Wafer transfer fork arm

Abstract

A wafer transfer fork arm includes a fork arm body, a support column, and a piston cap. The fork arm body has a main air passage inside, and a chamber is formed on its bearing surface. The support column is disposed within the chamber and has a column air passage communicating with the main air passage. The piston cap is fitted around the outer periphery of the support column, and its sidewall has air holes. The piston cap is configured to move along the support column between an adsorption position and a cleaning position. This application utilizes the air holes on the sidewall of the piston cap, the column air passage of the support column, and the main air passage of the fork arm body to form a single air path. Based on this single air path, cleaning and adsorption operations are achieved by switching between negative and positive pressure, solving the problems of traditional dual-air path solutions.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and more specifically to a wafer transfer fork arm. Background Technology

[0002] In the semiconductor chip manufacturing industry, wafer transfer forks, as the execution components for wafer transfer, are a key carrier connecting various process steps.

[0003] In some related technologies, single-function fork arms are used, which only have vacuum adsorption and load-bearing capabilities and lack self-cleaning functions. Due to the lack of self-cleaning ability, particulate impurities are easily left on the working surface of the fork arm after multiple wafer transfers. These particles can directly scrape the wafer surface or cause environmental pollution, leading to a decrease in wafer yield. If this problem is solved by adding an external cleaning device, it will not only increase the overall size of the equipment, but also significantly prolong the transfer cycle and reduce production efficiency, making it unsuitable for the compact and efficient layout requirements of semiconductor production lines.

[0004] In other related technologies, forklifts with integrated cleaning functions often employ a dual-air-path independent layout, i.e., separate vacuum adsorption air path and purging cleaning air path. This approach has a redundant and complex air path structure, requiring separate design of flow channels, interfaces, and control components. Not only is the integration low and the assembly and maintenance costs high, but cross-contamination between the two air paths is also prone to occur, leading to insufficient adsorption vacuum or a decrease in cleaning airflow pressure when switching operating conditions. Summary of the Invention

[0005] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0006] To address the existing problems, this application provides a wafer transfer fork arm, comprising: The fork arm body has a main air passage inside, and the bearing surface of the fork arm body has an inwardly recessed chamber. A support column is disposed in the chamber, and the support column is provided with a column air passage communicating with the main air passage; A piston cap is fitted around the outer periphery of the support column, and the side wall of the piston cap is provided with an air hole that communicates with the air passage of the column. The piston cap is configured to move along the support column between an adsorption position and a cleaning position. When there is negative pressure airflow in the main air passage, the piston cap is in the adsorption position, and when in the adsorption position, the piston cap retracts into the cavity and its top is not higher than the bearing surface, so that the negative pressure airflow forms an adsorption gas field in the cavity through the air hole; When there is positive pressure airflow in the main air passage, the piston cap is in the clean position, and in the clean position, the piston cap extends out of the chamber and the air hole is located above the bearing surface, so that the positive pressure airflow forms a clean airflow on the bearing surface through the air hole.

[0007] In some embodiments of this application, the fork arm body includes a fork head and an arm body connected to the fork head along its length direction; The fork arm body includes, along its thickness direction, a stacked load-bearing layer, an air passage layer, and a support layer. The surface of the load-bearing layer away from the air passage layer is the load-bearing surface, and the main air passage is located within the air passage layer.

[0008] In some embodiments of this application, the airway layer is provided with a semi-open airway, and the bearing layer and / or the support layer seal the semi-open airway on the side facing the airway layer to form the main airway; one end of the main airway is connected to the column airway, and the support layer is provided with an air passage interface connected to the other end of the main airway.

[0009] In some embodiments of this application, one end of the main air passage extends to the fork head, and the other end extends to the rear end face of the arm body and forms an opening on the rear end face; the wafer transfer fork arm also includes a seal for sealing the opening; the air passage interface penetrates the support layer along the thickness direction and communicates with the main air passage.

[0010] In some embodiments of this application, the airway layer is provided with a flow guide groove at the fork head, one end of the main airway extends to the fork head and communicates with the flow guide groove, and the chamber is disposed on the bearing layer and communicates with the flow guide groove directly opposite to it in the thickness direction.

[0011] In some embodiments of this application, the flow guide groove includes a transverse groove and an oblique groove that are interconnected. The main air passage extends to one end of the fork head and communicates with the transverse groove. The chamber is disposed on the bearing layer and communicates with the oblique groove in the thickness direction. Both the transverse groove and the oblique groove have a stepped structure.

[0012] In some embodiments of this application, the piston cap is provided with a piston passage arranged along its axial direction, and the air hole is arranged radially within the side wall of the piston cap, and the air hole communicates with the column passage through the piston passage.

[0013] In some embodiments of this application, the piston cap includes a first section along its axial direction near the bearing surface and a second section located on the side of the first section away from the bearing surface, and the air hole is disposed in the first section; wherein, the radial dimension of the first section at each axial direction is smaller than the opening size of the chamber, and at least a portion of the radial dimension of the second section is larger than the opening size of the chamber.

[0014] In some embodiments of this application, at the adsorption position, there is a gap between the outer peripheral surface of the first section and the inner wall surface of the chamber, and the gap communicates with the pore.

[0015] In some embodiments of this application, the piston cap is frustum-shaped, and the piston cap has a small-diameter end face facing the bearing surface and a large-diameter end face away from the bearing surface.

[0016] The wafer transfer fork arm of this application integrates vacuum adsorption and self-cleaning functions by setting a piston cap sleeved on the outer periphery of the support column within the cavity of the fork arm body bearing surface, and utilizing a single air path formed by the air holes on the side wall of the piston cap, the column air channel of the support column, and the main air channel of the fork arm body. This single air path achieves cleaning and adsorption operations by switching between negative and positive pressure. On the one hand, it eliminates the risk of particle residue and wafer abrasion caused by the lack of cleaning ability of a single-function fork arm, while avoiding the increase in equipment size and the extension of transfer cycle time caused by external cleaning devices, significantly improving the production efficiency and yield of semiconductor production lines in a compact layout. On the other hand, it solves the problems of air path redundancy, structural complexity, and low integration in traditional dual-air path solutions, eliminates the potential cross-flow hazards between the two air paths, ensures the stability of the adsorption vacuum and the pressure intensity of the cleaning airflow, simplifies the assembly process, and significantly reduces subsequent operation and maintenance costs. Attached Figure Description

[0017] The following drawings, which are incorporated herein by reference and are used to understand this application, illustrate embodiments of the invention and their descriptions to explain the principles of the invention.

[0018] In the attached image: Figure 1 A schematic diagram of a wafer transfer fork arm in a specific embodiment of this application is shown.

[0019] Figure 2 This is a perspective view of the internal structure of a wafer transfer fork arm according to a specific embodiment of this application.

[0020] Figure 3 A schematic diagram of the internal structure of a wafer transfer fork arm according to a specific embodiment of this application is shown.

[0021] Figure 4 A schematic diagram of the piston cap according to a specific embodiment of this application is shown.

[0022] Figure 5 A schematic diagram of the piston cap according to a specific embodiment of this application is shown. Detailed Implementation

[0023] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0024] It should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. The same reference numerals denote the same elements throughout.

[0025] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0026] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0028] In some related technologies, single-function fork arms are used, which only have vacuum adsorption and load-bearing capabilities and lack self-cleaning functions. Due to the lack of self-cleaning ability, particulate impurities are easily left on the working surface of the fork arm after multiple wafer transfers. These particles can directly scrape the wafer surface or cause environmental pollution, leading to a decrease in wafer yield. If this problem is solved by adding an external cleaning device, it will not only increase the overall size of the equipment, but also significantly prolong the transfer cycle and reduce production efficiency, making it unsuitable for the compact and efficient layout requirements of semiconductor production lines.

[0029] In other related technologies, forklifts with integrated cleaning functions often employ a dual-air-path independent layout, i.e., separate vacuum adsorption air path and purging cleaning air path. This approach has a redundant and complex air path structure, requiring separate design of flow channels, interfaces, and control components. Not only is the integration low and the assembly and maintenance costs high, but cross-contamination between the two air paths is also prone to occur, leading to insufficient adsorption vacuum or a decrease in cleaning airflow pressure when switching operating conditions.

[0030] Furthermore, the cleaning air outlets of these fork arms are mostly fixed protruding structures, which disrupt the flatness of the bearing surface, causing uneven stress on the wafers during placement. This can easily lead to edge scraping, stress concentration, or even warping and cracking of large wafers. At the same time, existing cleaning fork arms typically rely on additional drive components such as motors and cylinders to control their movement. This not only increases structural complexity but also poses a risk of particles detaching from the drive components, violating the particle control requirements of ultra-clean processing environments.

[0031] To fully understand this application, detailed steps and structures will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0032] Below, for reference Figures 1-5 This application describes a wafer transfer fork arm 100 according to one embodiment. The wafer transfer fork arm 100 includes a fork arm body 110, a support column 120, and a piston cap 130. The fork arm body 110 has a main air passage 111 inside, and the bearing surface of the fork arm body 110 has an inwardly recessed chamber 112; the support column 120 is disposed in the chamber 112, and the support column 120 has a column air passage communicating with the main air passage 111; the piston cap 130 is sleeved on the outer periphery of the support column 120, and the side wall of the piston cap 130 has an air hole 131. The piston cap 130 is configured to move along the support column 120 between an adsorption position and a cleaning position. When there is negative pressure airflow in the main air passage 111, the piston cap 130 is in the adsorption position. In the adsorption position, the piston cap 130 retracts into the chamber 112 and its top is not higher than the bearing surface, so that the negative pressure airflow forms an adsorption air field in the chamber 112 through the air hole 131. When there is positive pressure airflow in the main air passage 111, the piston cap 130 is in the cleaning position. In the cleaning position, the piston cap 130 extends out of the chamber 112 and the air hole 131 is located above the bearing surface, so that the positive pressure airflow forms a cleaning airflow on the bearing surface through the air hole 131.

[0033] When the wafer transfer fork arm 100 performs the adsorption operation, the main air channel 111 inside the fork arm body 110 is first connected to an external negative pressure air source, creating a negative pressure state within the main air channel 111. At this time, the piston cap 130 installed in the chamber 112 is subjected to the pressure difference between the internal negative pressure and the external atmospheric pressure, moving along the support column 120 towards the chamber 112 until it retracts into the chamber 112, until the top of the piston cap 130 is no higher than the bearing surface, thus reaching the adsorption position. Under this physical state, the airflow in the chamber 112 is guided by the negative pressure, entering the column air channel within the support column 120 through the air holes 131 on the side wall of the piston cap 130, and then converging into the main air channel 111. This negative pressure airflow from the outside in forms an adsorption gas field in the chamber 112, using the pressure difference to fix the wafer to the bearing surface, ensuring the stability of the wafer during transport.

[0034] After the wafer is conveyed to the predetermined position and released, the conveyor fork 100 immediately enters the cleaning process. Positive pressure is created within the main air duct 111 by connecting it to an external positive pressure air source. The positive pressure airflow enters the column air duct inside the support column 120 along the main air duct 111. The resulting thrust drives the piston cap 130 to move away from the chamber 112 along the support column 120, switching the piston cap 130 from the adsorption position to the cleaning position. In the cleaning position, part of the piston cap 130 extends outside the chamber 112, so that the air holes 131 on its sidewall, which were originally inside the chamber 112, are now above the bearing surface. After the positive pressure airflow enters the piston cap 130 through the column air duct, it is ejected outward through the air holes 131, forming a directional cleaning airflow on the bearing surface, effectively removing particulate impurities remaining on the surface of the fork 100.

[0035] For example, during cleaning operations, positive pressure airflow drives the piston cap 130 to rise, making its top 0.8mm-1.2mm higher than the bearing surface; during adsorption operations, negative pressure airflow drives the piston cap 130 to retract into the chamber 112, keeping its top flush with the bearing surface.

[0036] Therefore, this application integrates vacuum adsorption and self-cleaning functions by setting a piston cap 130 sleeved on the outer periphery of the support column 120 within the chamber 112 of the bearing surface of the fork arm body 110, and utilizing a single air path composed of the air holes 131 on the side wall of the piston cap 130, the column air passage of the support column 120, and the main air passage 111 of the fork arm body 110. This single air path achieves cleaning and adsorption operations by switching between negative and positive pressure. On the one hand, it eliminates the risk of particle residue and wafer scratching caused by the lack of cleaning ability of the single-function fork arm 100, and avoids the increase in equipment size and the extension of transfer cycle caused by external cleaning devices, significantly improving the production efficiency and yield of semiconductor production lines in a compact layout. On the other hand, it solves the problems of air path redundancy, structural complexity and low integration in the traditional dual air path scheme, eliminates the potential cross-flow hazards between the two air paths, ensures the stability of the adsorption vacuum and the pressure intensity of the cleaning airflow, simplifies the assembly process, and significantly reduces subsequent operation and maintenance costs.

[0037] Relying on the adaptive lifting action of the piston cap 130 within the chamber 112, the piston cap 130 can be completely retracted to a position where its top does not exceed the bearing surface during adsorption operations. This ensures an extremely flat wafer contact surface, overcomes the uneven force and local stress concentration caused by traditional fixed protruding structures, eliminates the risk of edge scraping, warping, or cracking that may occur during wafer transfer, and significantly improves the stability and reliability of wafer bearing.

[0038] In addition, the piston cap 130 is driven by the positive and negative pressure difference in the main air passage 111 to achieve the lifting action. There is no need to configure additional drive components such as motors and cylinders. This not only greatly simplifies the mechanical structure, but also avoids the risk of particle shedding and contamination generated by traditional drive components from the source. It perfectly meets the stringent particle control requirements of 3nm and below advanced processes for ultra-clean processing environment.

[0039] In some embodiments, the piston cap 130 is sleeved on the outer periphery of the support column 120, and the two are in a sliding fit. When positive or negative pressure airflow is introduced into the main air passage 111, the piston cap 130 can be driven to slide up and down along the axial direction of the support column 120 to achieve lifting and lowering action. There are various specific sliding fit forms, which are not limited in this application. For example, the piston cap 130 and the support column 120 adopt a clearance sliding fit; or a slide rail-slider fit (one of the piston cap 130 and the support column 120 is provided with a slide rail, and the other is provided with a corresponding slider, and relative sliding is achieved through the cooperation of the slide rail and the slider); or a guide groove-guide block fit (one of the piston cap 130 and the support column 120 is provided with a guide groove, and the other is provided with a corresponding guide block, and relative sliding is achieved through the cooperation of the guide groove and the guide block).

[0040] In some embodiments, such as Figure 1As shown, the fork arm body 110 includes a fork head and an arm body connected to the fork head along its length direction; the fork arm body 110 includes a stacked bearing layer, an air passage layer and a support layer along its thickness direction, the surface of the bearing layer away from the air passage layer is the bearing surface, and the main air passage 111 is located in the air passage layer.

[0041] Specifically, the fork head, as the working end that performs the function of carrying and transferring wafers, is typically adapted in shape and size to the wafers to be transferred. For example, the fork head can adopt a U-shaped structure, and its size can be adjusted according to different wafer sizes such as 8 inches, 10 inches, or 12 inches; this application does not limit this. The arm body is connected to the rear end of the fork head and mainly serves to provide structural support and power connection with the external robotic arm drive mechanism. To balance structural rigidity and lightweight requirements, the arm body can adopt a gradient structure design and has a through hole 116 at its end for connecting with the external robotic arm drive mechanism.

[0042] In terms of thickness, the fork arm body 110 exhibits a layered structure. The support layer is located at the top layer, and its surface away from the air duct layer (i.e., the top surface) forms a support surface for placing the wafer, ensuring stable wafer transport by maintaining a highly flat contact interface. The air duct layer is located in the middle, and the main air duct 111 is entirely disposed within the air duct layer. The support layer is located at the bottom, providing the necessary mechanical strength support for the entire fork arm 100.

[0043] In one example, the flatness of the bearing surface is controlled within 0.02mm, thereby ensuring that the wafer can obtain a uniform force distribution during the adsorption operation, eliminating the risk of large-size wafer scratches and warping caused by local protrusions in traditional fixed air channels, and ensuring the safety of the wafer during the bearing process.

[0044] In some embodiments, a semi-open airway is provided in the airway layer, and the bearing layer and / or support layer seal the semi-open airway on the side facing the airway layer to form a main airway 111; one end of the main airway 111 is connected to the column airway, and the support layer is provided with an airway interface 115 connected to the other end of the main airway 111.

[0045] Specifically, a semi-open airway can refer to an airway that is open on the side facing the support layer or the bearing layer, and is sealed off by the side of the support layer or the bearing layer facing the airway layer to form the main airway 111; or it can refer to an airway that is open on the side facing the support layer, and is sealed off by the side of the support layer facing the airway layer, and the airway that is open on the side facing the support layer, and is sealed off by the side of the support layer facing the airway layer to form the main airway 111.

[0046] By setting a semi-open airway within the airway layer and sealing it with the support layer and / or the bearing layer facing the airway layer, a complete main airway 111 is formed inside the fork arm 100. The air passage interface 115 located on the support layer connects to the end of the main airway 111 for connecting to external positive and negative pressure air sources. This layered structural design based on the support layer, airway layer, and bearing layer effectively reduces the processing difficulty of long-distance airways inside the fork arm 100, and combined with the sealing and fixing between the layers, ensures the sealing reliability and pressure stability during airflow transmission.

[0047] Regarding the connection and sealing, the load-bearing layer, airway layer, and support layer can be connected by adhesive bonding or by bolts for sealing and fixing. This application does not limit the specific connection method. In addition, sealing gaskets made of fluororubber or other suitable materials can be added between the load-bearing layer and the airway layer, and between the airway layer and the support layer, to effectively prevent gas leakage inside the main airway and to prevent external environmental particles from penetrating into the main airway 111.

[0048] In some embodiments, such as Figure 2 and Figure 3 As shown, one end of the main air passage 111 extends to the fork head, and the other end extends to the rear end face of the arm body, where an opening 1111 is formed; the wafer transfer fork arm 100 also includes a seal 140 that seals the opening 1111; the air passage interface 115 penetrates the support layer along the thickness direction and communicates with the main air passage 111.

[0049] Specifically, the rear end face refers to the narrow side surface at the end of the arm along its length, and the rear end face is perpendicular to the length direction of the arm. The main air passage 111 is formed by extending inward from the rear end face during the manufacturing process, and is sealed by installing a seal 140 (such as a sealing bolt or sealing plug) at the opening 1111 on the rear end face. This structure ensures absolute sealing of the main air passage 111 in the non-working direction, thereby effectively preventing leakage of internal pressurized airflow to the outside.

[0050] In some embodiments, the airway layer is provided with a flow guide groove at the fork head, one end of the main airway 111 extends to the fork head and communicates with the flow guide groove, and the chamber 112 is disposed on the bearing layer and communicates with the flow guide groove in the thickness direction.

[0051] Specifically, the column air passage located inside the support column 120 within chamber 112 is connected to the guide groove. During adsorption operations, negative pressure airflow enters the guide groove through the column air passage and then merges into the main air passage 111; during cleaning operations, positive pressure airflow enters the guide groove through the main air passage 111 and then flows into the column air passage. The guide groove acts as a pressure stabilizing buffer between the main air passage 111 and the column air passage, effectively balancing the pressure distribution of the airflow. This provides a more stable and consistent airflow drive field for the piston cap 130, ensuring the stability of the wafer during adsorption and cleaning operations.

[0052] In some embodiments, such as Figure 2 and Figure 3 As shown, the flow guide groove includes a transverse groove 113 and an oblique groove 114 that are interconnected. The main air passage 111 extends to one end of the fork head and communicates with the transverse groove 113. The chamber 112 is disposed on the bearing layer and communicates with the oblique groove 114 in the thickness direction. The transverse groove 113 and the oblique groove 114 both have a stepped structure.

[0053] Specifically, the guide grooves adopt a multi-segment structure, with interconnected transverse grooves 113 and oblique grooves 114 forming the guiding path between the main air duct 111 and the column air duct. Taking adsorption as an example, after the airflow exits from the column air duct, it enters the transverse groove 113 via the oblique groove 114 and finally merges into the main air duct 111. Taking cleaning as an example, after leaving the main air duct 111, the airflow first enters the transverse groove 113 for initial diffusion, and then, guided by the oblique groove 114, is injected directly into the column air duct along the thickness direction. This segmented design achieves a smooth transition of airflow under different operating conditions and provides structural support for the uniform distribution of the pressure field.

[0054] Within the transverse groove 113, the stepped structure, combined with the laterally extending groove, effectively disperses the airflow and balances the pressure distribution, ensuring highly uniform diffusion of positive and negative pressure along the width of the fork arm 100. This fundamentally avoids wafer adsorption shift or cleaning blind spots caused by drastic local air pressure fluctuations. Simultaneously, the stepped structure within the oblique groove 114 allows for step-by-step adjustment of the airflow velocity. Utilizing the guiding and buffering effect of the stepped surface, it directs the airflow in an orderly manner. This avoids turbulence caused by sudden airflow changes and reduces the risk of direct airflow impact on the wafer, while significantly improving the air pressure consistency in the contact area between the fork arm 100 and the wafer. Ultimately, this achieves a high degree of synergy between cleaning efficiency and material protection.

[0055] For example, such as Figure 2 and Figure 3 As shown, each of the two forks of the U-shaped fork head is provided with an oblique groove 114, and the base of the U-shaped fork head is provided with a transverse groove 113, and the two ends of the transverse groove 113 are respectively connected to the two oblique grooves 114.

[0056] In some embodiments, the fork arm body 110 may be provided with one or more chambers 112, which is not limited in this application. Taking the fork arm body 110 having multiple chambers 112 as an example, in a specific embodiment, such as Figure 2 and Figure 3 As shown, each end of the two inclined grooves 114 is provided with a chamber 112, for a total of four chambers 112. Each chamber 112 is provided with a support column 120, and the column air passage inside the support column 120 is connected to the inclined groove 114 in which it is located. Each support column 120 is fitted with a piston cap 130 on its outer circumferential surface.

[0057] In some embodiments, the piston cap 130 has a piston passage arranged along its axial direction inside, and an air hole 131 is arranged radially inside the side wall, and the air hole 131 communicates with the column passage through the piston passage.

[0058] Specifically, the piston air passage and the air hole 131 form an interconnected L-shaped airflow path inside the piston cap 130, allowing positive or negative pressure airflow to switch directions between axial and radial directions via this path. For example, during adsorption operations, due to the negative pressure formed in the main air passage 111, the airflow is guided by the pressure difference, first entering the air hole 131 from the gap between the piston cap 130 and the chamber 112 and flowing radially. Then, at the path bend, it enters the axially arranged piston air passage, flows through the column air passage, and finally merges into the main air passage 111. During cleaning operations, the positive pressure airflow is first delivered from the main air passage 111 to the column air passage, then enters the piston air passage through the column air passage. Afterward, the airflow enters the air hole 131 at the path bend and flows radially, then is directionally discharged towards the bearing surface through the air hole 131 to achieve purging.

[0059] In some embodiments, each piston cap 130 may have one or more air holes 131 on its sidewall, which is not limited in this application. When multiple air holes 131 are provided, the multiple air holes 131 may be evenly or non-uniformly distributed along the circumference of the piston cap 130; at the same time, the aperture of the air holes 131 can be set according to actual needs, which is also not limited in this application.

[0060] In one specific embodiment, each piston cap 130 has six air holes 131 evenly arranged on its sidewall, and the diameter of the air holes 131 is 0.5 mm.

[0061] In some embodiments, the piston cap 130 includes a first section near the bearing surface and a second section on the side of the first section away from the bearing surface along its axial direction, and an air hole 131 is provided in the first section; wherein the radial dimension of the first section at each axial direction is smaller than the opening size of the chamber 112, and at least a portion of the radial dimension of the second section is larger than the opening size of the chamber 112.

[0062] Specifically, the radial dimension of the first section at all points along the axial direction is smaller than the opening size of the chamber 112. This ensures that during cleaning operations, the first section can smoothly pass through the opening of the chamber 112 and extend outward, thereby switching the piston cap 130 to the cleaning position. In the cleaning position, the air hole 131, which was originally located in the chamber 112, rises above the bearing surface, thereby guiding the positive pressure airflow towards the bearing surface to perform purging cleaning.

[0063] Meanwhile, since at least part of the radial dimension of the second section is larger than the opening size of the chamber 112, the opening edge of the chamber 112 can physically limit the piston cap 130 in the cleaning position, thereby effectively preventing it from leaving the chamber 112 under positive pressure airflow, ensuring the operational stability and safety during cleaning operations.

[0064] It should be noted that the first and second sections are merely artificial divisions of the piston cap 130; the piston cap 130 is essentially a one-piece, integral structural component. For example... Figure 5 As shown, region A along the axial direction (i.e., the x-direction in the figure) corresponds to the first segment, and the cross-sectional dimension of region A at all points along the axial direction is smaller than the opening size of chamber 112; region B corresponds to the second segment, and the cross-sectional dimension of region B at least at one point along the axial direction is larger than the opening size of chamber 112. With this configuration, when positive pressure airflow is introduced into the main air passage 111, region A can extend outward from the opening of chamber 112, while region B can prevent the piston cap 130 from detaching from chamber 112.

[0065] In some embodiments, at the adsorption position, there is a gap between the outer peripheral surface of the first section and the inner wall surface of the chamber 112, and the gap communicates with the vent 131.

[0066] Specifically, by creating a gap between the outer peripheral surface of the first section and the inner wall of the chamber 112, and keeping this gap connected to the vent 131, it can be ensured that when in the adsorption position, the external airflow guided by negative pressure can smoothly flow from the bearing surface through the gap into the vent 131, thereby creating an adsorption flow field in a local area of ​​the bearing surface, achieving stable adsorption and reliable bearing of the wafer.

[0067] For example, the size of the gap can be 0.01mm-0.02mm, or any other suitable value, without limitation.

[0068] As a specific example, such as Figure 4 As shown, the piston cap 130 adopts a frustum-shaped structure, which has a small-diameter end face facing the bearing surface and a large-diameter end face away from the bearing surface.

[0069] Specifically, by configuring the piston cap 130 into a frustum-shaped configuration with its small-diameter end facing the bearing surface, the piston cap 130 forms a gradually expanding geometric profile in the axial direction—a conical geometric profile. This conical geometric profile ensures that, in the adsorption position, its small-diameter end sidewall can leave sufficient gap with the inner wall of the chamber 112 to guide the negative pressure airflow. When switching to the cleaning position, the large-diameter end face can utilize its radial size advantage to form a reliable physical limit with the opening edge of the chamber 112. Thus, while simplifying the structure, the shape characteristics of a single component cleverly achieve the dual technical effects of negative pressure conduction and upward limit.

[0070] For example, the side wall of the frustum-shaped piston cap 130 is inclined at 20° to 40° relative to the central axis of the piston cap 130, specifically 30°, or it can be any other suitable angle, which is not limited.

[0071] Of course, this application does not limit the piston cap 130 to adopt a frustum-shaped structure. In practical applications, it can be replaced with a frustum-shaped, stepped columnar, or other suitable geometric configurations with radial dimension gradients, depending on the shape of the chamber 112. As long as the shape configuration can ensure that a gap is reserved between the piston cap 130 and the inner wall of the chamber 112 for airflow in the adsorption position, and the physical limit of the upward stroke is achieved through local dimension interference in the cleaning position, thereby meeting the functional requirements of negative pressure conduction and anti-detachment protection, it should fall within the protection scope claimed by this application.

[0072] In some embodiments, such as Figure 4 As shown, the top edge of the piston cap 130 is provided with a rounded corner 132 to eliminate sharp edges and avoid scratching the wafer edge, thus preventing wafer damage caused by sharp structures. Specifically, the size of the rounded corner 132 can be R0.2mm, or it can be any other suitable value, which is not limited in this application.

[0073] In some embodiments, the fork arm body 110 may be made of hard anodized aluminum alloy, while the piston cap 130 may be made of ceramic. This combination of materials, possessing high wear resistance and ultra-clean properties, effectively adapts to the demanding production environments of advanced processes, ensuring excellent stability of the components during long-term operation. Of course, in specific application scenarios, the fork arm body 110 and piston cap 130 may also be made of any other suitable materials; this application does not impose any limitations on this.

[0074] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0075] Similarly, it should be understood that, in order to simplify this application and aid in understanding one or more aspects of the application, various features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, the point of application is that the corresponding technical problem can be solved with fewer features than all of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0076] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0077] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A wafer transfer fork arm, comprising: include: The fork arm body has a main air passage inside, and the bearing surface of the fork arm body has an inwardly recessed chamber. A support column is disposed in the chamber, and the support column is provided with a column air passage communicating with the main air passage; A piston cap is fitted around the outer periphery of the support column, and the side wall of the piston cap is provided with an air hole that communicates with the air passage of the column. The piston cap is configured to move along the support column between an adsorption position and a cleaning position. When there is negative pressure airflow in the main air passage, the piston cap is in the adsorption position, and when in the adsorption position, the piston cap retracts into the cavity and its top is not higher than the bearing surface, so that the negative pressure airflow forms an adsorption gas field in the cavity through the air hole; When there is positive pressure airflow in the main air passage, the piston cap is in the clean position, and in the clean position, the piston cap extends out of the chamber and the air hole is located above the bearing surface, so that the positive pressure airflow forms a clean airflow on the bearing surface through the air hole.

2. The wafer transfer fork arm of claim 1, wherein, The fork arm body includes a fork head and an arm body connected to the fork head along its length direction; The fork arm body includes, along its thickness direction, a stacked load-bearing layer, an air passage layer, and a support layer. The surface of the load-bearing layer away from the air passage layer is the load-bearing surface, and the main air passage is located within the air passage layer.

3. The wafer transfer fork arm of claim 2, wherein, The airway layer has a semi-open airway, and the bearing layer and / or the support layer seal the semi-open airway on the side facing the airway layer to form the main airway; one end of the main airway is connected to the column airway, and the support layer has an air passage interface connected to the other end of the main airway.

4. The wafer transfer fork arm of claim 3, wherein, One end of the main air passage extends to the fork head, and the other end extends to the rear end face of the arm body, where an opening is formed; the wafer transfer fork arm also includes a seal that seals the opening; the air passage interface penetrates the support layer along the thickness direction and communicates with the main air passage.

5. The wafer transfer fork arm of claim 2, wherein, The airway layer has a flow guide groove at the fork head, one end of the main airway extends to the fork head and communicates with the flow guide groove, and the chamber is disposed on the bearing layer and communicates with the flow guide groove in the thickness direction.

6. The wafer transfer fork arm of claim 5, wherein, The flow guide groove includes a transverse groove and an oblique groove that are interconnected. The main air passage extends to one end of the fork head and communicates with the transverse groove. The chamber is disposed on the bearing layer and communicates with the oblique groove in the thickness direction. Both the transverse groove and the oblique groove have a stepped structure.

7. The wafer transfer fork arm of claim 1, wherein, The piston cap has a piston passage arranged along its axial direction inside, and the air hole is arranged radially inside the side wall of the piston cap, and the air hole communicates with the column passage through the piston passage.

8. The wafer transfer fork arm as described in claim 1, characterized in that, The piston cap includes, along its axial direction, a first section near the bearing surface and a second section located on the side of the first section away from the bearing surface, with the air hole disposed in the first section; wherein, the radial dimension of the first section at each axial point is smaller than the opening size of the chamber, and at least a portion of the radial dimension of the second section is larger than the opening size of the chamber.

9. The wafer transfer fork arm as described in claim 8, characterized in that, At the adsorption position, there is a gap between the outer peripheral surface of the first section and the inner wall surface of the chamber, and the gap communicates with the pore.

10. The wafer transfer fork arm as described in claim 1, characterized in that, The piston cap is frustum-shaped and has a small-diameter end face facing the bearing surface and a large-diameter end face away from the bearing surface.

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