. The sealing structure comprises a first sealing piece which is located in a sealing groove between the disc handle and the pipeline, is made of liquid metal and is used for dynamically sealing a main vacuum area in the process cavity when the heating disc rotates; and the capillary structure is arranged on a first contact axial surface between the first sealing piece and the inner wall of the pipeline and a second contact axial surface between the first sealing piece and the disc handle, and is used for providing capillary force for restraining the surface tension of the liquid metal so as to maintain the liquid metal in the sealing groove. According to the sealing structure, the sealing performance of a vacuum area can be guaranteed under the high-temperature semiconductor technology, the technology environment cannot be polluted in ultrahigh vacuum, meanwhile, the sealing structure has the self-repairing capacity, tiny gaps or scratches can be automatically filled, and therefore the application duration of dynamic sealing is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and in particular to a sealing structure of a process cavity and a processing equipment of a semiconductor device. BACKGROUND

[0002] With the development of semiconductor technology, the demand for plating of new materials is increasing. These new materials often have more stringent requirements for plating process. In the processing equipment of semiconductor devices, the rotatable heating disc can provide more flexible process parameter adjustment space to meet the stringent requirements of new materials in plating thickness, composition uniformity, etc., and help to promote the innovative development of semiconductor materials and devices.

[0003] For the rotating heating disc, dynamic sealing of the vacuum area where the heating disc is located is achieved by pressing the rubber ring with the rotating shaft. However, since the rubber ring is in direct contact with the moving part (rotating shaft), friction occurs during movement, causing the rubber ring to wear. Especially in high-frequency reciprocating or high-speed scenarios, the rubber ring wears faster, thereby shortening the service life of the sealing element.

[0004] To this end, the industry also provides a scheme of using magnetic fluid to replace the rubber ring for dynamic sealing. However, since the carrier liquid of the magnetic fluid will quickly evaporate and carbonize in a high-temperature environment, the magnetic fluid will have a risk of sealing failure in a high-temperature semiconductor process environment (e.g., ≥ 150℃). Moreover, the carbonized magnetic fluid will also become a source of pollution in an ultra-high vacuum process environment. In addition, the magnetic fluid is a colloidal system formed by dispersing nanoparticles in a liquid. Under high vacuum conditions, gas can penetrate the small paths between the internal particles of the colloid, further causing the sealing to be broken.

[0005] In order to solve the above problems existing in the prior art, the technical field urgently needs a sealing technology for a process cavity, which can not only ensure the sealing of the vacuum area in a high-temperature semiconductor process, but also will not pollute the process environment in an ultra-high vacuum, and also has a self-repairing capability to automatically fill small gaps or scratches, thereby improving the application duration of dynamic sealing. SUMMARY

[0006] The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

[0007] To overcome the aforementioned deficiencies in the prior art, the present invention provides a sealing structure for a process cavity and a semiconductor device processing equipment, which not only ensures the sealing of the vacuum area under high-temperature semiconductor processes, but also does not contaminate the process environment in ultra-high vacuum. It also has self-healing capabilities, automatically filling tiny gaps or scratches, thereby extending the service life of dynamic seals.

[0008] Specifically, according to the sealing structure of the process cavity provided by the first aspect of the present invention, the process cavity includes a heating plate, the handle of which extends out of the process cavity and into a pipeline below it. The sealing structure includes: a first sealing element located in a sealing groove between the handle and the pipeline, the first sealing element being liquid metal, for dynamically sealing the main vacuum area within the process cavity when the heating plate rotates; and a capillary structure disposed on a first contact axial surface of the first sealing element and the inner wall of the pipeline, and a second contact axial surface of the first sealing element and the handle, for providing capillary force to constrain the surface tension of the liquid metal, thereby maintaining the liquid metal within the sealing groove.

[0009] Furthermore, in some embodiments of the present invention, the contact surface between the handle and / or the inner wall of the pipeline and the liquid metal is coated with an insulating film layer to prevent the liquid metal from penetrating the handle and / or the pipeline.

[0010] Furthermore, in some embodiments of the present invention, the isolation film layer is a metal film layer with good wettability with the liquid metal, so as to reduce the contact angle between the capillary structure and the liquid metal.

[0011] Furthermore, in some embodiments of the present invention, the sealing structure may further include a limiting film layer coated on the periphery of the contact shaft surface to restrict the flow path of the liquid metal.

[0012] Furthermore, in some embodiments of the present invention, the capillary structure includes a micron-scale groove structure or pore structure, or a composite groove structure, so that the capillary force applied to the liquid metal is greater than the liquid metal's own weight or centrifugal force during rotation.

[0013] Furthermore, in some embodiments of the present invention, the sealing structure further includes: a second sealing element disposed in the pipeline and located outside the first sealing element, for statically sealing the secondary vacuum zone in the pipeline located between the first sealing element and the external vacuum pump, so as to perform graded pressure reduction of the main vacuum zone via the secondary vacuum zone.

[0014] Furthermore, in some embodiments of the present invention, the second seal includes the liquid metal, rubber ring, or magnetic fluid.

[0015] Furthermore, in some embodiments of the present invention, the liquid metal is a magnetic liquid metal, and the sealing structure further includes: a magnetic field generator, disposed near the sealing groove, for generating a magnetic field gradient that decreases outward from the sealing groove, so as to provide a magnetic field force pointing towards the sealing groove, and pulling the portion of liquid metal that overflows during rotation back into the sealing groove.

[0016] Furthermore, in some embodiments of the present invention, the magnetic field generator adjusts the intensity of the generated electromagnetic field based on the rotational speed of the heating plate and / or the internal and external pressure difference at both ends of the first seal, so as to change the flow characteristics of the liquid metal.

[0017] Furthermore, the semiconductor device processing apparatus provided according to the second aspect of the present invention includes: a process chamber having a rotatable heating disk inside for performing high-temperature process reactions; and a sealing structure for the process chamber provided in the first aspect of the present invention, for dynamically sealing the main vacuum zone inside the process chamber when the heating disk is rotating during the high-temperature process reaction in the process chamber. Attached Figure Description

[0018] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0019] Figure 1 A schematic diagram of a semiconductor device processing apparatus provided according to some embodiments of the present invention is shown.

[0020] Figure 2 A schematic diagram of a sealing structure for a process cavity provided according to some embodiments of the present invention is shown.

[0021] Figure 3 A schematic diagram of a sealing structure for a process cavity provided according to other embodiments of the present invention is shown.

[0022] Figure 4 A schematic diagram of a sealing structure for a process cavity provided according to other embodiments of the present invention is shown.

[0023] Figure label:

[0024] 100 Semiconductor device processing equipment;

[0025] 110 process cavity;

[0026] 120 heating plate;

[0027] 121 handle;

[0028] 130 piping;

[0029] 131 First contact shaft surface;

[0030] 132 Second contact shaft surface;

[0031] 140 layers of insulating membrane;

[0032] 150 main vacuum pump;

[0033] 200 sealed structure;

[0034] 210 First seal;

[0035] 211 Sealing groove;

[0036] 220 Second seal;

[0037] 230 magnetic field generator;

[0038] 01 Main vacuum region;

[0039] 02 Secondary vacuum region. Detailed Implementation

[0040] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention is presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to these embodiments. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a thorough understanding of the invention, many specific details will be included in the following description. The invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the invention, some specific details will be omitted in the description.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0042] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0043] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various components, regions, layers, and / or parts, these components, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or parts. Therefore, the first components, regions, layers, and / or parts discussed below may be referred to as second components, regions, layers, and / or parts without departing from some embodiments of the present invention.

[0044] As mentioned above, for a rotating heating plate, a dynamic seal is achieved by pressing a rubber ring against the rotating shaft to seal the vacuum area where the heating plate is located. However, since the rubber ring is in direct contact with the moving parts (rotating shaft), friction occurs during movement, leading to wear of the rubber ring. To address this, the industry has also offered a solution using magnetic fluid to replace the rubber ring for dynamic sealing. However, because the carrier fluid of the magnetic fluid evaporates and carbonizes rapidly at high temperatures, there is a risk of seal failure in high-temperature semiconductor process environments (e.g., ≥150°C). Furthermore, carbonized magnetic fluid can become a source of contamination in ultra-high vacuum process environments. In addition, magnetic fluid is a colloidal system formed by dispersing nanoparticles in a liquid. Under high vacuum conditions, gas can penetrate the tiny pathways between the particles within the colloidal system, further leading to seal failure.

[0045] To address the aforementioned problems in the prior art, this invention provides a sealing structure for a process cavity and a semiconductor device processing equipment. This structure not only ensures the sealing of the vacuum area under high-temperature semiconductor processes but also prevents contamination of the process environment in ultra-high vacuum. Furthermore, it possesses self-healing capabilities, automatically filling minute gaps or scratches, thereby extending the service life of dynamic seals.

[0046] In some non-limiting embodiments, the sealing structure of the process cavity provided in the first aspect of the present invention can be configured in the processing equipment of the semiconductor device provided in the second aspect of the present invention.

[0047] The working principle of the sealing structure of the above-mentioned process cavity will be described below with reference to some embodiments of semiconductor device processing equipment. Those skilled in the art will understand that these embodiments of the sealing structure of the process cavity are merely some non-limiting implementations provided by the present invention, intended to clearly demonstrate the main concept of the invention and provide some specific solutions convenient for public implementation, rather than being intended to limit all operating methods or functions of the semiconductor device processing equipment.

[0048] Please refer to Figure 1 , Figure 1 A schematic diagram of a semiconductor device processing apparatus provided according to some embodiments of the present invention is shown.

[0049] like Figure 1 As shown, in some embodiments of the present invention, the semiconductor device processing equipment 100 may include a process chamber 110 and a sealing structure 200 for the process chamber. The process chamber 110 may be connected to an external main vacuum pump 150 for evacuating the process chamber 110 to the vacuum level required for the process. A rotatable heating plate 120 may be provided inside the process chamber 110. The heating plate 120 may support the wafer and is used to rotate the wafer during high-temperature process reactions to improve the uniformity of the reaction on the wafer surface.

[0050] Optionally, such as Figure 1 As shown, a single process chamber 110 may include multiple processing stations. Each processing station is equipped with a heating plate 120. In this embodiment, multiple wafers can be processed in a single process, thereby improving equipment production efficiency.

[0051] Continue as Figure 1 As shown, in the semiconductor device processing equipment 100, the handle 121 of the heating plate 120 extends out of the process chamber 110 and into the pipe 130 below it. The other end of the pipe 130 can be connected to an external low-vacuum pump (not shown in the figure). The low-vacuum pump, in conjunction with the main vacuum pump 150, works together to extract the gas from the process chamber 110, thereby providing a clean vacuum environment for the semiconductor process. When a high-temperature process reaction is carried out in the process chamber 110, the heating plate 120 is in a rotating state and can dynamically seal the main vacuum zone 01 within the process chamber 110 via the sealing structure 200 of the process chamber.

[0052] Specifically, please refer to Figure 2 . Figure 2 A schematic diagram of a sealing structure for a process cavity provided according to some embodiments of the present invention is shown.

[0053] like Figure 2As shown, in some embodiments, the sealing structure 200 may include a first seal 210 and a capillary structure. The first seal 210 may be located in a sealing groove 211 between the handle 121 and the inner wall of the conduit 130 to laterally fill the gap between the handle 121 and the conduit 130. The first seal 210 may seal and isolate the main vacuum zone 01 located inside the process chamber 110 from the atmospheric environment located outside the first seal 210.

[0054] Furthermore, the first seal 210 can be liquid metal. The first seal 210 can be used to dynamically seal the main vacuum zone 01 within the process chamber 110 when the heating plate 120 rotates and its handle 121 is also rotating. Additionally, a capillary structure can be provided on the inner wall of the pipe 130, on the contact surface with the first seal 210. The capillary structure can provide capillary force to constrain the surface tension of the liquid metal, thereby maintaining the liquid metal within the sealing groove 211.

[0055] In the embodiments provided by the present invention, the first sealing element 210, serving as the main vacuum zone 01 of the dynamic seal, is liquid metal. The viscosity of liquid metal (such as Galinstan) is close to that of water, much lower than that of grease or polymers. This means that liquid metal is easily flowable and can flow into any tiny gaps that appear during the sealing process. Moreover, under the action of surface tension, liquid metal will spontaneously fill narrow gaps. Therefore, during movement, due to its fluidity, liquid metal can fill tiny gaps or scratches in real time, possessing self-healing capabilities, thereby avoiding gas leakage and reducing the impact of rubber ring wear on the performance of subsequently prepared films in the prior art. Furthermore, even if a seal failure occurs, liquid metal can quickly restore the sealing effect by replenishing the medium, and its maintenance convenience is superior to that of solid seals. The main sealing element of liquid metal has the characteristics of long life and low wear. Since liquid metal is a lubricating medium, there is no solid contact friction during the rotation of the heating plate 120, resulting in minimal wear on the moving parts (plate handle 121), extending its lifespan to tens of thousands to hundreds of thousands of hours.

[0056] Furthermore, in terms of materials, the working fluid in liquid metal seals is an inorganic metal, while the working fluid in magnetohydrodynamic (MHD) seals is a colloidal suspension formed by organic carrier fluid encapsulating nanoparticles. Liquid metals can maintain their liquid state and performance at high temperatures, exhibiting strong thermal stability. In contrast, the carrier fluid in MHDs rapidly evaporates and carbonizes at high temperatures, leading to permanent seal failure. Moreover, liquid metals have extremely low vapor pressure (≤10). -10 The pressure drop (Pa) is several orders of magnitude lower than that of the best magnetohydrodynamic carrier fluid, therefore it will not become a source of contamination even in ultra-high vacuum environments. In other words, in this embodiment, the liquid metal, as the first sealing element 210, has vacuum compatibility and can meet the requirements of ultra-high vacuum (10 Pa). -8 ~10-12 Pa) demand.

[0057] Furthermore, liquid metals possess structural advantages. As a continuous, dense liquid phase, liquid metal itself acts as a powerful physical barrier. It can directly resist vacuum pressure differences through its hydrostatic pressure and surface tension, thereby blocking the passage of gas molecules. In contrast, magnetohydrodynamics is a colloidal system formed by nanoparticles dispersed in a liquid. Therefore, under high vacuum conditions, gas can penetrate the tiny pathways between the particles within the colloid, leading to seal failure.

[0058] However, as Figure 2 As shown, when the handle 121 rotates at high speed within the pipe 130, its outer surface comes into direct contact with the liquid metal in the gap. Because the liquid metal is viscous, the rotation of the handle 121 causes the liquid metal layer adhering to its surface to rotate as well. However, the inner wall of the pipe 130 is fixed, so the liquid metal layer adhering to it remains almost stationary. This relative motion—the axial liquid layer moving while the pipe wall liquid layer remains stationary—generates shear force within the liquid metal, creating a risk of liquid film rupture. Once the liquid film ruptures, a gas channel will appear in the gap, leading to seal failure.

[0059] In this regard, such as Figure 2 As shown in the magnified area I, to counteract the aforementioned shear force, in some optional embodiments, capillary structures can be machined on the first contact surface 131 located on the inner wall of the pipe 130 and in contact with the first seal 210, and on the second contact surface 132 located on the handle 121 and in contact with the first seal 210. The capillary force provided by the capillary structure, which constrains the surface tension of the liquid metal, locks the liquid metal within the sealing groove 211. The use of capillary force to lock the liquid metal enhances the liquid metal retention force and improves sealing performance.

[0060] During the sealing process of liquid metal, the capillary structure maintains the stability of the liquid film through hydrodynamic pressure. Specifically, when the handle 121 rotates, it can drive the liquid metal into the wide end (i.e., the inlet) of the capillary structure. The liquid metal can flow along the shape of the capillary channel towards its narrow end. As the space gradually decreases, the liquid metal is compressed, generating directional hydrodynamic pressure. This hydrodynamic pressure pushes the liquid metal to flow in the opposite direction of the shear force, thereby counteracting the thinning tendency of the shear force on the liquid film, allowing the liquid film to maintain a uniform thickness (typically a few micrometers to tens of micrometers) and continuously cover the entire sealing gap.

[0061] Furthermore, Jurín's law can be used to understand the sealing structure 200 of the process cavity provided by this invention. Jurín's law can quantitatively describe the height to which liquid metal rises (or falls) in a capillary structure by the balance between the surface tension and gravity of the liquid metal, thereby revealing the regulation law of surface tension, contact angle, liquid density, and capillary structure size on the dynamic sealing of liquid metal. Liquid metal can spontaneously fill the pores within the capillary structure in the micro-channels under the influence of surface tension (γ) and contact angle (θ).

[0062] Specifically, the formula for Jurín's Law is as follows:

[0063]

[0064] in, Indicates the surface tension of liquid metal. Indicates the contact angle. Indicates the density of liquid metal. This represents the radius of the capillary structure (i.e., the pore width). This indicates the equilibrium height of the liquid metal within the capillary structure.

[0065] According to the formula of Jurín's law mentioned above, when the pores of the capillary structure... The smaller the value, the larger the equilibrium height h, indicating a stronger capillary force and thus a more stable sealing effect. In some preferred embodiments, the capillary structure can be a micrometer-scale groove or pore structure. At this tiny pore scale, the capillary force (i.e., contractile force) applied to the liquid metal to constrain its surface tension is greater than the liquid metal's own weight or centrifugal force during rotation, thereby constraining the liquid metal and locking it within the sealing groove 211, thus maintaining a stable sealing interface under dynamic conditions.

[0066] In some alternative embodiments, the capillary structure can be a microgroove such as a spiral groove, a rectangular groove, or a porous layer. For example, micron-sized concentric circular grooves or spiral grooves (e.g., width 50-200 μm, depth 10-50 μm) can be machined on the first contact shaft surface 131 to fit the rotating shaft of the handle 121 and enhance the sealing pressure.

[0067] In some alternative embodiments, the capillary structure can be a composite structure. For example, a composite hierarchical capillary channel, including a primary wide groove and a secondary narrow groove, can be machined on the first contact axial surface 131. The porosity of the primary wide groove can be around 200 μm, which can be used to store liquid metal. The porosity of the secondary narrow groove can be around 50 μm, which can be used to enhance the capillary locking force. Furthermore, the composite hierarchical capillary channel can also include a tertiary groove with even smaller porosity to ensure that the centrifugal force of the liquid metal at high rotational speeds is less than the capillary force.

[0068] In some alternative embodiments, the capillary structure can be a composite groove structure. That is, the capillary structure can combine various groove types such as spiral grooves, rectangular grooves, porous layers, and microgrooves.

[0069] In addition, in some other embodiments, the capillary structure can also be designed as a biomimetic porous structure.

[0070] Specifically, in some preferred embodiments, the capillary structure can be designed as a dendritic fractal capillary network. The dendritic fractal capillary network offers ultra-high liquid supply efficiency and uniformity, ensuring that liquid metal is replenished throughout the sealing interface and preventing localized drying. Furthermore, the dendritic fractal capillary network possesses excellent self-healing capabilities; even if a local channel is damaged, other branches can still supply liquid to that area through the fractal network. Moreover, the dendritic fractal capillary network is not dependent on a single channel, exhibiting strong robustness. Optionally, the capillary structure may include wide and deep primary channels as the main liquid supply channels, and may also include secondary and tertiary branches, which, through continuous subdivision, deliver liquid metal to the entire sealing surface.

[0071] In other preferred embodiments, the capillary structure can also be designed as a cactus spine-like structure. Because cactus spines have a gradient taper and asymmetrical microgrooves, they can generate a Laplace pressure differential, directing dew towards the base. Therefore, mimicking this characteristic, capillary channels with a tapered gradient can be designed. In this embodiment, the width or depth of the channels can gradually decrease from one end to the other, thereby generating a net conveying force pointing towards the narrow end. The gradient direction can be designed to point towards the axis of the rotating handle 121 to generate a capillary pumping force opposite to centrifugal force, thereby actively pulling the liquid metal back to the sealing area.

[0072] Please refer to the formula of Jurín's Law above. According to the formula, the surface tension of liquid metal is... The larger the value, the greater the equilibrium height h, indicating stronger capillary force and thus a more stable sealing effect. For this purpose, factors including, but not limited to, surface tension can be used. Larger gallium-based alloys. For example, the first seal 210 can be made of gallium indium tin alloy (GaInTT). The surface tension of GaInTT alloys... It is approximately 0.718 N / m. Through its strong surface tension, the liquid metal can resist the influence of external forces such as gravity and centrifugal force, remaining stably within the gap of the sealing groove. Liquid metals exhibit good wide temperature and environmental adaptability, capable of withstanding extreme temperatures. For example, gallium-based alloys can remain in a liquid state from -20℃ to 200℃.

[0073] However, because gallium atoms in the liquid metal of gallium-based alloys can penetrate along the metal and disrupt grain boundary bonding, the material can fracture brittlely. In the semiconductor device processing equipment 100, most components are made of metallic materials. Therefore, if the liquid metal comes into direct contact with the handle 121 of the heating plate and the conduit 130, the liquid metal will penetrate, thereby embrittled the substrate of the handle 121 and the conduit 130.

[0074] In response, continue as Figure 2 As shown in the magnified area I, in some optional embodiments, the first contact surface 131 of the inner wall of the conduit 130 with the liquid metal, and / or the second contact surface 132 of the handle 121 with the liquid metal, may be coated with an insulating film layer 140. The insulating film layer 140 can prevent the liquid metal from penetrating into the handle 121 and / or the conduit 130, thus preventing the liquid metal from penetrating and embrittled the substrate.

[0075] Furthermore, since the components in the semiconductor device processing equipment 100 are mostly made of metallic materials such as stainless steel and aluminum alloys, a dense oxide film (such as Al2O3) naturally forms on the surface of these materials. Although this oxide film is hydrophilic, it has extremely poor wettability with liquid metals (especially gallium-based alloys), resulting in a low contact angle between the liquid metal and the capillary structure. The surface area is relatively large. This causes the liquid metal on the oxide film surface to form spherical shapes like mercury, preventing it from spreading and forming an effective sealing interface.

[0076] According to Jurín's law, when the contact angle... At an angle less than 90°, liquid metal can form a smooth spreading pattern on the capillary surface. Good wettability exists between the two. However, when the contact angle... When the angle is greater than 90°, the liquid metal forms a raised droplet shape on the capillary surface. There is a strong repulsion between the two. To address this, the isolation film layer 140 coated on the first contact axial surface 131 and / or the second contact axial surface 132 can be made of a metal with good wettability to the liquid metal, such as gold or nickel, thereby reducing the contact angle between the liquid metal and the capillary surface. This allows the liquid metal to spread evenly and form a sealed film.

[0077] Based on this, in some optional embodiments, a limiting film layer (not shown in the figures) can also be coated around the first contact shaft surface 131 and / or the second contact shaft surface 132. Optionally, the limiting film layer can be made of a hydrophobic material, such as an oxide layer. By coating the non-contact shaft surface area with a limiting film layer, the flow path of the liquid metal can be restricted, confining it to a preset path (i.e., within the sealing groove path range corresponding to the contact shaft surface), preventing the liquid metal from overflowing into the non-sealed area.

[0078] Furthermore, the aforementioned isolation membrane layer 140, limiting membrane layer, and capillary structure can be designed in conjunction. In some alternative embodiments, the capillary structure can be designed as a structure resembling the back of a desert beetle. Because the wings on the back of a desert beetle have alternating hydrophilic and hydrophobic micro-regions, they can collect and directionally transport water droplets from mist. Following this characteristic, a capillary structure with alternating hydrophilic and hydrophobic patterned surfaces can be created on the first contact axial surface 131. The hydrophilic regions can be plated with a gold film to guide the spread of liquid metal, directing it to the critical areas requiring sealing. The hydrophobic regions can be plated with an oxide layer to restrict the flow of liquid metal, confining it along a predetermined path and preventing it from overflowing into unsealed areas.

[0079] Next, see Figure 3 , Figure 3 A schematic diagram of a sealing structure for a process cavity provided according to other embodiments of the present invention is shown.

[0080] Combination Figure 1 and Figure 3 In some alternative embodiments, the sealing structure 200 of the process chamber may further include a second seal 220. The rotational shaft of the handle 121 extends from inside the chamber through the seal of the first seal 210 and into the secondary vacuum zone 02. The second seal 220 may be disposed in the pipeline 130 and located outside the first seal 210, for statically sealing the secondary vacuum zone 02 located between the first seal 210 and the external low vacuum pump in the pipeline 130. The secondary vacuum zone 02 is another separately evacuated intermediate chamber set between the primary vacuum zone 01 and the external atmosphere. The secondary vacuum zone 02 can be flanged to the low vacuum pump so that the secondary vacuum zone 02 meets the required vacuum conditions (e.g., a vacuum degree of approximately 10). 3 Pa). The secondary vacuum zone 02 can reduce the pressure of the main vacuum zone 01 in stages, thereby reducing the liquid column height required for the liquid metal seal (i.e., reducing the static pressure burden of the sealing system).

[0081] Specifically, taking a liquid metal alloy composed of gallium, indium, and tin as an example, in a traditional single-stage sealing configuration, the liquid metal column height needs to directly balance the pressure difference between atmospheric pressure and the high vacuum pressure difference in the main vacuum zone 01. For example, the pressure difference ΔP between the two is approximately 1 atm. The required liquid metal column height for single-stage pressure reduction... It can be obtained through the following formula

[0082]

[0083] in, This is the density of a liquid metal composed of gallium, indium, and tin.

[0084] When staged sealing is achieved through the intermediate cavity of the secondary vacuum zone 02, the liquid column height only needs to balance the small pressure difference between the secondary vacuum zone 02 and the main vacuum zone 01. For example, the pressure difference ΔP' between the two is approximately 0.01 atm. In this case, the required liquid metal column height for staged pressure reduction is... It can be obtained using the following formula:

[0085]

[0086] The comparison of the two examples above shows that the liquid metal column height can be significantly reduced to 1%. In other words, in this embodiment, by adding a secondary vacuum zone 02 outside the main vacuum zone 01 for graded pressure reduction, the pressure difference borne by the liquid metal can be significantly reduced, thereby reducing the liquid column height requirement.

[0087] Optionally, since the secondary vacuum region 02 is far from the process chamber 110 where the high-temperature semiconductor process reaction takes place, the second sealing element 220 can be a rubber ring or a magnetic fluid. Alternatively, the second sealing element 220 can also be liquid metal. Because the pressure difference between the secondary vacuum region 02 and the atmospheric end is much smaller than the pressure difference between the main vacuum region 01 and the atmospheric end, the height of the liquid metal column in the second sealing element 220 can be relatively reduced.

[0088] Next, please refer to Figure 4 , Figure 4 A schematic diagram of a sealing structure for a process cavity provided according to other embodiments of the present invention is shown.

[0089] like Figure 4 As shown, in some preferred embodiments, the liquid metal may include magnetic particles to form a magnetic liquid metal. The sealing structure 200 of the process chamber may also include a magnetic field generator 230. The magnetic field generator 230 may be located near the sealing groove 211 to generate a magnetic field gradient that decreases outward from the sealing groove 211. That is, the magnetic field generated by the magnetic field generator 230 is not uniform. The magnetic field generated in the region where the sealing groove 211 is located is the strongest, and the magnetic field strength decreases rapidly outside this region. The magnetic field strength is the greatest at the sealing groove 211 and decreases towards the external space, thus forming a magnetic field gradient. The direction of the magnetic field gradient is from the external space of the weak magnetic region to the sealing groove 211 of the strong magnetic region, and correspondingly, a magnetic force pointing towards the center of the sealing groove 211 is generated.

[0090] When the liquid metal is in a stable state, it is confined within the sealing groove 211, where the magnetic field is strongest, and is in a state of mechanical equilibrium. When the heating plate 120 rotates, the liquid metal is impacted, and some of it is squeezed out of the sealing groove 211. This overflowing liquid metal enters a region with a weaker external magnetic field. At this time, the overflowing liquid is subjected to a strong magnetic force pointing towards the center of the sealing groove 211 in the strong magnetic region. Under the action of this magnetic force, the overflowing liquid metal is pulled back into the sealing groove 211, completing the automatic resealing of the liquid metal. In this embodiment, by adding magnetic particles to the liquid metal and adding a magnetic field generator 230, the impact resistance and vibration resistance of the liquid metal seal can be improved, enabling it to automatically reseal under external force.

[0091] In the above embodiments, for the dynamic sealing of magnetic liquid metal confined by an external magnetic field, the ultimate pressure difference ΔP across the first sealing element 210 is... max The pressure difference is determined by both capillary force and magnetic force. When the pressure difference across the actual first seal 210 (such as the pressure difference between the main vacuum zone 01 and the external atmosphere) is less than ΔPmax, there is no need to set up a secondary vacuum zone 02 for pressure division. In other words, by adding magnetic particles to the liquid metal, the dependence on the secondary vacuum zone 02 can be reduced.

[0092] Furthermore, the magnetic field generator 230 can dynamically adjust the intensity of the generated electromagnetic field based on the rotational speed of the heating plate and / or the internal and external pressure difference across the first seal 210, thereby changing the flow characteristics of the liquid metal in real time. By adjusting the intensity of the electromagnetic field, the sealing effect of the first seal of the liquid metal can be ensured under various operating conditions. Optionally, the magnetic field generator 230 can be a permanent magnet or an electromagnetic coil of different shapes. The permanent magnet or electromagnetic coil can be installed outside the pipe 130 corresponding to the sealing groove 211.

[0093] In summary, the present invention provides a sealing structure for a process cavity and a semiconductor device processing equipment, which not only ensures the sealing of the vacuum area under high-temperature semiconductor processes, but also does not contaminate the process environment in ultra-high vacuum. It also has self-healing capabilities, which can automatically fill tiny gaps or scratches, thereby extending the service life of dynamic seals.

[0094] The prior description of this disclosure is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not intended to be limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sealing structure for a process cavity, the process cavity including a heating plate, the handle of the heating plate extending out of the process cavity and into a pipe below it, characterized in that, The sealing structure includes: A first seal, located in a sealing groove between the disk handle and the pipeline, is made of liquid metal and is used to dynamically seal the main vacuum zone within the process chamber when the heating disk rotates; and A capillary structure is provided on the first contact surface between the first seal and the inner wall of the pipeline, and on the second contact surface between the seal and the handle, for providing capillary force to constrain the surface tension of the liquid metal, so as to keep the liquid metal within the sealing groove.

2. The sealing structure as described in claim 1, characterized in that, The contact surfaces of the handle and / or the inner walls of the pipes with the liquid metal are coated with an insulating film to prevent the liquid metal from penetrating the handle and / or the pipes.

3. The sealing structure as described in claim 2, characterized in that, The isolation film is a metal film layer with good wettability with the liquid metal, so as to reduce the contact angle between the capillary structure and the liquid metal.

4. The sealing structure as described in claim 3, characterized in that, It may also include a limiting film layer coated on the periphery of the contact shaft surface to restrict the flow path of the liquid metal.

5. The sealing structure as described in claim 1, characterized in that, The capillary structure includes micron-scale groove or pore structures, or composite groove structures, such that the capillary force applied to the liquid metal is greater than the liquid metal's own weight or centrifugal force during rotation.

6. The sealing structure as described in claim 1, characterized in that, Also includes: The second seal is disposed in the pipeline and located outside the first seal, for statically sealing the secondary vacuum zone in the pipeline located between the first seal and the external vacuum pump, so as to perform graded pressure reduction of the main vacuum zone via the secondary vacuum zone.

7. The sealing structure as described in claim 6, characterized in that, The second seal includes the liquid metal, rubber ring, or magnetorheological fluid.

8. The sealing structure as described in claim 1, characterized in that, The liquid metal is a magnetic liquid metal, and the sealing structure further includes a magnetic field generator located near the sealing groove to generate a magnetic field gradient that decreases outward from the sealing groove, so as to provide a magnetic field force pointing towards the sealing groove and pull the liquid metal that overflows during rotation back into the sealing groove.

9. The sealing structure as described in claim 8, characterized in that, The magnetic field generator adjusts the intensity of the generated electromagnetic field based on the rotational speed of the heating plate and / or the internal and external pressure difference at both ends of the first seal, so as to change the flow characteristics of the liquid metal.

10. A semiconductor device processing apparatus, characterized in that, include: The process chamber contains a rotatable heating plate for high-temperature process reactions. as well as The sealing structure of the process cavity as described in any one of claims 1 to 9 is used to dynamically seal the main vacuum zone within the process cavity when the heating plate is rotating during a high-temperature process reaction within the process cavity.

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