Edge adsorption clamping structure applied to wafer probe station

Abstract

The invention discloses an edge adsorption clamping structure applied to a wafer probe station, and relates to the technical field of wafer processing, an adsorption platform serves as a key structure, a spiral air groove is formed in the center of the adsorption platform, distribution air grooves are formed in an annular area, and the spiral air groove is provided with through air grooves and semi-ventilation grooves which are distributed in a staggered mode. The fixed mounting platform is provided with a servo motor and a negative pressure adsorption system, the negative pressure adsorption system comprises a first negative pressure adsorption assembly, a second negative pressure adsorption assembly and a negative pressure detection unit, and through the combined design of center spiral gradual change adsorption and edge annular precise adsorption, and in cooperation with a linkage mechanism of negative pressure detection, servo regulation and air path self-adaption, the negative pressure detection is achieved; according to the technical scheme, dynamic and accurate regulation and control of the adsorption force are achieved, the technical problems that in a traditional adsorption clamping mode, the adsorption force is not uniform, and the wafer is prone to local deformation and transverse movement are solved, mechanical damage is avoided to the maximum extent while the wafer adsorption stability is guaranteed, and a reliable clamping basis is provided for wafer probe detection.

Description

Technical Field

[0001] This invention relates to the field of wafer fabrication technology, and more specifically to an edge adsorption clamping structure applied to a wafer probe station. Background Technology

[0002] In wafer probe testing, the wafer fixation process is one of the key factors affecting the test data. Considering the wafer material, adsorption positioning is the primary method. Refer to the relevant technical issues in document CN101261283A, where it is necessary to add the following: 1. It is essential to ensure the stability of the adsorption force. If it is too large, it will aggravate the mechanical damage to the wafer, such as exacerbating micro-deformation problems like local warping of the wafer. If it is too small, it will not be able to meet the adsorption stability requirements. 2. Secondly, the key point is the distribution of the adsorption force. Edge adsorption should avoid most of the central area of ​​the wafer. The adsorption force should be applied mainly at the edge of the wafer (ring band) to reduce the degree of constraint such as warping and bending caused by the wafer's own weight and internal stress. However, if the adsorption force between the ring band and the central area is too high, the mechanical damage and local deformation problems mentioned above will also occur, and even the wafer may experience local lateral displacement during actual operation.

[0003] In light of the above problems, this invention proposes a solution to these issues. Summary of the Invention

[0004] The purpose of this invention is to provide an edge adsorption clamping structure for use on a wafer probe station. Considering the adsorption and fixation method during the wafer probe detection process, it is necessary to ensure the stability of the wafer during the adsorption and fixation process, and also to avoid the local deformation process of the wafer.

[0005] The objective of this invention can be achieved through the following technical solution: an edge adsorption clamping structure applied to a wafer probe station, including a housing and a detection action component and an axial action component disposed inside the housing, with an installation platform, a fixed mounting platform and an adsorption platform disposed along the axial action component; The central area of ​​the upper surface of the adsorption platform is provided with a spiral air groove and the annular area is provided with a distribution air groove. The lower surface of the fixed platform is equipped with a servo motor corresponding to the adsorption platform and a negative pressure adsorption system corresponding to the spiral air groove and the distribution air groove. The spiral-shaped air groove has through air grooves and semi-through air grooves that are staggered.

[0006] The mounting platform is further configured such that it is installed at the output end of the axial motion component, and the fixed mounting platform and the mounting platform are fixedly connected.

[0007] The mounting platform is further configured such that it is installed at the output end of the axial motion component, and the fixed mounting platform and the mounting platform are fixedly connected.

[0008] The setting is further configured such that the length of the semi-ventilated groove is equal to the difference in helical radius between the spiral grooves.

[0009] The configuration is further defined as follows: the distribution gas grooves are arranged in a circular array along the center point of the adsorption platform, and the distribution gas grooves are composed of arc-shaped gas grooves corresponding to the circular contour of the adsorption platform and linear gas grooves corresponding to the diameter direction of the adsorption platform. The arc-shaped gas grooves and the linear gas grooves are each provided with a matching slider to maintain a sliding connection.

[0010] The configuration is further defined as follows: one end of the linear air groove is connected to the outermost edge of the spiral air groove by an air exchange groove, and the other end of the linear air groove is connected to the arc-shaped air groove by a narrow air groove.

[0011] The configuration is further defined as follows: the aligning sliders in the arc-shaped air groove are arranged in a mirror-symmetric manner along the position of the linear air groove, and irregularly shaped air ports are opened inside the arc-shaped air groove along the positions of the two aligning sliders.

[0012] The further configuration is as follows: the fixed mounting platform is equipped with an adsorption port corresponding to the irregularly shaped air port, and the diameter of the adsorption port is staggered with that of the irregularly shaped air port.

[0013] The system is further configured such that: the negative pressure adsorption system includes a first negative pressure adsorption component corresponding to the spiral-shaped air groove, a second negative pressure adsorption component corresponding to the distribution air groove, and a negative pressure detection unit corresponding to the first negative pressure adsorption component and the second negative pressure adsorption component. The negative pressure detection unit obtains the negative pressure value in the first negative pressure adsorption component and the second negative pressure adsorption component, and controls the servo motor to drive the adsorption platform to rotate at a fixed angle along the fixed mounting platform based on the obtained negative pressure value.

[0014] The present invention has the following beneficial effects: 1. The composite gas groove structure design adopts a central spiral gradient adsorption + edge annular precision adsorption. The central spiral gas groove achieves a gradient attenuation of adsorption force from the center to the outer edge through staggered through gas grooves and semi-through gas grooves, avoiding wafer warping caused by excessive concentration of adsorption force at the center. The edge distribution gas grooves focus on the wafer annular band for adsorption, which not only avoids bending and deformation problems caused by wafer self-weight and internal stress, but also reserves sufficient operating space for probe detection. At the same time, the gas exchange groove realizes the interconnection of the gas path between the center and the edge, eliminating the adsorption force deviation between the center and the edge from the structural level. It solves the pain points of easy local lateral movement and mechanical damage of wafers in traditional adsorption methods, and takes into account both adsorption stability and wafer surface protection. 2. Further construct an intelligent linkage control mechanism of negative pressure detection, servo control, and gas path self-adaptation. The negative pressure detection unit collects center and edge negative pressure data in real time. The servo motor can accurately drive the adsorption platform to rotate at a fixed angle according to the negative pressure value, and finely adjust the gas path diameter to dynamically adjust the adsorption force. With the adaptive sliding of the matching slider and the staggered distribution of irregular gas ports and adsorption gas ports, it can not only adapt the adsorption force parameters in real time according to the wafer material and specifications to avoid the problem of excessive or insufficient adsorption force, but also automatically compensate the gas path when there is a slight contour deviation at the edge of the wafer to ensure uniform application of edge adsorption force. At the same time, this control process does not affect the normal operation of axial detection. On the basis of achieving precise and dynamic control of adsorption force, it ensures the continuity and accuracy of wafer probe detection. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the edge adsorption clamping structure proposed in this invention for use on a wafer probe station; Figure 2 This is a schematic diagram of the internal structure of the shell in this invention; Figure 3 This is a schematic diagram of the axial motion component in the present invention; Figure 4 This is a top view of the adsorption platform in this invention; Figure 5 For the present invention Figure 4 A schematic diagram of the structure of part A.

[0017] In the diagram: 1. Housing; 2. Detection and motion assembly; 3. Axial motion assembly; 4. Adsorption platform; 5. Mounting platform; 301. Mounting platform; 6. Distribution air groove; 601. Arc-shaped air groove; 602. Alignment slider; 603. Irregularly shaped air inlet; 604. Linear air groove; 605. Air exchange groove; 7. Spiral air groove; 701. Through air groove; 702. Semi-through air groove. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1: This example addresses the technical problems that traditional negative pressure adsorption clamping methods in wafer probe inspection are prone to, such as uneven adsorption force, local wafer deformation, and excessive deviation of the adsorption force between the annular zone and the central area during edge adsorption, leading to wafer lateral movement and mechanical damage. It proposes a basic solution for an edge adsorption clamping structure for wafer probe stations. This structure is mainly used in the probe station inspection process in the semiconductor wafer processing field. It can directly connect to the detection action components and axial drive structure of the probe station to achieve stable adsorption and precise positioning of the wafer, providing a reliable clamping foundation for probe inspection. The system includes a detection motion component 2 and an axial motion component 3. Along the transmission direction of the axial motion component 3, a mounting platform 301, a fixed mounting platform 5, and an adsorption platform 4 are sequentially arranged. The mounting platform 301 is fixedly installed at the output end of the axial motion component 3. The fixed mounting platform 5 is fixedly connected to the mounting platform 301 and moves axially synchronously with the mounting platform 301. The upper surface of the adsorption platform 4 has a spiral-shaped air groove 7 in its central area and a distribution air groove 6 arranged in a circular array in its annular area. The spiral-shaped air groove 7 has a spiral structure along the downward direction of the adsorption platform 4, and it contains staggered through air grooves 701 and semi-through air grooves 702. The lower surface of the fixed mounting platform 5 is equipped with a servo motor adapted to the adsorption platform 4 and a negative pressure adsorption system corresponding to the spiral-shaped air groove 7 and the distribution air groove 6, providing negative pressure power for adsorption clamping.

[0020] The basic operation process of this embodiment is as follows: The wafer to be tested is placed on the upper surface of the adsorption platform 4. The negative pressure adsorption system is started, and the spiral air groove 7 and the distribution air groove 6 are evacuated to form a negative pressure inside the air groove. The atmospheric pressure is used to tightly adhere the wafer to the surface of the adsorption platform 4, completing the basic adsorption clamping. The axial motion component 3 drives the fixed mounting platform 5, the adsorption platform 4 and the wafer to move axially in a directional manner through the mounting platform 301, and cooperates with the detection motion component 2 to complete the probe detection operation of the wafer.

[0021] Among them, the spiral design of the spiral gas groove 7 enables flexible adsorption in the central region of the wafer. Unlike the full-coverage adsorption of traditional grid-shaped gas grooves, the spiral gas groove only forms a gradually changing adsorption force distribution in the central region, avoiding wafer warping caused by excessive adsorption force in the central region. The staggered distribution of through gas grooves 701 and semi-through gas grooves 702 further refines the adsorption gas path in the central region. One through gas groove 701 completely penetrates the region with the largest spiral diameter in the spiral gas groove 7 and its length is equal to the maximum spiral radius of the spiral gas groove 7. The spiral diameter regions penetrated by the other through gas grooves 701 decrease along the annular direction of the adsorption platform 4. The length of the semi-through gas groove 702 is equal to the difference in spiral radius of the spiral gas groove 7. Its essence can be referred to as the difference in spiral radius in a spiral line, such as... Figure 4The longest through-channel 701 is located at the center of the adsorption platform 4, while the other end is connected to the outermost spiral 7. The other through-channels 701 gradually "shorten" outward from the center of the adsorption platform 4, with each "shortening" length equal to the difference in spiral radius of the spiral 7. The length of the semi-through-channel 702 is equal to the maximum spiral radius of the spiral 7. This structure allows the adsorption force in the central area to be distributed in a gradient from the inside to the outside, effectively reducing the adsorption force deviation between the wafer center and the edge. Since the starting point of the negative pressure adsorption system corresponding to the spiral 7 is located at the center of the adsorption platform 4, when the negative pressure adsorption begins, the negative pressure adsorption force is first balanced along the longest through-channel 701. Then, the negative pressure adsorption force is balanced again using the other through-channels 701 and semi-through-channels 702. The key purpose is to avoid excessive concentration of negative pressure adsorption at the wafer center, which would exacerbate its weight. The distribution gas groove 6 focuses on the ring adsorption at the edge of the wafer, avoiding the central area of ​​the wafer, and only forms a stable clamping force in the ring band at the edge, reducing deformation problems such as warping and bending caused by the wafer's own weight and internal stress. At the same time, the edge adsorption design also reserves sufficient operating space for probe detection, avoiding interference between the gas groove and the adsorption structure and the probe detection. The basic structure adopts a combination design of "central spiral gradient adsorption + edge ring precise adsorption".

[0022] Example 2: This example is based on Example 1, with further design and optimization of the adsorption clamping structure. By refining the structure of the distribution gas groove 6, structural components such as the matching slider 602, the irregularly shaped gas port 603, and the air exchange groove 605 are added. At the same time, the composition and linkage control logic of the negative pressure adsorption system are optimized, forming a collaborative dynamic adjustment structure of adsorption force with the servo motor and the spiral gas groove 7. The adsorption force distribution can be adjusted in real time according to the wafer specifications and adsorption state, further improving the stability and accuracy of wafer adsorption. The distribution gas groove 6 consists of an arc-shaped gas groove 601 corresponding to the annular contour of the adsorption platform 4 and a linear gas groove 604 corresponding to the diameter direction of the adsorption platform 4. Both the arc-shaped gas groove 601 and the linear gas groove 604 have a sliding contact slider 602 inside them. One end of the linear gas groove 604 is connected to the outermost part of the spiral gas groove 7 via a gas exchange groove 605, and the other end is connected to the arc-shaped gas groove 601 via a narrow gas groove, thus achieving gas path communication between the central spiral gas groove 7 and the edge distribution gas groove 6. The contact slider 602 in the arc-shaped gas groove 601 moves along the linear gas groove 601. The positions of 04 are mirror-symmetrically distributed, and the arc-shaped air groove 601 has irregularly shaped air ports 603 along the positions of the two matching sliders 602. It should be added that: in order to ensure the sealing of the matching slider 602 during the sliding process, the matching slider 602 can be made of rubber material with high sealing performance. Furthermore, in order to ensure the sealing of the adsorption platform 4 and the fixed mounting platform 5 during the rotation process, sealing structures such as sealing strips can be added to the external areas of key parts such as the arc-shaped air groove 601, the linear air groove 604 and the spiral air groove 7 to ensure the sealing integrity of the air path. The mounting platform 5 is equipped with adsorption ports corresponding to the irregularly shaped air inlets 603. The diameter of the adsorption ports is staggered with that of the irregularly shaped air inlets 603 to avoid a sudden increase in local adsorption force caused by direct docking of the air inlets. The negative pressure adsorption system is upgraded to a multi-component linkage structure, including a first negative pressure adsorption component corresponding to the spiral air groove 7, a second negative pressure adsorption component corresponding to the distribution air groove 6, and a negative pressure detection unit that connects the two adsorption components at the same time. The negative pressure detection unit can obtain the negative pressure value in the first and second negative pressure adsorption components in real time and transmit the negative pressure signal to the control terminal of the servo motor. By controlling the change of the negative pressure value, the servo motor drives the adsorption platform 4 to rotate in a directional and fixed angle along the mounting platform 5.

[0023] The detailed operation process of this embodiment is as follows: S1: After the wafer is placed on the surface of the adsorption platform 4, the first negative pressure adsorption component draws air from the spiral-shaped air groove 7, forming a gradient negative pressure adsorption in the central region of the wafer. The airflow is diverted through the through air groove 701 and the semi-through air groove 702, so that the central adsorption force gradually decreases from the spiral center to the outer edge. The second negative pressure adsorption component draws air from the distribution air groove 6, and the airflow is interconnected with the airflow of the spiral-shaped air groove 7 through the linear air groove 604 and the air exchange groove 605, so that the adsorption force of the edge ring band and the adsorption force of the central region are flexibly connected, avoiding excessive adsorption force deviation between the two. The staggered distribution of the irregularly shaped air port 603 and the adsorption air port allows the edge adsorption force to act evenly on the wafer ring band. With the sliding of the matching slider 602 in the air groove, the air passage diameter can be finely adjusted according to the contour of the wafer edge (or it can be understood as the air passage cross-section / volume has differences), thereby changing the negative pressure adsorption force and further ensuring the uniformity of the edge adsorption force. S2: Throughout the entire adsorption and clamping process, the negative pressure detection unit continuously collects the real-time negative pressure values ​​of the first and second negative pressure adsorption components. This part can use the negative pressure detection system currently used in wafer negative pressure adsorption. When the negative pressure value in the central area is detected to be too high (which can easily cause wafer center deformation), the negative pressure detection unit sends a signal to the servo motor. The servo motor drives the adsorption platform 4 to rotate at a small angle, so that the air passage diameter of the spiral air groove 7 is finely adjusted, reducing the pumping efficiency in the central area and achieving precise downward adjustment of the negative pressure value. When the negative pressure value in the edge area is detected to be too low (which can easily cause wafer lateral movement), the servo motor drives the adsorption platform 4 to rotate, so that the overlapping area of ​​the distribution air groove 6 and the adsorption air port on the fixed mounting platform 5 is increased, improving the pumping efficiency in the edge area and achieving precise upward adjustment of the negative pressure value. When the deviation between the negative pressure in the center and the edge is detected to exceed the preset range, the servo motor rotates at a fixed angle to simultaneously finely adjust the air passage diameter of the spiral air groove 7 and the distribution air groove 6, so that the adsorption force of the two is restored to a balanced state. S3: And refer to Figure 5 The air exchange groove 605 between the linear air groove 604 and the spiral air groove 7 enables dynamic interconnection between the center and the edge air paths. When the negative pressure value on one side changes, the airflow can be flexibly compensated between the two air grooves through the air exchange groove 605, avoiding sudden changes in adsorption force caused by sudden rises and falls in negative pressure within a single air groove. The alignment slider 602 can slide autonomously within the air groove according to changes in airflow pressure, adaptively adjusting the diameter of the air groove. When there is a slight contour deviation at the edge of the wafer, the alignment slider 602 can block the excessively wide air groove area, ensuring uniform application of edge adsorption force and preventing the wafer from shifting laterally due to a lack of local adsorption force. When the axial motion component 3 drives the adsorption platform 4 and the wafer to move axially, the relative position between the adsorption platform 4 and the fixed mounting platform 5 remains stable. The servo motor only makes small-angle rotation adjustments when the adsorption force distribution is abnormal, which does not affect the axial detection action. After the detection is completed, the negative pressure adsorption system stops pumping air, the air tank returns to normal pressure, and the wafer can be easily removed, completing the entire adsorption clamping and detection process.

[0024] In summary, the linkage mechanism of "negative pressure detection - servo control - air path self-adaptation" throughout the entire operation process achieves dynamic and precise control of the adsorption force, ensuring that the adsorption force always adapts to the material characteristics and specifications of the wafer. This not only guarantees the stability of wafer clamping but also minimizes mechanical damage and local deformation caused by excessive adsorption force. The combination of central spiral gradient adsorption and edge annular precise adsorption, along with the interconnection and compensation of the air path, structurally eliminates the adsorption force deviation between the center and the edge, solving the technical problems of wafer lateral movement and deformation in traditional edge adsorption.

[0025] The above description is merely an example and illustration of the structure of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the structure of the invention, they should all fall within the protection scope of the present invention.

[0026] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," 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 the invention. In this specification, 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 may be combined in any suitable manner in one or more embodiments or examples.

[0027] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. An edge adsorption clamping structure for a wafer probe station, comprising a housing (1) and a detection action component (2) and an axial action component (3) disposed inside the housing (1), characterized in that, The axial motion assembly (3) is provided with an installation platform (301), a fixed mounting platform (5), and an adsorption platform (4); The adsorption platform (4) has a spiral air groove (7) in the central area of ​​the upper surface and a distribution air groove (6) in the annular area. The fixed platform (5) has a servo motor corresponding to the adsorption platform (4) and a negative pressure adsorption system corresponding to the spiral air groove (7) and the distribution air groove (6) installed on the lower surface. The spiral-shaped air groove (7) has through air grooves (701) and semi-through air grooves (702) that are staggered.

2. The edge adsorption clamping structure applied to a wafer probe station according to claim 1, characterized in that, The mounting platform (301) is installed at the output end of the axial motion component (3), and the fixed mounting platform (5) is fixedly connected to the mounting platform (301).

3. The edge adsorption clamping structure applied to a wafer probe station according to claim 1, characterized in that, The spiral-shaped air groove (7) is spiral in its downward direction. The through air groove (701) and the semi-through air groove (702) are arranged along the diameter direction of the adsorption platform (4). One of the through air grooves (701) completely penetrates the maximum spiral diameter area in the spiral-shaped air groove (7) and its length is equal to the maximum spiral radius of the spiral-shaped air groove (7). The spiral diameter area penetrated by the other multiple through air grooves (701) decreases along the annular direction of the adsorption platform (4).

4. The edge adsorption clamping structure applied to a wafer probe station according to claim 1, characterized in that, The length of the semi-ventilated groove (702) is equal to the difference in spiral radius between the spiral groove (7) and the semi-ventilated groove (7).

5. The edge adsorption clamping structure applied to a wafer probe stage according to claim 1, characterized in that, The distribution gas grooves (6) are arranged in a ring array along the center point of the adsorption platform (4), and the distribution gas grooves (6) are composed of arc-shaped gas grooves (601) corresponding to the ring contour of the adsorption platform (4) and linear gas grooves (604) corresponding to the diameter direction of the adsorption platform (4). The arc-shaped gas grooves (601) and the linear gas grooves (604) are both provided with a matching slider (602) to maintain a sliding connection.

6. The edge adsorption clamping structure for a wafer probe stage according to claim 5, characterized in that, One end of the linear air groove (604) is connected to the outermost part of the spiral air groove (7) by an air exchange groove (605), and the other end of the linear air groove (604) is connected to the arc-shaped air groove (601) by a narrow air groove.

7. The edge adsorption clamping structure applied to a wafer probe stage according to claim 6, characterized in that, The positioning sliders (602) in the arc-shaped air groove (601) are arranged in a mirror symmetrical manner along the setting position of the linear air groove (604), and irregularly shaped air ports (603) are opened inside the arc-shaped air groove (601) along the setting positions of the two positioning sliders (602).

8. The edge adsorption clamping structure applied to a wafer probe station according to claim 7, characterized in that, The mounting platform (5) is equipped with an adsorption port corresponding to the irregularly shaped air port (603), and the diameter of the adsorption port is staggered with that of the irregularly shaped air port (603).

9. The edge adsorption clamping structure for a wafer probe stage according to claim 8, characterized in that, The negative pressure adsorption system includes a first negative pressure adsorption component corresponding to the spiral air groove (7), a second negative pressure adsorption component corresponding to the distribution air groove (6), and a negative pressure detection unit corresponding to the first negative pressure adsorption component and the second negative pressure adsorption component. The negative pressure detection unit obtains the negative pressure value in the first negative pressure adsorption component and the second negative pressure adsorption component. The obtained negative pressure value controls the servo motor to drive the adsorption platform (4) to rotate at a fixed angle along the fixed mounting platform (5). In the initial state, the minimum arc of the matching slider (602) in the arc-shaped air groove (601) relative to one end of the arc-shaped air groove (601) is C°. The rotation angle range of the adsorption platform (4) is -C° to C°.

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