Stable clamping wafer chuck

Abstract

The application discloses a stable clamping wafer chuck and belongs to the technical field of semiconductor processing. The wafer chuck comprises a chuck base, the chuck base comprises an upper layer, a metal middle layer and a lower layer, and the chuck base is provided with at least four mounting holes; a chuck pin is movably arranged in the mounting hole, the chuck pin comprises a fixed part and a replacement part which are connected in an upper-lower mode, the replacement part comprises a wafer support and a clamping piece, the wafer support and the clamping piece are integrally formed and can rotate around the axis of the wafer support, the upper surface of the wafer support is used for supporting a wafer, the clamping piece is used for clamping the wafer after rotating around the axis of the wafer support, and a pressing piece is further arranged on the clamping piece; a limiting piece is sleeved on the outer periphery of the chuck pin and is used for limiting the up-down position of the replacement part when the replacement part rotates; and a driving mechanism is used for driving the chuck base and the chuck pin to rotate. Through the overall design of the wafer chuck, the stability of wafer clamping is improved, the driving and transmission structures required for realizing the function are simplified, and the production efficiency is improved.

Description

Technical Field

[0001] This application relates to a stable wafer chuck, belonging to the field of semiconductor processing technology. Background Technology

[0002] In integrated circuit manufacturing, multiple wet processing steps are involved. Wet processing involves immersing or rinsing the wafer with liquid chemicals such as acids, alkalis, and organic compounds to clean surface particles, remove reactive polymers, and etch surface films. As the requirements for process efficiency have increased, wet processing equipment has gradually shifted from early batch processing to single-wafer processing.

[0003] The clamping device acts on the wafer surface, requiring it to ensure uniform force distribution and stable fixation to the chuck during high-speed rotation. This prevents loosening, wafer wear, and reduced processing accuracy. Because wafers are generally thin and processing often involves acids, alkalis, and organic solvents, the chuck pins used to clamp the wafer wear quickly. Wear reduces the clamping capacity of the pins, and when the chuck rotates the wafer at high speed, the wafer may rotate eccentrically due to inaccurate positioning. In this case, the wafer will fluctuate vertically. If clamping is achieved solely through force applied to the wafer's sides, there is a high risk of wafer detachment, potentially causing production accidents.

[0004] In existing technologies, wafer clamping on the sides and top and bottom surfaces is often achieved through rotational and lifting drives, which complicates the drive and transmission structure. Therefore, it is necessary to design a wafer chuck that can clamp in two directions with a single drive. Utility Model Content

[0005] To address the aforementioned issues, this application proposes a stable wafer chuck that enables direct and rapid radial and axial clamping of wafers via a single drive. This simplifies the design of the wafer chuck's drive and transmission components, maintaining stable wafer clamping while reducing the wafer chuck's production costs.

[0006] According to one aspect of this application, a stable wafer chuck is provided, comprising: A chuck base, comprising an upper layer, a middle metal layer, and a lower layer, wherein a circular hole is provided in the center of the chuck base, and at least four mounting holes are provided circumferentially; A chuck pin is movably disposed within the mounting hole. The chuck pin includes a fixed part and a replacement part that engage with each other. The replacement part includes a wafer tray and a clamping member. The upper end surface of the clamping member is higher than the upper end surface of the wafer tray. The wafer tray and the clamping member are integrally formed and can rotate around the axis of the wafer tray. The upper surface of the wafer tray is used to support the wafer. After rotating around the axis of the wafer tray, the clamping member is used to clamp the wafer. The clamping member is also provided with a pressing member. A limiting member is sleeved on the outer periphery of the chuck pin and connected to the chuck seat. The limiting member is used to limit the up and down position of the replacement part when it rotates. A drive mechanism for driving the chuck holder to rotate about its axis and for driving the chuck pin to rotate about the axis of the wafer holder.

[0007] Specifically, the upper layer is an isolation layer made of corrosion-resistant material, the middle metal layer is provided with a transmission mechanism that can be mechanically connected to the drive mechanism and driven by electricity to achieve the rotation of the chuck pin, and the lower layer is provided with mounting holes for connection with the drive mechanism to achieve motion control of the chuck seat.

[0008] Specifically, the limiting member and the chuck seat can be detachably connected by snap-fit, or they can be fixedly connected by adhesive or integral molding.

[0009] Optionally, the inner circumference of the limiting member is provided with a first thread, and the outer circumference of the clamping member is provided with a second thread, wherein the first thread and the second thread cooperate.

[0010] Specifically, the rotation direction of the first thread is such that it enables the clamping component to rotate and clamp, and the clamping component to screw in.

[0011] Optionally, the inner circumference of the limiting member is provided with a sliding groove distributed in a spiral shape along its inner circumference, and the outer surface of the wafer holder is provided with a key, the key engaging with the sliding groove.

[0012] Optionally, the upper end of the fixing part is provided with a protrusion, and the lower end of the replacement part is provided with a first groove, the first groove matching the shape of the protrusion of the fixing part.

[0013] Specifically, the lower surface of the first groove does not fit against the lower surface of the protrusion.

[0014] Optionally, the lower end of the replacement part is fixedly connected to a spring, the inner diameter of which is larger than the outer diameter of the protrusion of the fixing part.

[0015] Optionally, the protrusion is provided with ribs, and a second groove is provided on the inner surface of the first groove, the second groove matching the shape of the ribs.

[0016] Optionally, the pressing member is composed of a plurality of pressing strips.

[0017] Optionally, the maximum distance between the center of the wafer holder and the chuck base is greater than the radius of the wafer.

[0018] Optionally, the upper surface of the chuck seat is a conical surface.

[0019] Optionally, the angle between the generatrix of the conical surface and the horizontal plane is 2~5°.

[0020] The beneficial effects that this application may produce include, but are not limited to: 1. The wafer chuck provided in this application restricts the vertical position of the replacement part during rotation by setting a limiting member, thereby converting the rotational motion of the replacement part into rotational motion and vertical movement. This allows the wafer chuck to clamp the wafer in both radial and vertical directions, improving the stability of wafer clamping. The above process can be achieved simply by driving the rotation of the replacement part, simplifying the wafer chuck control structure, saving space in the lower drive mechanism of the wafer chuck, and improving production efficiency.

[0021] 2. The wafer chuck provided in this application, by setting the chuck pin as a fixed part and a replacement part, can quickly replace the replacement part when the replacement part is worn to a certain extent without disassembling and replacing the entire chuck pin. This not only improves work efficiency, but also avoids corrosion of the metal middle layer of the chuck seat caused by the disassembly and assembly of the chuck pin, and also saves the material cost of the replacement parts. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a front view schematic diagram of the wafer chuck involved in the embodiments of this application; Figure 2 For this application Figure 1 A magnified view of a section at point A in the middle; Figure 3 This is a top view of the chuck pin involved in an embodiment of this application; Figure 4 This is a top view of the fixing part involved in the embodiment of this application; List of components and reference numerals: 1. Chuck holder; 2. Chuck pin; 3. Fixing part; 4. Replacement part; 5. Wafer holder; 6. Clamping part; 7. Protrusion; 8. Limiting part; 9. Pressing part; 10. First thread; 11. Second thread; 12. Spring; 13. Rib. Detailed Implementation

[0023] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0024] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0026] Furthermore, it should be understood in the description of this application that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application 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. Therefore, they should not be construed as limitations on this application.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0030] The wafer chuck in this application is only used to hold the wafer during wafer cleaning, etching and other processes. Since the wafer needs to be rotated during the above-mentioned cleaning, etching and other processes, the wafer chuck in this application can be connected to an additional drive mechanism, which drives the device to rotate in order to process the wafer.

[0031] refer to Figure 1-4 Embodiments of this application provide a stable wafer chuck, comprising: The chuck base 1 includes an upper layer, a metal middle layer and a lower layer. The chuck base 1 has a circular hole in the middle and at least four mounting holes in the circumferential direction. A chuck pin 2 is movably disposed within the mounting hole. The chuck pin 2 includes a fixing part 3 and a replacement part 4 that engage with each other. The replacement part 4 includes a wafer tray 5 and a clamping member 6. The upper end surface of the clamping member 6 is higher than the upper end surface of the wafer tray 5. The wafer tray 5 and the clamping member 6 are integrally formed and can rotate around the axis of the wafer tray 5. The upper surface of the wafer tray 5 is used to support the wafer. After rotating around the axis of the wafer tray 5, the clamping member 6 is used to clamp the wafer. The clamping member 6 is also provided with a pressing member 9. The limiting member 8 is sleeved on the outer periphery of the chuck pin 2 and connected to the chuck seat 1. The limiting member 8 is used to limit the up and down position of the replacement part 4 when it rotates. A driving mechanism is provided for driving the chuck holder 1 to rotate about its axis and for driving the chuck pin 2 to rotate about the axis of the wafer holder 5.

[0032] In this solution, by setting a limiting member 8 to restrict the vertical position of the replacement part 4 during rotation, the rotational motion of the replacement part 4 is converted into rotational motion and vertical movement, so that the wafer chuck clamps the wafer in both radial and vertical directions, improving the stability of wafer clamping. The above process can be achieved simply by driving the rotation of the replacement part 4, which simplifies the wafer chuck control structure, saves space in the lower drive mechanism of the wafer chuck, and improves production efficiency.

[0033] In one embodiment, the inner circumference of the limiting member 8 is provided with a first thread 10, and the outer circumference of the clamping member 6 is provided with a second thread 11, wherein the first thread 10 and the second thread 11 cooperate.

[0034] In this design, the vertical movement of the clamping component 6 is achieved through a threaded connection.

[0035] In one embodiment, the inner circumference of the limiting member 8 is provided with a sliding groove distributed in a spiral shape along its inner circumference, and the outer surface of the wafer holder 5 is provided with a key, which cooperates with the sliding groove.

[0036] In this solution, the clamping component 6 is moved vertically by sliding a pin on a spirally distributed groove.

[0037] In one embodiment, the upper end of the fixing part 3 is provided with a protrusion 7, and the lower end of the replacement part 4 is provided with a first groove, the shape of which matches the protrusion 7 of the fixing part 3.

[0038] Specifically, the lower surface of the first groove does not fit with the lower bottom surface of the protrusion 7, providing a certain space for the up-and-down movement of the replacement part 4.

[0039] In one embodiment, the lower end of the replacement part 4 is fixedly connected to a spring 12, and the inner diameter of the spring 12 is larger than the outer diameter of the protrusion 7 of the fixing part 3.

[0040] The spring 12 can provide a certain support for the replacement part 4. At the same time, when the wafer is clamped and subjected to lateral force, it can provide a small amount of elastic displacement rather than rigid friction, thereby reducing the wear of the wafer clamping part 6.

[0041] In one embodiment, the protrusion 7 is provided with a rib 13, and a second groove is provided on the inner surface of the first groove, the second groove matching the shape of the rib 13.

[0042] The structure of the rib 13 and the groove makes the transmission between the fixed part 3 and the replacement part 4 more efficient, which can reduce operating costs.

[0043] In one embodiment, the pressing member 9 is composed of a plurality of pressing strips.

[0044] Compared to a single pressure plate, the design of the pressure strip reduces the contact area with the wafer, thereby reducing the potential water accumulation problem; at the same time, it avoids excessive pressure on the wafer due to the small contact area, thus preventing the risk of wafer breakage.

[0045] In one embodiment, the maximum distance between the center of the wafer holder 5 and the center of the chuck 1 is greater than the radius of the wafer.

[0046] In one embodiment, the upper surface of the chuck holder 1 is a conical surface, which facilitates the discharge of cleaning liquid during the wafer cleaning process and prevents liquid accumulation in the chuck holder 1 from contaminating the wafer.

[0047] In one embodiment, the angle between the generatrix of the conical surface and the horizontal plane is 2~5°.

[0048] The angle between the generatrix of the cone and the horizontal plane is 2~5°. This angle not only allows the cleaning liquid to drain quickly, but also prevents the stability of the chuck pin 2 from deteriorating or affecting the wafer due to the excessive height difference between the center and the outer periphery of the chuck seat 1.

[0049] The wafer chuck operates as follows: the wafer is placed on the wafer holder 5 on the chuck pin 2, the drive mechanism drives the chuck pin 2 to rotate around the axis of the wafer holder 5 so that the clamping member 6 holds the wafer in the radial direction, and the drive mechanism drives the chuck base 1 to rotate around its axis, thereby rotating the wafer and performing the rinsing operation.

[0050] During this process, the limiting component 8 moves downward under the action of the thread or the slide, which drives the pressing component 9 at its upper end to clamp the wafer from the top, improving the stability of wafer clamping, reducing the probability of unexpected shutdown during wafer rotation, and improving production efficiency.

[0051] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0052] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A stable wafer chuck, characterized in that, include: A chuck base, comprising an upper layer, a middle metal layer, and a lower layer, wherein a circular hole is provided in the center of the chuck base, and at least four mounting holes are provided circumferentially; A chuck pin is movably disposed within the mounting hole. The chuck pin includes a fixed part and a replacement part that engage with each other. The replacement part includes a wafer tray and a clamping member. The upper end surface of the clamping member is higher than the upper end surface of the wafer tray. The wafer tray and the clamping member are integrally formed and can rotate around the axis of the wafer tray. The upper surface of the wafer tray is used to support the wafer. After rotating around the axis of the wafer tray, the clamping member is used to clamp the wafer. The clamping member is also provided with a pressing member. A limiting member is sleeved on the outer periphery of the chuck pin and connected to the chuck seat. The limiting member is used to limit the up and down position of the replacement part when it rotates. A drive mechanism for driving the chuck holder to rotate about its axis and for driving the chuck pin to rotate about the axis of the wafer holder.

2. The stable wafer chuck according to claim 1, characterized in that, The limiting member has a first thread on its inner circumference and the clamping member has a second thread on its outer circumference, and the first thread and the second thread cooperate with each other.

3. The stable wafer chuck according to claim 2, characterized in that, The inner circumference of the limiting member is provided with a sliding groove that is spirally distributed along its inner circumference, and the outer surface of the wafer holder is provided with a key, which cooperates with the sliding groove.

4. The stable wafer chuck according to claim 1, characterized in that, The upper end of the fixing part is provided with a protrusion, and the lower end of the replacement part is provided with a first groove, the first groove matching the shape of the protrusion of the fixing part.

5. The stable wafer chuck according to claim 1, characterized in that, The lower end of the replacement part is fixedly connected to a spring, and the inner diameter of the spring is larger than the outer diameter of the protrusion of the fixing part.

6. The stable wafer chuck according to claim 4, characterized in that, The protrusion is provided with ribs, and the inner surface of the first groove is provided with a second groove, the shape of which matches the ribs.

7. The stable wafer chuck according to claim 1, characterized in that, The pressing component consists of several pressing bars.

8. The stable wafer chuck according to claim 1, characterized in that, The maximum distance between the center of the wafer holder and the center of the chuck is greater than the radius of the wafer.

9. The stable wafer chuck according to claim 1, characterized in that, The upper surface of the chuck seat is a conical surface.

10. The stable wafer chuck according to claim 9, characterized in that, The angle between the generatrix of the cone and the horizontal plane is 2~5°.

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