Support assembly and measuring device

Abstract

An embodiment of the present application provides a support assembly and a measuring device, the support assembly comprising a base body and a constraint structure. The base body has a bearing surface, and a plurality of air holes are arranged on the bearing surface, the plurality of air holes being used for spraying gas to form an air cushion supporting an object to be supported, the air cushion being located in a space between the bearing surface and the object to be supported. The constraint structure is arranged on the base body and surrounds an outer periphery of the object to be supported, and the constraint structure has an inner side wall, a gap being formed between the inner side wall and an outer side wall of the object to be supported, the gap being used for changing a flow field and a dissipation path of the gas to reduce dissipation of the gas from the space to the outer periphery. By changing the flow field and the dissipation path of the gas, additional flow resistance introduced by the constraint structure needs to be overcome when the gas dissipates outward, the distribution of the flow field and the pressure inside the gas is changed by increasing the flow resistance of the gas and reducing the discharge area, the average pressure in the air cushion is improved, the lifting force of the air cushion is increased, and therefore a high-warp sheet product can be lifted.

Description

Technical Field

[0001] This application relates to the field of semiconductor device technology, and in particular, to a support component and a measuring device. Background Technology

[0002] In the fields of semiconductor manufacturing, advanced packaging, and precision measurement, thin-film products such as wafers often require stress-free, highly stable, non-contact support during processing or inspection. Common air-bearing support devices create a non-contact support air cushion between the support surface and the thin-film product by spraying gas through multiple air holes on the substrate's bearing surface.

[0003] However, due to the extremely small thickness of thin-film products (tens of micrometers or even a few micrometers), their resistance to bending deformation is drastically reduced. Even slight internal stress or uneven external forces can lead to significant warping. Moreover, after the thinning process, any residual stress (thermal stress, intrinsic stress) generated throughout the manufacturing process can more easily exacerbate the warping problem. Thus, after processes such as cleaning, transfer, photolithography, and bonding, the warping problem of thin-film products is very serious. When dealing with highly warped surfaces, traditional adsorption or mechanical clamping methods are prone to causing local suspension or overpressure, making it impossible to clamp the thin-film product flat, which seriously affects the accuracy of measurements and the yield of subsequent production. Summary of the Invention

[0004] In view of this, this application provides a support component and a measuring device, which aims to solve to some extent the problem that thin wafer products cannot be clamped flat during the support process in semiconductor manufacturing, which seriously affects the accuracy of measurement and the yield of production.

[0005] In a first aspect, one embodiment of this application provides a support component, which includes a substrate and a constraint structure. The substrate has a bearing surface, and a plurality of air holes are provided on the bearing surface for ejecting gas to form an air cushion supporting an object to be supported. The air cushion is located in the space between the bearing surface and the object to be supported. The constraint structure is disposed on the substrate and surrounds the outer periphery of the object to be supported. The constraint structure has an inner sidewall, and a gap is formed between the inner sidewall and the outer sidewall of the object to be supported. The gap is used to change the gas flow field and dispersion path to reduce gas dispersion from the space to the outer periphery.

[0006] Secondly, an embodiment of this application also provides a measuring device, which includes any of the above-mentioned support components and a measuring unit, wherein the measuring unit is used to perform measurement when the object to be detected is supported by the support components.

[0007] In this way, the inner wall facing the space is equivalent to forming a physical barrier on the outside of the air cushion, so that the gas cannot escape freely from the outside of the air cushion. It needs to flow radially from the center of the air cushion to the edge of the air cushion, and then turn 90 degrees to flow into the gap.

[0008] Because the gas escape path is altered, the total flow resistance becomes the sum of the flow resistance in the radial portion of the air cushion and the flow resistance in the gap portion, effectively increasing the flow resistance. Furthermore, the gas venting area decreases, and this change in venting area alters the flow field and pressure distribution within the gas. Thus, the smaller venting area causes gas to accumulate at the gaps (i.e., the edges of the air cushion), leading to an increase in local pressure in that area. The larger edge pressure, in turn, affects the pressure distribution of the air cushion, increasing the overall pressure curve from the center to the edge. This helps to increase the average gas pressure within the air cushion, thereby helping to raise the height of the supported object with the same gas supply. It also allows maintaining the same target pressure with a smaller gas supply, further improving gas utilization. This, in turn, helps support thin sheet products with significant warpage, thus improving measurement accuracy and production yield. Attached Figure Description

[0009] It should be understood that the following figures only illustrate certain embodiments of this application and should not be construed as limiting the scope.

[0010] It should be understood that the same or similar reference numerals are used in the accompanying drawings to denote the same or similar elements.

[0011] It should be understood that the accompanying drawings are only schematic, and the dimensions and scales of the elements in the drawings are not necessarily precise.

[0012] Figure 1 This is a schematic diagram of the structure of a support component provided in an embodiment of this application.

[0013] Figure 2 A cross-sectional view of a support component provided in an embodiment of this application.

[0014] Figure 3 This is a schematic diagram of the airflow path of a support component provided in an embodiment of this application.

[0015] Figure 4 This is a schematic diagram of a partial structure of a support component provided in an embodiment of this application.

[0016] Figure 5 This is a schematic diagram of a partial structure of a support component provided in an embodiment of this application.

[0017] Figure 6 A cross-sectional view of the center position of a support component provided in an embodiment of this application.

[0018] Figure 7 This is a schematic diagram of the structure of a flow equalization disk provided in an embodiment of this application.

[0019] Figure 8 This is a schematic diagram of the flow equalization disk body provided in another embodiment of this application.

[0020] Figure 9 This is a schematic diagram of the flow equalization disk body provided in another embodiment of this application.

[0021] Figure 10 This is a schematic diagram of the flow equalization disk body provided in another embodiment of this application.

[0022] Figure 11 This is a schematic diagram of the flow distribution channel of the flow equalization disk body provided in an embodiment of this application.

[0023] Figure 12 This is a schematic diagram of the flow distribution channel of the flow equalization disk body provided in another embodiment of this application.

[0024] Figure 13 This is a schematic diagram of the flow distribution channel of the flow equalization disk body provided in another embodiment of this application.

[0025] Figure 14 A flowchart illustrating the use of a support component provided in an embodiment of this application.

[0026] Figure 15 This is a schematic diagram of the structure of a measuring device provided in an embodiment of this application.

[0027] Figure 16 Based on Figure 1 A comparison of simulation and experimental images of the provided support components supporting a 12-inch thin sheet product with air flotation.

[0028] Figure 17 Based on Figure 1 A comparison chart showing the gas flow rate of a 12-inch sheet product supported by air flotation and the gas flow rate of a 12-inch sheet product supported by air flotation without a constraint structure.

[0029] Figure label: Support component 100; object W to be supported. Components: Base 10, Outlet disc 12, Pressure stabilizing disc 13, First chamber 131, Flow equalization disc 14, Throttling orifice 141, Flow splitting channel 142, Throttling disc 15, Pressure control unit 161, Positive pressure control unit 162, Negative pressure control unit 163, Flow control unit 165, Second chamber 132, Lifting pin 17, Floating support frame 18, Fixed support frame 181, Height sensor 19, Capacitive sensor 191. Bearing surface 20, air hole 21, first air nozzle 211, second air nozzle 212, air outlet 213, air intake 214. Constraint structure 30, inner wall 301, gap 302, constraint ring 305, outer wall 307. Measuring device 200, measuring unit 210. Detailed Implementation

[0030] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that there are various ways to implement this application, and it should not be construed as being limited to the embodiments described herein. The embodiments described herein are only for a more thorough and clear understanding of this application.

[0031] Application Overview: In semiconductor manufacturing, advanced processes are shifting from planar miniaturization to three-dimensional integration and advanced packaging, which includes not only the reduction in chip size (such as 7 nm, 5 nm, 3 nm, etc.), but also breakthroughs in complex process and material technologies.

[0032] In particular, by using "three-dimensional integration and advanced packaging" technology, multiple chips with different processes and functions (such as logic chips, memory, and RF modules) can be integrated into one package, thereby overcoming the difficulty of miniaturizing a single chip and achieving system-level performance improvement.

[0033] Thin-film products were developed to enable 3D stacking. Thin-film products are used throughout the entire chain from chip manufacturing to advanced packaging to achieve ultimate spatial integration and electrical performance, making it possible to make devices thinner and lighter (such as foldable screen phones) and to leapfrog in computing power (such as HBM high-bandwidth memory).

[0034] However, due to the extremely small thickness of wafer products (tens of micrometers or even a few micrometers), their resistance to bending deformation is drastically reduced. Even slight internal stress or uneven external forces can lead to significant warping. Moreover, after the thinning process, any residual stress (thermal stress, intrinsic stress) generated throughout the manufacturing process is more likely to exacerbate the warping problem. Thus, after processes such as cleaning, transfer, photolithography, and bonding, the residual stress generated accumulates within the wafer, further intensifying the warping problem of wafer products. The warping morphology mainly manifests as overall "convex" or "concave" bending, as well as superimposed local irregular deformations, with warping amounts reaching thousands of micrometers.

[0035] Therefore, measurement equipment for thin-film products (such as warp / morphology measurement, critical dimension measurement, bonding alignment and packaging flatness inspection systems) not only need to have the measurement capability to cover a large warp range, but also must ensure that the wafer being measured does not introduce additional stress due to the bearing method, so as to complete accurate measurement in a state close to the original state.

[0036] However, as a typical thin-film product, existing measurement equipment is mainly designed for wafers with relatively limited warpage. Under high warpage, it is difficult to form uniform and reliable surface contact with traditional vacuum adsorption or mechanical support platforms, which seriously affects the process accuracy of multilayer stacking. At the same time, it may cause secondary deformation and stress redistribution problems due to local suspension or local overpressure. Therefore, it cannot meet the requirements of supporting, clamping and high-precision measurement of wafers with large warpage.

[0037] In-depth analysis reveals that when supporting thin sheet products with high warpage (reaching thousands of micrometers), the uneven distribution of distance between the sheet product and the supporting surface makes it easier for gas to escape rapidly from areas with larger distances, making it difficult to establish a sufficiently supportive air cushion in areas with smaller distances. Increasing the air supply flow rate to ensure the sheet product floats as a whole can easily induce airflow turbulence and fluctuations in suspension height, compromising the stability of the support structure.

[0038] To overcome the above problems, refer to Figures 1 to 16 This application provides a support assembly 100 and a measuring device 200. A constraint structure 30 is provided on the bearing surface 20 of the support assembly 100 to change the gas flow field and escape path. This causes the gas to overcome the additional flow resistance introduced by the constraint structure 30 when it escapes outward. By increasing the gas flow resistance and reducing the leakage area, the flow field and pressure distribution inside the gas are changed. In this way, under the same gas supply flow rate, it is beneficial to increase the average pressure inside the air cushion, thereby increasing the lifting force of the air cushion and thus helping to lift highly warped sheet products. In addition, while obtaining the same lifting force and air buoyancy height, the constraint structure 30 helps to reduce the required gas supply flow rate, thereby helping to improve gas utilization and help to obtain a more stable air buoyancy state.

[0039] Before going into detail about the specific structure, it is necessary to clarify and define some key terms involved in this application to ensure the accuracy and consistency of the understanding of the technical solution.

[0040] Thin sheet products: This refers to any sheet-like object with a relatively large area and a small thickness, which is prone to deformation due to its own weight or residual stress when supported. Examples include, but are not limited to: semiconductor wafers, glass substrates, ceramic substrates, flexible display panels, thin metal sheets, or photovoltaic silicon wafers.

[0041] Matrix: Generally refers to any main structure having a surface for supporting sheet products. For example, including but not limited to support components with internal gas flow channels (such as air-floating chucks), carriers with porous internal materials, or platform structures with integrated gas supply systems.

[0042] Supporting surface: Generally refers to the surface area on the substrate that directly or indirectly (through air cushions) supports the sheet product. For example, it includes, but is not limited to, a flat surface, a surface with micro- or nano-structures, or a virtual plane composed of multiple independent support points.

[0043] Pores: Generally refers to any form of opening or channel formed on a bearing surface for the expulsion and / or suction of gas. Examples include, but are not limited to, precision-machined nozzles, micropores formed by laser drilling, air outlet or suction areas formed by the pores of porous materials themselves, or slits formed by microgroove arrays.

[0044] Constraint structure: Generally refers to any physical structure located on the outer periphery of an object to be supported, used to apply additional flow resistance to gas escaping from the space between the bearing surface and the sheet product to the outer periphery, thereby altering the gas flow field and escape path. Examples include, but are not limited to, continuous annular walls, arrays of multiple discrete baffles or columns, inflatable enclosures, or raised enclosures integrally formed with the bearing surface.

[0045] Surrounding: refers to the spatial arrangement of a constraint structure, which is located around the outer periphery of the object to be supported, thus creating an obstruction on the main path of gas escape. This can be achieved in a continuous, uninterrupted ring, or in a form consisting of multiple components arranged intermittently but collectively forming a surrounding area.

[0046] The radial dimension D of the gap: the shortest horizontal distance between the inner wall of the constraint structure and the outer wall of the sheet product when the sheet product is supported by the support assembly. For example, the radial gap can range from 50 micrometers to 300 micrometers to achieve a balance between effectively constraining airflow at low flow rates and avoiding mechanical interference. This range can be further specified for sheet products of specific sizes; for example, for a sheet product with a diameter of 300 millimeters, the radial dimension of the gap can be 50 to 300 micrometers; for a sheet product with a diameter of 200 millimeters, the radial dimension of the gap can be 50 to 240 micrometers.

[0047] Constraint ring: Specifically refers to a three-dimensional structure that is annular and has a vertical or nearly vertical inner wall, as a specific implementation of a constraint structure. For example, it includes, but is not limited to, a freestanding metal ring fixed to the outer edge of the substrate bearing surface or fixed to the bearing surface by fasteners or clips; a ceramic ring fixed by adhesive or welding; or a composite material ring that can be detachably inserted into the annular mounting groove of the substrate.

[0048] Height H: This refers to the dimension by which the restraint ring protrudes upwards from the bearing surface, i.e., the vertical distance of its apex relative to the bearing surface. It is configured such that when the sheet product is air-floated to the intended working height range with its maximum expected warpage, no part of the sheet product protrudes above the apex of the restraint ring, ensuring the effectiveness of the restraint. For example, for sheet products with warpages of several thousand micrometers, the dimension of H can range from 5 mm to 7 mm.

[0049] Air flotation height: refers to the average vertical distance between the lower surface of the sheet product and the bearing surface of the substrate when the sheet product is in a stable working state.

[0050] Exemplary support components: refer to Figures 1 to 6 An embodiment of this application provides a support component 100 including a substrate 10. The substrate 10 has a bearing surface 20 for facing an object W to be supported (i.e., a thin sheet product, such as a wafer). The bearing surface 20 is provided with a plurality of vents 21, which may include vents 213 and suction holes 214. The vents 213 are used to eject gas to form a non-contact support air cushion in the space between the bearing surface 20 and the object W to be supported. The suction holes 214 are used to draw in gas to stabilize the thin sheet product located above the air cushion. The size and shape of the bearing surface 20 are not limited and can be flexibly set according to the shape of the supported object. For example, when the object W to be supported is a wafer, the bearing surface 20 can be circular.

[0051] Multiple air outlets 213 and air intakes 214 can be provided on the bearing surface 20. The spacing and number of the multiple air outlets 213 and multiple air intakes 214 can also be designed as needed, and are not specifically limited here. Of course, in the process of forming the air cushion support sheet product, it can be achieved by air jetting alone, by air suction alone, or by the combined action of air jetting and air suction.

[0052] A constraint structure 30 can be provided on the base 10. The constraint structure 30 is arranged around the outer periphery of the object to be supported, so that the object to be supported W is located inside the constraint structure 30. The constraint structure 30 has an inner sidewall 301, and a gap 302 is formed between the inner sidewall 301 and the outer sidewall 307 of the object to be supported W. In this way, the inner sidewall 301 facing the space is equivalent to forming a physical barrier on the outside of the air cushion, so that the gas cannot escape freely from the outside of the air cushion. It needs to flow radially from the center of the air cushion to the edge of the air cushion, and then turn 90 degrees and flow into the gap 302.

[0053] Thus, because the gas escape path is altered, the total flow resistance becomes the sum of the flow resistance of the radial portion of the air cushion and the flow resistance of the gap 302 portion, effectively increasing the flow resistance. Furthermore, the gas venting area decreases, and this change in venting area alters the flow field and pressure distribution within the gas. This smaller venting area causes gas to accumulate at the gap 302 (i.e., the edge of the air cushion), leading to an increase in local pressure in that area. The larger edge pressure, in turn, affects the pressure distribution of the air cushion, increasing the overall pressure curve from the center to the edge. This helps to increase the average air pressure within the air cushion, thereby helping to raise the height of the supported object with the same air supply. It also allows maintaining the same target pressure with a smaller air supply, further improving gas utilization.

[0054] Furthermore, the addition of the constraint structure 30 allows the gas to flow out through the narrow gap 302 in a more orderly and controlled manner. This not only helps maintain the internal state of the air cushion and prolongs the residence time of the gas under the sheet product, thereby increasing the pressure and stiffness of the air cushion and reducing disordered eddies and turbulence generated at the edges of the air cushion, but also helps reduce the severity of vertical fluctuations in the sheet product. This helps to quickly attenuate fluctuations and improve the stability of sheet products with large warpage, thus improving measurement accuracy and production yield. In this way, while improving the internal stability of the air cushion, the adjustment range of the external support components is further reduced, simplifying the usage method.

[0055] In summary, this application physically alters the gas flow field by adding a constraint structure 30 around the air cushion, restricting the most direct gas escape path. This forces the gas to overcome additional flow resistance introduced by the constraint structure 30 as it escapes outward, increasing the edge pressure of the air cushion and thus raising the overall average pressure of the air cushion. In this way, under the same air supply flow rate, it helps to increase the average pressure within the air cushion, thereby contributing to a higher lifting force to overcome the pressure on the sheet product. It also helps to improve gas utilization, reducing the gas flow rate required to lift the sheet product to the same height, and helps to achieve a more stable air flotation state, thus providing stable non-contact support for sheet products with large warpage to a certain extent.

[0056] In one example, the constraint structure can be set on the bearing surface and fixed to the bearing surface by plugging.

[0057] In another example, the constraint structure can be set on the outer edge of the substrate and fixed to the outer edge of the substrate by means of a slot.

[0058] Of course, there are no specific limitations on the shape, size, quantity, specific installation location, and fixing method of the constraint structure, as long as it can form a physical barrier for the air cushion.

[0059] The shape of the constraint structure 30 can include regular shapes such as circles, rectangles, and trapezoids, or it can include irregular shapes, as long as it forms a certain obstruction on the side facing the air cushion and can change the flow field and escape path of the gas in the space.

[0060] For example, the support component 100 may include one or more upright baffles or protrusions arranged circumferentially, which may be closely arranged or spaced apart to form a physical barrier, and may also include multiple regular or irregular shapes to partially enclose the space, which helps to change the flow field and escape path of the gas.

[0061] Preferably, the constraint structure 30 may include a continuous constraint ring 305 surrounding the outer periphery of the object W to be supported, which not only helps to reduce the difficulty of processing, but also helps to change the flow field and escape path of the gas to a greater extent.

[0062] Thus, the gap 302 formed between the inner wall 301 of the constraint ring 305 and the outer wall 307 of the object to be supported W can also be regarded as an annular gap. The symmetrical annular gap is conducive to forming a pressure and flow field with a certain gradient distribution, so as to further simplify the gas escape path.

[0063] Specifically, in the unconstrained support assembly 100, since the air buoyancy height h of the sheet product is much smaller than the radius R of the sheet product, the airflow flows within the narrow space between the sheet product and the bearing surface. This flow field can be simplified as axisymmetric radial flow of gas between two approximately parallel disks, typically in a laminar state. Under these conditions, the complete Navier-Stokes (NS) equations can be approximated by lubrication, thus deriving the relationship between the flow rate (Qno-wall) and the air buoyancy height h: .in, Let m be the flow rate, g be the mass of the sheet product, h be the air buoyancy height, μ be the dynamic viscosity of the fluid, and R be the radius of the circular sheet product. This formula reveals a direct proportionality between the flow rate and the cube of the air buoyancy height, which serves as a benchmark for analyzing the system performance of the unconstrained ring 305.

[0064] Based on the specific boundary conditions of the air-floating chuck (including the integral of the gas pressure at the edge of the wafer being equal to the ambient atmospheric pressure and the gas film pressure at the lower surface of the wafer being equal to the weight of the wafer itself), further solving yields: In the unconstrained support component 100, the perimeter of the gas free-escape area is 2πR (R is the radius of the circular sheet product); in the constrained model, the total length of the annular gap is 2πR.

[0065] With the setting of the restraint ring 305, the gas no longer escapes from the outer ring of the thin-film product, but escapes through the annular gap. The total flow resistance of the gas includes the radial flow resistance under the thin-film product and the flow resistance of the annular gap. The flow field model can be described and evaluated in two specific models according to the relative relationship between the radial dimension D of the gap 302 and the thickness T of the thin-film product. The evaluation process is as follows: Model 1: Parallel plate flow model. When the radial dimension D of the gap 302 is much smaller than the thickness T of the thin-film product, that is, when D << T, the annular gap can be approximated as the flow between two parallel plates. Its flow rate formula is: , substituting the specific boundary conditions of the support component, we can get: .

[0066] It can be seen that when D << T, the required gas flow rate is equal to the flow rate without the restraint structure multiplied by a coefficient less than 1. That is to say, the smaller the radial dimension D of the gap 302, the smaller the coefficient, the less the required gas flow rate, and the more obvious the role of the restraint ring 305.

[0067] Model 2: Orifice outflow model. When the ratio of the radial dimension D of the gap 302 to the thickness T of the thin-film product is greater than 0.2, that is, when D / T > 0.2, the gas does not have enough time to flow fully in the gap 302, the entrance effect is significant, and the flow model is closer to the orifice outflow model. Its flow rate formula is: , where C d is the flow coefficient, usually taking a value of about 0.6 for a thin-walled orifice; A is the discharge area of the gap 302; ρ is the gas density; ΔP is the pressure difference on both sides of the gap 302. Substituting the specific boundary conditions of the support component, we can get: .

[0068] Among them, D is the radial dimension of the gap 302, h is the air-floating height, R is the radius of the thin-film product, m is the mass of the thin-film product, ρ is the gas density, and μ is the gas viscosity.

[0069] It should be noted that for the orifice outflow model, a critical standard needs to be set. That is, when the flow rate attenuation caused by the restraint ring 305 is less than 10%, it is considered that the role of the restraint ring 305 is not obvious, and thus the critical value of the radial dimension D of the gap 302 of the restraint ring 305 is calculated. Of course, the critical standard can also be set according to different needs.

[0070] It should also be noted that the specific boundary conditions in both Model 1 and Model 2 include: the pressure at the annular gap outlet (i.e., the location where gap 302 communicates with the external atmosphere) is the ambient atmospheric pressure; the pressure at the gap 302 inlet (i.e., the junction of the wafer edge and the retaining ring) is continuous with the pressure at the radial flow end below the wafer; and the integral of the gas film pressure on the lower surface of the wafer is still equal to the wafer weight.

[0071] For example, for a 12-inch thin sheet product with a thickness T of 775 μm, a parallel plate model is used when the annular gap is less than or equal to 155 micrometers (i.e., D ≤ 155 micrometers), and an orifice outlet model is used when the annular gap is greater than 155 micrometers (i.e., D > 155 micrometers).

[0072] It should be noted that the constraint structure 30 is not a simple physical enclosure, but rather transforms the flow field from a widely dispersed and difficult-to-control surface outlet into a flow field with concentrated dispersion and controllable resistance at a narrow slit outlet. The parallel plate and orifice outflow model can provide a quantitative design tool for this flow field. Thus, when supporting thin sheet products of common sizes (such as 8-inch, 12-inch, and 18-inch), designing the gap 302 to be between 50 and 300 micrometers helps to achieve high stability support for thin sheet products with large warpage using less gas. Of course, the optimal gap size for other sizes of thin sheet products can also be calculated based on the above model; no specific limitations are made here.

[0073] Based on this, experiments were conducted to compare the air buoyancy height and flow rate Q of an unconstrained ring and a constrained ring with a radial dimension D of 150 micrometers for gap 302. Figure 16 As shown.

[0074] With an air flotation height h = 500 μm and no constraint ring, the required experimental flow rate for the support assembly is 13 L / min, and the theoretical flow rate is 15.4 L / min. With an air flotation height h = 500 μm and a radial dimension D of 150 μm for the constraint ring gap 302, the required experimental flow rate for the support assembly is 7 L / min, and the theoretical flow rate is 8.7 L / min. The theoretical attenuation is 43.5%, and the actual attenuation is 46%, which is highly consistent with the theoretical prediction.

[0075] It can be seen that the calculation results of the above parallel plate flow model and orifice outflow model correspond to the experimental results. Therefore, the above models can guide the actual design when supporting thin sheet products of different sizes.

[0076] pass Figure 17Furthermore, it can be seen that for actual products with a warpage of up to 1500μm, when using a constraint ring 305 with a radial dimension D of 100μm and a gap 302, the actual flow rate required by the support component with the constraint structure is reduced by up to 72% compared to the actual flow rate required by the support component without the constraint structure when reaching the same air float height. Moreover, the stability of the air float height is improved by more than 50% as can be seen from the change in the reading of the capacitive sensor.

[0077] By comparing the theoretical values ​​calculated by the model with the actual values, it can be seen that the above model can accurately derive the optimal radial dimension range corresponding to the gap for thin sheet products of different sizes and thicknesses. Furthermore, within the optimal radial dimension range, the constraint structure 30 can guide the flow resistance transfer and concentrate it into a controllable narrow gap, forcing the gas to do work more effectively below the thin sheet product, thereby achieving stable and uniform support for the large warp thin sheet product with extremely low flow rate.

[0078] Based on the above formula, the radial dimension D of the gap 302 satisfies: D≥50μm, which helps to avoid friction and collision between the sheet product and the constraint structure 30 during loading or dynamic floating, thereby helping to improve the safety of the sheet product support.

[0079] Of course, an excessively large gap 302 will not provide adequate constraint; the specific upper limit can be calculated based on the different sizes of wafer products and models. Based on fluid dynamics analysis and experimental verification, for a typical 300 mm diameter wafer, the radial dimension D of the gap 302 can be set between 50 micrometers and 300 micrometers. Within this range, it not only helps to constrain airflow but also helps to avoid mechanical interference.

[0080] Specifically, for common-sized sheet products, such as 8-inch sheet products, the radial dimension D of the theoretical gap 302 between the inner wall 301 of the constraint ring 305 and the outer wall 307 of the sheet product satisfies: 50 micrometers ≤ D ≤ 240 micrometers; for 12-inch sheet products, the radial dimension D of the theoretical gap 302 between the inner wall 301 of the constraint ring 305 and the outer wall 307 of the sheet product satisfies: 50 micrometers ≤ D ≤ 300 micrometers; and for 18-inch sheet products, the radial dimension D of the theoretical gap 302 between the inner wall 301 of the constraint ring 305 and the outer wall 307 of the sheet product satisfies: 50 micrometers ≤ D ≤ 350 micrometers. This not only helps improve gas utilization but also enhances the stability of the support for sheet products with large warpage.

[0081] It should be noted that, within the above range, compared with support components without constraint rings, the required flow rate for the same air flotation height of the sheet product can be reduced by more than 10%, and the air flotation stability can be improved by at least 10%. For example, for an 8-inch sheet product, if D < 50μm, the sheet product is prone to contact with the constraint ring during loading and unloading, which may lead to risks such as particulate contamination or mechanical damage; if D > 240μm, the attenuation effect of the constraint ring on the airflow will be significantly weakened, and its constraint and stability improvement effect on the flow field will be less than 10%. Therefore, the radial dimension of the gap 302 directly affects the final stability of the air flotation support.

[0082] The height H of the constraint structure 30 protruding upward from the bearing surface 20 is configured such that when the part of the object to be supported W with the greatest warping is supported to the working height by the air cushion, no part of the object to be supported is higher than the top of the constraint structure 30. In this way, the support assembly helps to ensure that gas can only or mainly escape through the gap 302 during the support of the sheet product, thereby helping to prevent gas from escaping unrestrainedly from the top of the sheet product and causing pressure leakage of the air cushion.

[0083] Furthermore, the upward protrusion height H of the constraint structure 30 can satisfy: 5mm ≤ H ≤ 7mm. This ensures that the sheet product is located inside the constraint structure 30 while also helping to reduce friction and contact during the loading process. Of course, the upward protrusion height H of the constraint structure 30 can also be flexibly designed according to the actual support conditions.

[0084] The height of the constraint ring 305 must ensure that the air-float product does not exceed the upper surface of the constraint ring 305 after air-floatation, while not affecting the loading, unloading, and subsequent measurement operations of the air-float product. Therefore, for air-float products with a warpage of less than 4000 μm, the air-floatation constraint ring 305 needs to protrude approximately 5 mm to 7 mm from the chuck surface. Furthermore, to accommodate the needs of different air-float products, the constraint ring 305 can be made of various materials, such as metals, ceramics, and polymer composites. By appropriately setting the gap 302 between the constraint ring 305 and the air-float product, the goal of air-floatating air-float products with large warpage can be achieved at low flow rates, improving the measurement accuracy of the air-float product.

[0085] It should be noted that the support components provided in this application are applicable to sheet products with a warpage of no more than 4000 micrometers. Of course, sheet products with a greater warpage need to be further calculated and judged according to different models to determine whether they can be stably supported.

[0086] It is understood that multiple mounting slots can be provided on the substrate, and the constraint structure 30 can be detachably mounted on the substrate 10. For example, the substrate may have a ring-shaped mounting slot or multiple corresponding mounting slots for the constraint structure 30 on the surface or outer edge of the bearing surface 20. Correspondingly, the bottom of the constraint ring 305 is provided with a matching flange or snap-fit ​​structure. The multiple mounting slots are located at different distances from the center of the substrate to install constraint rings 305 with different inner diameters. In this way, constraint rings 305 with different inner diameters are installed in different ring-shaped mounting slots, allowing the same support component to be quickly and reliably applied to support thin wafer products of different sizes, which helps to improve the versatility and applicability of the support component. For example, 8-inch (200 mm), 12-inch (300 mm), or 18-inch (450 mm) wafers.

[0087] In one example, the support component may include a plurality of constraint structures 30 symmetrically arranged. For example, when the object to be supported is a circular structure (such as a wafer), a plurality of symmetrically arranged arc structures are arranged around the wafer.

[0088] Combination Figures 2 to 6 A preferred internal configuration of the matrix is ​​described in detail, but of course, the internal structure of the matrix is ​​not limited to this.

[0089] One embodiment of this application provides a substrate 10 that may include a composite structure formed by stacking multiple discs to achieve precise control of airflow. The substrate 10 may include an airflow channel that communicates with multiple air outlets 213 and multiple air intakes 214, allowing different air outlets to eject and / or draw in gases of different or the same flow rate. The airflow channel may be disposed inside the air outlet disc 12, and the upper surface of the air outlet disc 12 may serve as a bearing surface 20. The surface of the air outlet disc 12 may be provided with multiple air outlets for ejecting gas, which may communicate with the airflow channel. The size, arrangement order, and shape of the air outlets are not specifically limited.

[0090] Preferably, the multiple air outlets and air inlets are arranged in a multi-ring concentric array, which helps to form a more uniform and stable air cushion.

[0091] Optionally, multiple air outlets and air inlets are spaced apart (see reference). Figure 1 ).

[0092] The base 10 may further include a pressure stabilizing disc 13, which has a large-volume first chamber 131 inside. The first chamber 131 is used for preliminary pressure stabilization and buffering of the airflow to smooth out pressure pulsations or instantaneous fluctuations caused by the air supply system during the input process, providing a relatively stable input condition for subsequent fine airflow distribution. The pressure stabilizing disc 13 may be located below the outlet disc 12. The air supply system may include a first air passage and a second air passage, the details of which are described below and will not be elaborated here.

[0093] The support assembly 100 may also include a control assembly, which may include a pressure control unit 161 and a flow control unit 165. The pressure control unit 161 is connected to the flow control unit 165, and the flow control unit 165 is connected to the airflow channel so that the smooth airflow after multiple layers of adjustment and control is finally sprayed vertically and uniformly from the bearing surface 20.

[0094] The flow control unit 165 may include a flow equalization disc 14 and a throttling disc 15. The flow equalization disc 14 may include multiple throttling orifices 141 and multiple flow distribution channels 142. The flow distribution channels 142 are used to receive airflow from the throttling orifices 141 provided on the throttling disc 15, equalize the airflow, and directionally distribute it to specific areas of the bearing surface 20 to ensure that the airflow is macroscopically uniformly distributed. The throttling disc 15 may be located between the outlet disc 12 and the pressure stabilizing disc 13.

[0095] refer to Figures 7 to 13 The airflow from the first chamber 131 is first throttled through the throttling orifice 141, resulting in initial pressure drop and flow distribution. Subsequently, the airflow enters the diversion channel 142. The overall layout of the diversion channel 142 can take various forms, such as radial, grid, or concentric ring patterns, or it can be arc-shaped, straight, zigzag, annular, or wavy. The cross-sectional shape of the diversion channel 142 can be triangular, rectangular, semi-circular, or trapezoidal, with a channel width between 1.2 mm and 2 mm, and a channel depth between 0.3 mm and 1 mm.

[0096] By combining and matching the above-mentioned flow channel morphology, cross-sectional shape and structural dimensions, the flow equalization disk can adapt to various application scenarios and achieve precise and controllable distribution of airflow to meet different flow rate and pressure drop requirements.

[0097] The throttling disc 15 can be positioned above the flow equalization disc 14. The throttling disc 15 may include finer throttling channels with orifices smaller than the upstream diversion channel 142, performing secondary throttling on the airflow to further precisely control the flow balance to each outlet. By designing the length, orifice diameter, and distribution of the throttling channels, the unevenness of the upstream pressure distribution can be effectively suppressed, ensuring that the airflow pressure reaching all inlets of the outlet disc 12 is highly consistent.

[0098] The throttling disc 15 may also include a second chamber 132 for receiving airflow from another independent air source, achieving functional isolation. Furthermore, by employing variable-diameter stepped orifices as throttling channels, the throttling disc 15 creates a controllable pressure drop within the flow channel through a stepped orifice diameter, thereby achieving precise control over the airflow resistance of each branch flow path. Optimizing parameters such as the orifice diameter ratio, number of steps, channel length, and spatial layout of the throttling channel helps suppress upstream pressure fluctuations, improving the pressure balance and dynamic stability of the outflow, thus providing a reliable guarantee for the final formation of a uniform air cushion.

[0099] The pressure control unit 161 may include a positive pressure control unit 162 and a negative pressure control unit 163. The positive pressure control unit 162 is connected to a first chamber 131, which is connected to a first air nozzle 211 of a plurality of air outlets 213 to form a first air path (i.e., airflow path). The negative pressure control unit 163 is connected to a second chamber 132, which is connected to a second air nozzle 212 of a plurality of air intakes 214 to form a second air path (i.e., airflow path). The positive pressure control unit 162 is used to adjust the airflow rate or airflow pressure parameters in real time so that the gas ejected from the air outlets forms an air cushion, thereby supporting the sheet product to the target height. The negative pressure control unit 163 is used to precisely control the airflow rate or airflow pressure parameters to suppress large fluctuations in the sheet product, so that the sheet product is stably supported at the target height, thereby improving the stability of the support process.

[0100] In this way, the airflow passes through the throttling channel and the diversion channel 142, then through the first air nozzle 211 and the second air nozzle 212, and finally forms an air cushion at the bottom of the sheet product. Excess gas can only escape through the narrow gap 302 between the outer sidewall 307 of the sheet product and the inner sidewall 301 of the constraint structure 30, which helps to ensure that a stable air cushion is quickly formed with a small flow rate to support the sheet product.

[0101] refer to Figure 1 The support assembly may also include lifting pins 17 and support frames. The lifting pins 17 can load the sheet product by moving up and down. By adjusting the height of the lifting pins 17, four lifting pins 17 are evenly arranged around the outer circumference of the sheet product to load the sheet product without friction against the support assembly. When the sheet product is supported by the air cushion, the lifting pins 17 descend into the base, thus avoiding friction with the sheet product. For example, the support frame may include a floating support frame 18 and fixed support frames 181. One floating support frame 18 and two fixed support frames 181 are arranged at 120° intervals around the outer circumference of the sheet product to ensure the sheet product is aligned and improve stability during air flotation. The lifting pins 17 and support frames can be located inside the constraint structure 30 on the bearing surface 20.

[0102] It should be noted that the floating support frame 18 and the fixed support frame 181 can be tangent to the outer side of the sheet product, and the fixed support frame 181 is fixed in position to position the sheet product in the horizontal direction. The floating support frame 18 provides support (such as elastic support, resting against the sheet product without clamping) during actual use (e.g., measurement) and is released when loading and unloading the sheet product to ensure the three positions of the sheet product are positioned in the horizontal direction.

[0103] The support assembly 100 may also include a height sensor 19, which monitors the air buoyancy height and fluctuation value of the wafer in real time during the transfer of the wafer (such as a wafer) to the support assembly and the generation of air cushion support, and provides feedback to the control assembly. For example, the height sensor 19 may be a capacitive sensor 191. For example, the height sensor 19 may be located at the middle of the support surface to accurately obtain the air buoyancy height and fluctuation value of the wafer.

[0104] Example of how to use the support component: For instructions on using the support component 100 (such as the testing process), please refer to the attached document. Figure 14 The specific steps are as follows: S10, start the system and preset the pressure parameters (including positive and negative pressure parameters) of the pressure control unit according to the degree of warping of the sheet product.

[0105] S20, for loading thin sheet products.

[0106] The sheet product is loaded together by lifting pin 17, floating support frame 18, and fixed support frame 181. The height of lifting pin 17 and floating support frame 18 is adjustable and not limited in specific dimensions.

[0107] The floating support frame 18 and the fixed support frame 181 can be used for real-time positioning of sheet products in the horizontal direction.

[0108] The thin sheet product is monitored in real time in the vertical direction by a height sensor 19 (such as a capacitive sensor 191). After the presence of the thin sheet product is detected, its air flotation height and fluctuation range are continuously monitored.

[0109] S30, Adjust the pressure control unit to stabilize the sheet product. By adjusting the positive pressure parameter of the positive pressure control unit, the air flotation height of the sheet product is brought into the preset target range; by adjusting the negative pressure parameter of the negative pressure control unit, height fluctuations are suppressed to meet the threshold requirements. After multiple coordinated adjustments of the positive and negative pressure parameters, when both the height and fluctuations of the sheet product are controlled within the allowable range, it is determined that a stable state has been reached.

[0110] S40, maintain the current flow, and you can start the subsequent measurement process.

[0111] S50, after the measurement is completed, the sheet product can be unloaded again by the lifting pin 17, the floating support frame 18 and the fixed support frame 181.

[0112] The specific unloading process is similar to the loading process for sheet products, and will not be described in detail here.

[0113] Exemplary measuring devices, wafer transfer equipment, thin film deposition equipment, or photolithography equipment: refer to Figure 15 Based on the aforementioned support component 100, one embodiment of this application also provides a measuring device 200. The measuring device 200 may include the support component 100 and a measuring unit 210. The measuring unit 210 is used to perform measurements while the object to be tested is supported by the support component 100, such as measuring parameters like the morphology, thickness, and warpage of a wafer with high warpage. No specific limitations are made here. The support component 100 can be any of the exemplary support components 100 described above, and will not be elaborated upon here.

[0114] In addition, based on the above-mentioned support component 100, an embodiment of this application also provides a wafer transfer device. The wafer transfer device may include the support component 100 and a robot arm. The robot arm is used to transport the wafer from the support component 100. The support component 100 may be any of the above-mentioned exemplary support components 100 structures, which will not be described in detail here.

[0115] Based on the aforementioned support component 100, an embodiment of this application also provides a thin film deposition apparatus. The thin film deposition apparatus may include a deposition chamber and a support component 100 located in the deposition chamber. The deposition chamber is used to perform thin film deposition on the supported wafer. The support component 100 may be any of the above-described exemplary support components 100 structures, which will not be described in detail here.

[0116] Based on the aforementioned support component 100, one embodiment of this application also provides a photolithography apparatus. The photolithography apparatus may include the support component 100 and an optical system. The optical system is used to perform photolithography on the supported wafer. The support component 100 may be any of the above-described exemplary support components 100 structures, which will not be described in detail here.

[0117] Of course, the support component 100 can be used in any scenario that requires support for sheet products, and no specific limitations are made here.

[0118] In addition, each functional unit or module in the various embodiments of this application can be integrated into one processing unit or module, or each unit or module can exist physically separately, or two or more units or modules can be integrated into one unit or module.

[0119] It is understood that in this application, directional descriptions such as "upper," "lower," "inner," and "outer" are relative rather than absolute. These directional terms may be applicable when the support components provided in this application are positioned according to the posture and location shown in the accompanying drawings.

[0120] It should be understood that although terms such as “first” or “second” may be used in this application to describe various elements (such as the first chamber and the second chamber), these elements are not defined by these terms, which are only used to distinguish one element from another.

[0121] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0122] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

[0123] The components and devices described in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the accompanying drawings. As those skilled in the art will recognize, these components and devices can be connected, arranged, and configured in any manner.

[0124] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A support component, characterized in that, include: The substrate has a bearing surface and a plurality of air holes are provided on the bearing surface. The plurality of air holes are used to eject gas to form an air cushion that supports the object to be supported. The air cushion is located in the space between the bearing surface and the object to be supported. A constraint structure is disposed on the substrate and surrounds the outer periphery of the object to be supported. The constraint structure has an inner sidewall, and a gap is formed between the inner sidewall and the outer sidewall of the object to be supported. The gap is used to change the flow field and escape path of the gas to reduce the gas from the space to the outer periphery.

2. The support component according to claim 1, characterized in that, The radial dimension D of the gap satisfies: D ≥ 50 μm.

3. The support component according to claim 1, characterized in that, When the size of the object to be supported is 8 inches, the radial dimension D of the gap satisfies: 50 μm ≤ D ≤ 240 μm; When the size of the object to be supported is 12 inches, the radial dimension D of the gap satisfies: 50 μm ≤ D ≤ 300 μm; When the size of the object to be supported is 18 inches, the radial dimension D of the gap satisfies: 50 μm ≤ D ≤ 350 μm.

4. The support component according to claim 1, characterized in that, The constraint structure is installed in a slot provided on the base.

5. The support component according to claim 1, characterized in that, The height H of the constraint structure protruding upward from the bearing surface is configured such that when the part of the object to be supported with the greatest warping is supported to the working height by the air cushion, no part of the object to be supported is higher than the top of the constraint structure.

6. The support component according to claim 5, characterized in that, The height H of the upward protrusion of the constraint structure satisfies: 5mm≤H≤7mm.

7. The support component according to claim 6, characterized in that, The substrate has multiple mounting slots, which are located at different distances from the center of the substrate and are used to install constraint rings with different inner diameters.

8. The support component according to claim 1, characterized in that, The constraint structure includes a continuous constraint ring surrounding the outer periphery of the object to be supported.

9. The support component according to claim 1, characterized in that, The support component includes multiple constraint structures, which are symmetrically arranged.

10. The support component according to claim 1, characterized in that, The substrate includes an airflow channel that communicates with the plurality of air holes, so that different air holes eject gas at the same or different flow rates. The substrate also includes a pressure control unit and a flow control unit, the pressure control unit being connected to the flow control unit, and the flow control unit being connected to the airflow channel. The pressure control unit includes a pressure stabilizing disc, and the flow control unit includes a flow equalization disc and a flow throttling disc. The flow equalization disc consists of multiple throttling orifices and multiple flow distribution channels. The flow distribution channels are used to receive gas from the throttling orifices provided in the flow throttling disc.

11. The support component according to claim 10, characterized in that, The multiple diversion channels are all shaped like an arc, a straight line, a broken line, a ring, or a wave, and the cross-sectional shape of the multiple diversion channels is one of a triangle, a rectangle, or a semicircle. The pressure stabilizing plate includes a first chamber, which is used to connect to the gas supply system and the flow equalization plate.

12. The support component according to claim 1, characterized in that, The object to be supported includes a sheet product.

13. A measuring device, characterized in that, include: The support assembly and measuring unit as described in any one of claims 1 to 12, wherein the measuring unit is configured to perform a measurement while the object to be tested is supported by the support assembly.

Images