Air floating sheet supporting table

Abstract

The application discloses a kind of air float bearing table, belong to semiconductor wafer bearing equipment field, including two kinds of whole machine implementation structure: three layers split type gas-liquid adapter structure, multi-layer superimposed flow distribution pad structure;Core components include air float disc, gas-liquid distribution assembly, constant-temperature heat exchange runner.Gas-liquid distribution assembly is layered to transport positive pressure, vacuum, pressure relief gas, and circulating fluid passage is integrated in gas-liquid adapter disc or air float disc back, and the whole constant temperature of air float disc is preformed, and constant-temperature positive pressure gas is sprayed to form support air film, realize wafer non-contact suspension bearing and global precision temperature control.The support stiffness of the application can be adapted to different wafer warping degrees, eliminate wafer deformation problems caused by rigid suction cup, temperature control uniformity is excellent, provide two kinds of interchangeable whole machine structure, suitable for semiconductor lithography, detection, coating and other high-precision process scenarios.

Description

Technical Field

[0001] This invention relates to the field of semiconductor wafer carrier equipment technology, and is particularly applicable to wafer carrier and temperature control devices for 8-inch and 12-inch semiconductor wafer photolithography, inspection, coating and other process stations, specifically an air-floating wafer carrier stage. Background Technology

[0002] In semiconductor wafer fabrication, the wafer carrier directly determines the wafer surface accuracy, temperature uniformity, and process yield. Currently, the mainstream wafer carrier in the industry uses a rigid chuck vacuum adsorption solution, where the entire wafer is bonded to the surface of the metal chuck, which has the following inherent drawbacks: Rigid hard contact adsorption can easily cause wafer edge warping, local stress deformation of thin wafers, insufficient bonding of wafers with large warping, and difficulty in meeting the flatness index of high-precision process requirements. 1. Vacuum full-bonding heat exchange relies on solid-to-solid contact heat conduction. Differences in the bonding gaps between parts of the wafer can lead to uneven temperature distribution and poor temperature control accuracy across the entire wafer area. 2. The single suction cup structure is only compatible with fixed-size wafers and cannot be used with the two mainstream wafer sizes of 8-inch and 12-inch, resulting in poor equipment versatility. 3. Existing air-floating wafer support stages only achieve wafer levitation support, lacking an integrated and precise temperature control structure, and cannot simultaneously complete wafer levitation support and global constant temperature control; at the same time, the air-floating support has a single stiffness, which cannot adapt to both conventional flat wafers and large-deformation warped wafers, thus limiting the applicable scenarios of the equipment. Based on the above-mentioned shortcomings of the existing technology, this invention proposes an air-floating wafer support stage that is compatible with multi-size wafers, has dual-stiffness air-floating support, and integrated liquid-cooled constant temperature control. Summary of the Invention

[0003] The purpose of this invention is to provide an air-bearing wafer support stage that can solve at least one of the technical problems of existing rigid vacuum chucks, such as easy wafer deformation, poor temperature control accuracy, weak wafer size compatibility, and unadjustable air-bearing support stiffness.

[0004] The technical solution of this invention is implemented as follows: Option 1: An air-float wafer support stage, comprising an air-float disk, a gas-liquid transfer disk, and a distribution disk assembled sequentially from top to bottom; the upper surface of the air-float disk is provided with multiple concentrically arranged air-float islands as air-float support units, and the air-float islands integrate positive pressure micro-holes, vacuum adsorption holes, and atmospheric connection holes; the positive pressure micro-holes output clean positive pressure gas to form a supporting gas film between the wafer and the air-float disk to achieve wafer suspension and support, the vacuum adsorption holes output negative pressure to constrain the wafer's planar position, and the atmospheric connection holes cooperate with grooves to complete gas film depressurization and exhaust; the air-float disk is provided with multiple layers of interconnected annular grooves to achieve parallel conduction of positive pressure and vacuum channels in the same ring of air-float islands; the air-float disk has annular grooves adapted to the edge warping deformation of 8-inch and 12-inch wafers, and different numbers of air-float islands can be used in different areas to match the corresponding size wafers; the air-float disk can be equipped with high-rigidity islands, low-rigidity islands, or a mixture of both, or the independent islands can be eliminated and a densely distributed microporous integrated reinforced support structure can be used to adapt to large deformation wafers. The gas-liquid transfer plate is fitted onto the lower surface of the air flotation plate, with an internal circulating liquid channel. A constant-temperature liquid supply device connects to the external liquid channel, introducing a circulating constant-temperature fluid. The gas-liquid transfer plate conducts heat with the air flotation plate surface, maintaining a constant temperature for the entire air flotation plate. The gas flowing through the positive pressure micro-holes is simultaneously pre-temperature controlled. The supporting gas film formed by the constant-temperature gas serves both load-bearing and heat exchange functions, achieving non-contact precise temperature control of the wafer. Positive pressure, vacuum, and atmospheric passage interfaces are provided on the side wall of the gas-liquid transfer plate, respectively connecting to the lower distribution plate. The distribution plate is fitted onto the bottom of the gas-liquid transfer plate, with independent positive pressure distribution connecting holes, vacuum distribution connecting holes, and exhaust distribution connecting holes, corresponding to the various passage interfaces of the gas-liquid transfer plate, enabling independent stratified distribution and delivery of positive pressure gas, negative pressure vacuum, and depressurized atmosphere. The upper surface of the distribution plate is a sealed bonding surface, sealing the liquid channel at the bottom of the gas-liquid transfer plate to prevent leakage of the constant-temperature fluid.

[0005] Option 2: An air-float wafer support stage, comprising an air-float disk and a multi-layer stacked distribution assembly; the multi-layer stacked distribution assembly consists of a distribution pad, a gas path adapter plate, and a distribution disk stacked and sealed in sequence; the upper surface of the air-float disk is arranged with multiple concentric air-float island pads, and the lower surface of the air-float disk directly opens a liquid circulation channel to introduce a constant-temperature fluid to achieve uniform temperature of the disk; the air-float island pads are selected from high-rigidity and low-rigidity island pads, arranged individually or in combination; the distribution pad and the gas path adapter plate are both provided with through-holes connecting positive pressure, vacuum, and atmosphere, and the distribution disk is provided with an annular distribution groove and independent positive pressure, vacuum, and exhaust connection holes; the multi-layer distribution assembly distributes and delivers the gases in stages, and the air-float disk suspends and supports the wafer through a constant-temperature gas film and simultaneously completes the global temperature regulation of the wafer.

[0006] Furthermore, the air-floating island pads are divided into two categories: high-rigidity island pads, in which the island pad grooves and positive pressure micro-holes are arranged tangentially at intervals, resulting in a slow exhaust rate and high air film support stiffness, suitable for flat wafers; and low-rigidity island pads, in which the island pad grooves and positive pressure micro-holes are arranged concentrically, resulting in a fast exhaust rate and low air film support stiffness, suitable for slightly warped wafers.

[0007] Furthermore, the integrated reinforced support structure eliminates the independent air-floating island pad, and is densely covered with multiple sets of positive pressure micro-holes in concentric layers. It is equipped with vacuum ring grooves, multi-stage exhaust ring grooves and connecting holes, which greatly increases the number of micro-holes and significantly enhances the support stiffness, making it suitable for large deformation warped wafers.

[0008] Furthermore, the internal liquid channel of the gas-liquid transfer plate adopts any one or a combination of spiral, star-shaped, and U-shaped flow channels; the constant temperature fluid adopts circulating pure water or heat transfer oil.

[0009] Furthermore, the air-floating disk and air-floating island pads are arranged concentrically in three rings: 10 in the first ring, 16 in the second ring, and 24 in the third ring. Only the first and second rings are used to adapt to 8-inch wafers, while all three rings are used simultaneously to adapt to 12-inch wafers.

[0010] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses air film suspension bearing to replace the traditional rigid vacuum chuck, and the wafer is held without rigid contact, which greatly reduces the wafer holding stress, avoids deformation and damage to thin and warped wafers, and improves the wafer surface accuracy. 2. Integrated liquid-cooled constant temperature heat exchange structure, the entire air float is pre-cooled / preheated by constant temperature fluid, and the positive pressure gas forms a heat exchange gas film after being kept at a constant temperature by the disk. High-precision and uniform temperature control of the wafer is achieved by relying on the full-domain contact heat exchange of the gas. The temperature control consistency is far superior to solid contact heat conduction. 3. The air-floating island pad can be activated in a controlled manner in zones. One set of equipment is compatible with two mainstream wafer specifications, 8-inch and 12-inch, reducing equipment procurement and modification costs. 4. Two complete assembly solutions are provided: a three-layer split gas-liquid transfer structure and a multi-layer distribution pad stacked structure. The gas and liquid paths are independently distributed in layers, and the gas and liquid are completely isolated to avoid fluid contamination of the wafer process surface. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is an exploded view of the overall assembly of the three-layer split air-bearing support platform according to Embodiment 1 of the present invention; Figure 2 This is a top view of the overall structure of the air-floating disc of the present invention; Figure 3 This is a schematic diagram of the high-rigidity air-floating island pad structure of the present invention; Figure 4This is a schematic diagram of the low-rigidity air-floating island pad structure of the present invention; Figure 5 This is a schematic diagram of the island-free integrated reinforced support air-floating disc structure of the present invention; Figure 6 This is a schematic diagram of the flow channel structure of the gas-liquid transfer plate of the present invention; Figure 7 This is a schematic diagram of the distribution disk structure of the present invention; Figure 8 This is an exploded view of the multi-layer stacked distribution pad type air flotation support platform according to Embodiment 2 of the present invention. Figure 9 This is a schematic diagram of the liquid channel on the back of the air flotation disk in Embodiment 2 of the present invention; Figure 10 This is a schematic diagram of the internal distribution groove structure of the distribution plate in Embodiment 2 of the present invention.

[0013] Figure label: 1-Air flotation plate; 2-Gas-liquid transfer plate; 3-Distribution plate; 2.1 - Positive pressure microvia; 2.2, 2.6, 2.10 - Atmospheric connection vias; 2.3, 2.7, 2.9 - Interconnecting slots for atmospheric connection vias; 2.4 - Positive pressure atmospheric connection trench; 2.5 - Vacuum adsorption vias; 2.8 - Annular grooves 2.8 adapted for edge warping of 8-inch wafers; 2.10 - Annular grooves 2.8 adapted for edge warping of 12-inch wafers; 3.1-Positive pressure hole; 3.2-Vacuum adsorption hole; 3.3-Tangential island pad groove; 3.4-Atmospheric connection hole groove; 3.5-Atmospheric connection hole; 4.1-Positive pressure hole; 4.2-Vacuum adsorption hole; 4.3-Concentric island pad groove; 4.4-Atmospheric connection hole; 4.5-Atmospheric connection trench; 5.1, 5.2, 5.3, 5.4 - Positive pressure micro-holes; 5.5, 5.6 - Vacuum ring grooves; 5.7, 5.8, 5.9 - Exhaust ring grooves; 6.1 - Liquid passage; 6.2, 6.3, 6.4 - Positive pressure passage interface; 6.5, 6.6 - Vacuum passage interface; 6.7 - Atmospheric connection interface; 7.1 - Positive pressure distribution connecting hole; 7.2 - Vacuum distribution connecting hole; 7.3 - Exhaust distribution connecting hole; 7.4 - Sealing mating surface; 8.1-Air flotation plate; 8.2-Distribution pad; 8.3-Gas transfer plate; 8.5-Distribution plate; 9.1-Rear liquid channel; 10.1, 10.2, 10.3 - Distribution channel; 10.4 - Vacuum connection hole; 10.5 - Exhaust connection hole; 10.6 - Positive pressure connection hole. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0015] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0016] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0017] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0018] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0019] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" 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.

[0020] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0021] This invention provides two complete embodiments: Embodiment 1 is a three-layer split gas-liquid transfer air-float support platform, and Embodiment 2 is a multi-layer stacked distribution pad type air-float support platform; at the same time, it provides a complete and detailed description of the three types of support structures of the air-float disk, gas-liquid heat exchange, gas path distribution, and wafer adaptation method.

[0022] Example 1: Three-layer split air flotation support platform like Figure 1 As shown, in this embodiment, the entire machine is assembled from top to bottom as follows: air flotation plate 1, gas-liquid transfer plate 2, and distribution plate 3. The three are fitted together and sealed, and the gas path and liquid path are set up independently in layers to achieve complete gas-liquid isolation.

[0023] Detailed structure of the air flotation disc: like Figure 2 The upper surface of the air-floating disk 1 is concentrically arranged with three rings of air-floating island pads, with the number of zones as follows: 10 island pads in the first ring, 16 island pads in the second ring, and 24 island pads in the third ring. The three rings are independently controllable for ventilation. When only the first and second rings are activated, the support area matches the 8-inch wafer, and the disk body has annular grooves 2.8 adapted to the edge warping deformation of the 8-inch wafer to compensate for the edge deformation of the wafer. When the three rings are activated simultaneously, the support range covers the 12-inch wafer, and the annular grooves 2.10 adapted to the edge warping deformation of the 12-inch wafer participate in deformation compensation simultaneously.

[0024] A single air-floating island pad integrates three types of core channels: positive pressure micro-holes 2.1, vacuum adsorption holes 2.5, and atmospheric connection holes 2.2 / 2.6 / 2.10; it is equipped with atmospheric connection hole interconnection grooves 2.3 and 2.9 and positive pressure connection atmospheric grooves 2.4 and 2.7, which are used to quickly discharge excess gas from the air film and balance the air film pressure.

[0025] The air flotation disk is internally machined with multiple interconnected annular grooves: the positive pressure micro-holes of all air flotation island pads in the same ring are connected to the positive pressure annular grooves to achieve uniform distribution of positive pressure gas in the same ring; the vacuum adsorption holes are connected to the vacuum annular grooves to ensure consistent negative pressure constraint force throughout the wafer; the exhaust connecting holes are arranged at intervals or correspond one-to-one with the island pads, respectively connecting to the atmospheric passage of the lower gas-liquid transfer disk.

[0026] In this embodiment, three arrangement schemes can be selected for the air-floating island mat: Option A: Use high-rigidity island mats throughout ( Figure 3 The island pad groove 3.3 is tangent to the positive pressure hole 3.1 and has a reserved gap. It has high gas discharge resistance, slow exhaust rate, and high gas film equivalent stiffness. It is suitable for standard wafers with flat surfaces and no obvious warping. The island pad is integrated with vacuum adsorption hole 3.2, atmospheric connection hole 3.5, and atmospheric connection hole groove 3.4.

[0027] Option B: Use low-stiffness island pads throughout ( Figure 4 The island pad groove 4.3 and the positive pressure hole 4.1 are arranged concentrically around each other, with a large gas flow cross-sectional area, fast exhaust speed, and low gas film stiffness, which can adapt to slight wafer warping and reduce local wafer stress; it is equipped with vacuum adsorption hole 4.2, atmospheric connection hole 4.4, and atmospheric connection trench 4.5.

[0028] Option C: A mixed arrangement of high and low stiffness island pads; high stiffness island pads are arranged in the central area of ​​the wafer to ensure the flatness of the support, while low stiffness island pads are arranged at the edge of the wafer to adapt to edge warping, taking into account both support accuracy and deformation compatibility.

[0029] As an alternative support structure for air-flotation discs, such as Figure 5 It eliminates the need for all independent air-floating island pads and adopts an integrated, densely packed microporous reinforced support structure: 90 positive pressure micropores (5.1, 5.2) and 50 positive pressure micropores (5.3, 5.4) are arranged concentrically in layers, with a much higher number of micropores than the island pad solution, significantly increasing the support point density; it is equipped with vacuum ring grooves (5.5, 5.6) and three-stage exhaust ring grooves (5.7, 5.8, 5.9), which provide uniform air supply at multiple points to form an ultra-high rigidity support air film, specifically designed to support wafers with large deformation and severe warping.

[0030] Gas-liquid transfer plate structure and constant temperature heat exchange principle: like Figure 6 The gas-liquid transfer plate 2 is sandwiched between the air flotation plate 1 and the distribution plate 3, and undertakes the triple functions of gas-liquid isolation, heat conduction and gas transfer.

[0031] The tray has a circulating liquid channel 6.1, which is spiral in shape, but can also be replaced by a star shape or a back shape. The circulating liquid channel is connected to an external constant temperature liquid supply device, and a constant temperature circulating fluid is introduced into the channel. The fluid can be pure water or heat transfer oil, which can be flexibly switched according to the process temperature control range.

[0032] The upper surface of the gas-liquid transfer plate is completely in contact with the lower surface of the air flotation plate. Efficient heat conduction is achieved through metal-to-metal contact, keeping the entire air flotation plate at a constant temperature consistent with the circulating fluid. The positive pressure gas of the clean process is transported upward from the distribution plate, passes through the gas-liquid transfer plate passage and enters the positive pressure micro-hole of the air flotation plate. The gas is kept at a constant temperature by the plate body as it flows through the internal channel of the air flotation plate, and finally sprays out to form a constant temperature support gas film.

[0033] The gas-liquid transfer panel integrates multiple independent interfaces on its sidewall: positive pressure access interfaces 6.2, 6.3, and 6.4 correspond to the positive pressure supply of the three-ring air-floating island pads, enabling 8 / 12-inch zoned air supply control; vacuum access interfaces 6.5 and 6.6 deliver negative pressure vacuum; and atmospheric connection interface 6.7 connects to the outside atmosphere for gas film depressurization and exhaust. All interfaces vertically penetrate the panel body, with the bottom connecting to the corresponding distribution channels on the distribution plate.

[0034] Distribution disk structure and gas distribution logic: like Figure 7 The distribution plate 3 is located at the bottom of the whole machine and is the main air distribution unit of the whole machine.

[0035] The interior has three types of independent through-holes: positive pressure distribution through-hole 7.1, vacuum distribution through-hole 7.2, and exhaust distribution through-hole 7.3, which are connected one-to-one with the positive pressure passage interface, vacuum passage interface, and atmospheric passage interface (exhaust interface) of the gas-liquid transfer plate, respectively, so as to realize the independent layered delivery of each gas, without the risk of cross-flow or leakage.

[0036] The upper surface of the distribution plate is a high-precision flat sealing surface 7.4, which fits tightly against the bottom surface of the gas-liquid transfer plate, completely sealing the lower side of the circulating liquid channel of the gas-liquid transfer plate and preventing the constant-temperature fluid from leaking downwards and contaminating the gas circuit components. External gas sources, vacuum generators, and atmospheric pressure relief pipelines are all connected to the bottom of the distribution plate to complete centralized gas distribution.

[0037] Overall machine workflow: 1. Temperature pre-adjustment: Start the temperature-controlled liquid supply device and introduce the set temperature circulating fluid into the circulating liquid channel of the gas-liquid transfer plate. Continuous circulation and heat exchange will make the gas-liquid transfer plate and the air flotation plate reach the process target temperature as a whole. 2. Size-matched gas supply: Select the number of gas supply rings according to the wafer specifications. For 8-inch wafers, only the first and second rings of positive pressure and vacuum paths are connected; for 12-inch wafers, all three rings of paths are connected. Air flotation support molding: Positive pressure gas is delivered to the positive pressure micro-hole of the air flotation disk through the distribution plate and the gas-liquid transfer plate, and is ejected to form a uniform support gas film between the bottom surface of the wafer and the air flotation disk, which suspends and lifts the entire wafer without rigid contact with the disk body. 3. Wafer positioning constraint: The vacuum adsorption holes synchronously output negative pressure to form a reverse constraint force in the local gas film, which limits the horizontal displacement of the wafer and ensures the wafer position accuracy; excess gas is discharged into the atmosphere through atmospheric connection holes and interconnecting trenches to stabilize the gas film thickness. 4. Wafer temperature control: The constant temperature gas film fully covers the bottom surface of the wafer, and the gas continuously convects and exchanges heat, realizing uniform temperature regulation throughout the wafer, and completing high-precision processes such as photolithography and inspection. 5. Unloading: Cut off the vacuum negative pressure, continuously introduce positive pressure gas to maintain suspension, and the robotic arm directly picks up the wafer.

[0038] Example 2: Multi-layer composite flow distribution pad type air flotation support platform like Figure 8 This embodiment is another independent whole machine replacement solution. The overall stacked structure is air flotation plate 8.1, distribution pad 8.2, air path transfer plate 8.3, distribution pad 8.4, distribution plate 8.5. The multi-layer air path pad is stacked to replace the single-layer gas-liquid transfer plate of embodiment 1. The gas-liquid heat exchange structure is integrated on the back of the air flotation plate.

[0039] Integrated liquid cooling structure on the back of the air-float plate: like Figure 9 The arrangement of air-floating island pads on the upper surface of the air-floating plate 8.1, the stiffness selection, and the 8 / 12-inch zoned air supply logic are completely consistent with those in Example 1. The difference is that the independent gas-liquid transfer plate is cancelled, and the back liquid channel 9.1 is directly processed on the lower surface of the air-floating plate opposite to the support surface. The constant temperature fluid is directly introduced into the back flow channel of the air-floating plate to directly heat / cool the entire air-floating plate. The heat exchange path is shorter and the temperature control response speed is faster.

[0040] Multi-layer composite distribution component structure: Distribution pads 8.2 and 8.4 are thin sealing gaskets with through-holes for positive pressure, vacuum, and atmospheric connection, serving as layered isolation and gas diversion; the intermediate gas transfer plate 8.3 integrates a through-hole gas channel to receive gas from the upper and lower distribution pads.

[0041] Bottom distribution plate 8.5 structure as follows Figure 10 The internally machined annular distribution grooves 10.1, 10.2, and 10.3 are equipped with independent positive pressure connecting holes 10.6, vacuum connecting holes 10.4, and exhaust connecting holes 10.5. External air sources, vacuum, and pressure relief pipelines are connected to the bottom of the distribution plate and distributed to each ring of air flotation islands of the air flotation plate through multi-stage stacked gaskets, realizing independent air supply control in different zones.

[0042] Features of this embodiment: 1. The liquid cooling channel is integrated into the back of the air flotation plate, eliminating the need for a separate gas-liquid transfer plate, resulting in a thinner overall machine that is suitable for workstations with limited installation space. 2. The multi-layer distribution gaskets provide layered sealing of the gas path, ensuring good gas path isolation and preventing interference between negative pressure, positive pressure, and pressure relief pathways. 3. The selection of air-floating island pad stiffness, multi-size wafer adaptation, and constant temperature air film heat exchange principle are exactly the same as in Example 1. Two complete machine solutions can be selected according to the structure of the on-site equipment.

[0043] Description of multiple alternative structures (extended implementation methods): 1. Air-floating island pad hybrid replacement: The same air-floating disk can be freely matched with high-rigidity and low-rigidity island pads. The preferred combination is high-rigidity in the center + low-rigidity at the edge. The arrangement density of the two types of island pads can be adjusted according to the wafer warpage. 2. Fluid medium replacement: The circulating liquid channel medium at constant temperature can be either pure water (for ambient / low temperature processes) or heat transfer oil (for high temperature processes), both of which fall within the scope of protection of this invention; 3. Liquid flow channel replacement: The liquid channel on the back of the gas-liquid transfer plate / air flotation plate can be individually processed using spiral, star-shaped, or zigzag patterns, or a combination of two or more flow channels; 4. Replacement of air-float support structure: The whole machine can be interchanged between the structure with island pad and the integrated microporous reinforcement structure without island pad to adapt to wafers with different deformations; 5. Replacement of the overall assembly structure: The overall assembly can be selected from the three-layer split gas-liquid transfer structure of Example 1 or the multi-layer distribution pad stacked structure of Example 2. The two structures are alternatives to each other.

[0044] Detailed explanation of the core temperature control mechanism of this invention: Existing air flotation equipment relies solely on simple gas purging for heat exchange, lacking a pre-temperature control structure. This results in a large temperature difference between the gas and the wafer / disk, leading to poor temperature uniformity. This invention uses a liquid-cooled disk to pre-temperature control the entire air flotation disk. Positive-pressure gas passes through the internal channels of the disk, achieving thorough heat exchange. The temperature of the ejected gas matches the target temperature of the wafer. A gas film covers the entire lower surface of the wafer, enabling continuous low-speed convection heat exchange without localized heat transfer blind spots. The temperature difference within the wafer surface can be controlled within a very small range. Simultaneously, the air film suspension eliminates localized temperature hotspots caused by rigid contact, balancing the dual requirements of load-bearing capacity and high-precision temperature control.

[0045] Wafer size compatibility implementation details: The air paths of the three rings of air-floating island cushions are independent of each other, and the external control valve can individually control the on / off state of the air path of each ring: 8-inch wafer operating condition: the third ring positive pressure and vacuum output are turned off, and only the first and second rings are supplied with gas. The support area matches the 8-inch wafer profile, and the annular groove 2.8 compensates for edge warping. 12-inch wafer operating condition: Three rings of air passages are opened simultaneously, and the support range extends outward to cover 12-inch wafers. The 2.10 ring groove is adapted to the edge deformation of larger diameter wafers. One set of equipment does not require replacing the air flotation disk; it can be compatible with two mainstream wafer specifications simply by switching the air path on and off, reducing equipment modification costs and downtime.

[0046] The beneficial effects of the technical solution of the present invention are: 1. This invention uses air film suspension bearing to replace the traditional rigid vacuum chuck, and the wafer is held without rigid contact, which greatly reduces the wafer holding stress, avoids deformation and damage to thin and warped wafers, and improves the wafer surface accuracy. 2. Integrated liquid-cooled constant temperature heat exchange structure, the entire air float is pre-cooled / preheated by constant temperature fluid, and the positive pressure gas forms a heat exchange gas film after being kept at a constant temperature by the disk. High-precision and uniform temperature control of the wafer is achieved by relying on the full-domain contact heat exchange of the gas. The temperature control consistency is far superior to solid contact heat conduction. 3. The air-floating island pad can be activated in a controlled manner in zones. One set of equipment is compatible with two mainstream wafer specifications, 8-inch and 12-inch, reducing equipment procurement and modification costs. 4. It provides three support structures: high-rigidity island pads, low-rigidity island pads, and island pad-free reinforced microvias. These can be flexibly selected according to the degree of wafer warpage, covering various wafer working conditions such as flat, slightly warped, and large deformation, and the equipment has strong versatility. 5. Two complete assembly solutions are provided: a three-layer split gas-liquid transfer structure and a multi-layer distribution pad stacked structure, which broadens the scope of patent protection and prevents design circumvention; the gas path and liquid path are independently distributed in layers, and the gas and liquid are completely isolated to avoid fluid contamination of the wafer process surface.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An air-floating support platform, characterized in that, This includes air flotation plates, gas-liquid transfer plates, and distribution plates; The air-float disk is provided with a positive pressure channel, a vacuum channel and an exhaust channel. Several air-float support units are arranged on the upper surface of the air-float disk. The air-float support units are equipped with positive pressure micro-holes, vacuum adsorption holes and atmospheric connection holes. The positive pressure micro-holes output positive pressure gas to form a supporting gas film between the wafer and the air-float disk to suspend and support the wafer. The vacuum adsorption holes output negative pressure to position and constrain the wafer. The atmospheric connection holes connect to the outside atmosphere to realize gas depressurization and exhaust. The gas-liquid transfer plate is fitted and disposed below the air flotation plate. A circulating liquid channel is opened in the gas-liquid transfer plate. A constant temperature liquid supply device is connected to the outside of the circulating liquid channel to introduce constant temperature fluid. The gas-liquid transfer plate conducts heat to the air flotation plate through surface contact, so that the gas flowing through the positive pressure micro-hole and the air flotation plate are kept at a constant temperature. The wafer is non-contact temperature control is performed by relying on the supporting gas film formed by the constant temperature gas. The distribution plate is fitted onto the side of the gas-liquid transfer plate away from the air flotation plate. The distribution plate has positive pressure distribution connection holes, vacuum distribution connection holes, and exhaust distribution connection holes, which respectively connect to the positive pressure passage interface, vacuum passage interface, and atmospheric passage interface in the air flotation plate, so as to realize the layered independent distribution and transportation of positive pressure gas, negative pressure vacuum, and depressurized gas.

2. The air-bearing support platform according to claim 1, characterized in that, The air-bearing support unit on the air-bearing disk is an air-bearing island pad. Multiple sets of air-bearing island pads are arranged concentrically in rings, at least in the first ring, second ring, and third ring. Only the first and second rings of air-bearing island pads are used to adapt to 8-inch wafers, while all three rings of air-bearing island pads are used simultaneously to adapt to 12-inch wafers. The air-bearing disk has annular grooves to adapt to the edge warping deformation of 8-inch wafers and annular grooves to adapt to the edge warping deformation of 12-inch wafers.

3. The air-bearing support platform according to claim 2, characterized in that, The air-floating island mat comprises two structural forms: The first type is a high-rigidity island pad, in which the island pad grooves and positive pressure micro-holes are arranged tangentially and at intervals, resulting in a slow exhaust rate; the second type is a low-rigidity island pad, in which the island pad grooves and positive pressure micro-holes are arranged concentrically, resulting in a fast exhaust rate; the air flotation disk can be arranged with a single structure air flotation island pad alone, or with a mixture of two structures of air flotation island pads.

4. The air-bearing support platform according to claim 1, characterized in that, The air-float also features an integrated reinforced support structure without island pads, eliminating independent air-float island pads. Multiple sets of positive pressure micro-holes are arranged concentrically, and vacuum ring grooves, exhaust ring grooves, and corresponding connecting channels are provided. The air-float support stiffness is improved by densely distributed positive pressure micro-holes, making it suitable for bearing large deformation wafers.

5. The air-bearing support platform according to claim 1, characterized in that, The air flotation disk has an internal annular groove. The positive pressure micro-holes of the same ring of air flotation support units are interconnected through the positive pressure annular groove. Each vacuum adsorption hole is interconnected through the vacuum annular groove. The exhaust connection holes are arranged at intervals or are set one-to-one with the air flotation island pad.

6. The air-bearing support platform according to claim 1, characterized in that, The circulating liquid channel of the gas-liquid transfer plate is a spiral, cross-shaped, or U-shaped flow channel. The side wall of the gas-liquid transfer plate is provided with a positive pressure passage interface, a vacuum passage interface, and an atmospheric connection interface, which are respectively connected to various distribution and connection holes of the distribution plate.

7. The air-bearing support platform according to claim 1, characterized in that, The side of the distribution plate facing the gas-liquid transfer plate is a sealing and fitting surface. The distribution plate is provided with an annular distribution groove, which is connected to the positive pressure connection hole, the vacuum connection hole, and the exhaust connection hole respectively.

8. An air-floating support platform, characterized in that, It includes an air flotation plate and a multi-layer flow distribution assembly, wherein the multi-layer flow distribution assembly is composed of a flow distribution pad, an air path adapter plate, and a flow distribution plate stacked in sequence; The upper surface of the air-float disk is arranged with several air-float island pads, and the lower surface of the air-float disk is opened with liquid circulation channels for introducing constant temperature fluid to achieve overall temperature uniformity; the distribution pad and the gas path transfer plate are opened with positive pressure connection channels, vacuum connection channels and atmospheric connection channels. The distribution disk is equipped with annular distribution groove and independent positive pressure connection channels, vacuum connection channels and exhaust connection channels. The multi-layer distribution component distributes positive pressure gas, vacuum negative pressure and depressurization gas in layers. The air-float disk suspends the wafer through air film and simultaneously completes the constant temperature regulation of the wafer.

9. The air-bearing support platform according to claim 8, characterized in that, The air-floating island pad of the air-floating disc is selected from one or a combination of two types: high-rigidity island pads and low-rigidity island pads.

10. The air-bearing support platform according to claim 1 or 8, characterized in that, The constant-temperature fluid is either circulating water or heat transfer oil; The wafer is supported without rigid contact by a gas film. The gas film formed by the constant temperature gas also serves as a heat transfer medium, and precise temperature control of the wafer is achieved through gas film heat exchange.

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