Chuck assembly and measuring device

Abstract

The application provides a chuck assembly and a measuring device. The chuck assembly comprises a chuck, a plurality of support columns for supporting a wafer are arranged on one side of the chuck facing the wafer, and a plurality of air nozzles capable of forming an air cushion are arranged on the side of the chuck. The plurality of support columns form a plurality of concentric support rings with the rotation center of the chuck as the center. The plurality of air nozzles form a plurality of concentric air nozzle rings with the rotation center as the center. At least one support ring is arranged between any two adjacent air nozzle rings. In the embodiment of the application, the chuck assembly can effectively improve the anti-interference ability, the test stability, and the measurement accuracy.

Description

Technical Field

[0001] This application relates to the field of wafer measurement technology, specifically to a chuck assembly and a measurement device. Background Technology

[0002] A wafer is a silicon wafer used in the fabrication of silicon semiconductor integrated circuits; it is the raw material in chip production. During wafer fabrication or measurement, a chuck assembly is used to hold the wafer. Wafer manufacturing and measurement technologies are receiving increasing attention. The demand for the stability, efficiency, and accuracy of the chuck assemblies used to hold wafers is growing.

[0003] Currently, the main problems with the measurement device include weak anti-interference performance, insufficient stability, inadequate measurement accuracy, long loading / unloading time for wafers, and difficulty in predicting the accuracy of test results. Summary of the Invention

[0004] In view of this, the embodiments of this application aim to provide a measuring device to improve the problems of weak anti-interference performance, insufficient stability and low measurement accuracy in the prior art.

[0005] This application provides a chuck assembly according to one embodiment. The chuck assembly includes a main chuck, with support pillars for supporting the wafer and multiple air nozzles for forming an air cushion on the side of the main chuck facing the wafer. The support pillars form multiple concentric support rings with the rotation center of the main chuck as the center, and the air nozzles form multiple concentric air nozzle rings with the rotation center as the center. At least one support ring is spaced between any two adjacent air nozzle rings. In one embodiment of this application, the support pillars located on the same support ring are circumferentially evenly distributed, and the spacing between any two adjacent support rings is equal.

[0006] In one embodiment of this application, the distance ΔT between any two circumferentially adjacent support columns and the distance ΔR between any two adjacent support rings are in a predetermined ratio.

[0007] In one embodiment of this application, the set ratio is set as follows:

[0008] ΔT / ΔR=2πn / N=2π / m

[0009] Where ΔT is the distance between two circumferentially adjacent support columns; ΔR is the distance between any two adjacent support rings; N is the number of support columns corresponding to each support ring; n is a natural number, referring to the sequence number of each support ring arranged from the inside out among multiple support rings; m refers to the number of support columns on the support ring with the smallest radius.

[0010] In one embodiment of this application, m is an even number.

[0011] In one embodiment of this application, m is 6.

[0012] In one embodiment of this application, ΔT and / or ΔR are not greater than 6 mm.

[0013] In one embodiment of this application, a plurality of support pillars are symmetrically distributed on the side of the main chuck facing the wafer.

[0014] In one embodiment of this application, a plurality of air nozzles are symmetrically distributed on the side of the main chuck facing the wafer.

[0015] In one embodiment of this application, the air nozzle is configured as follows:

[0016] ΔT' / ΔR'=2πn' / N'=2π / m'

[0017] Where ΔT' is the distance between two circumferentially adjacent nozzles; ΔR' is the distance between any two adjacent nozzle rings; N' is the number of nozzles on each nozzle ring; n' is a natural number, referring to the sequence number of each nozzle ring arranged from the inside out among multiple nozzle rings; and m' refers to the number of nozzles on the nozzle ring with the smallest radius.

[0018] In one embodiment of this application, the difference between ΔT' and ΔR' is less than 8 mm.

[0019] In one embodiment of this application, the main chuck includes a plurality of sub-chucks, the plurality of sub-chucks including a first sub-chuck for supporting a wafer, the support post being located on the side of the first sub-chuck facing the wafer; a second sub-chuck fixedly attached to the side of the first sub-chuck away from the wafer; and a third sub-chuck fixedly attached to the side of the second sub-chuck away from the wafer; wherein the first sub-chuck and the second sub-chuck define a first chamber, the second sub-chuck and the third sub-chuck define a second chamber, and the air nozzle is disposed on the side of the first sub-chuck facing the wafer, the air nozzle including a first air nozzle and a second air nozzle, wherein the first air nozzle communicates with the first chamber, and the second air nozzle communicates with the second chamber.

[0020] In one embodiment of this application, multiple sub-chucks are assembled to form a main chuck module.

[0021] In one embodiment of this application, the first chamber and the second chamber are independent of each other.

[0022] In one embodiment of this application, the first air nozzle and the second air nozzle are arranged alternately in the radial direction.

[0023] In one embodiment of this application, a first air nozzle and a second air nozzle are arranged alternately in the circumferential direction on the same air nozzle ring.

[0024] In one embodiment of this application, a first outer sealing ring is provided on the side of the main chuck facing the wafer, which is concentric with the support ring and disposed on the outer periphery of the main chuck. The top surface of the first outer sealing ring and the top surface of the support column are in the same plane, and the flatness is not greater than 8μm.

[0025] In one embodiment of this application, the first outer sealing ring is provided with an opening groove that radially penetrates the wall of the first outer sealing ring.

[0026] In one embodiment of this application, an annular support platform is further provided on the side of the main chuck facing the wafer, which is fitted around the outer periphery of at least three second air nozzles, and the annular support platform is evenly distributed along the circumference of the rotation center.

[0027] In one embodiment of this application, the chuck assembly has a first inlet / outlet communicating with a first chamber and a second inlet / outlet communicating with a second chamber; the chuck assembly also has a first adjustment unit, which is connected to the outlet of the first inlet / outlet to control at least one of the pressure, flow rate, and flow rate at the first gas outlet; the chuck assembly also has a second adjustment unit, which is connected to the second inlet / outlet to control at least one of the pressure, flow rate, and flow rate at the second inlet / outlet to adjust the characteristics of the air cushion.

[0028] In one embodiment of this application, the chuck assembly includes a support, and the chuck and the support are detachably connected.

[0029] In one embodiment of this application, the support includes a fixed frame and a movable frame connected to the fixed frame. The support also includes an adjustment mechanism for adjusting the tilt angle of the movable frame, with one end of the adjustment mechanism connected to the fixed frame and the other end connected to the movable frame.

[0030] In one embodiment of this application, the movable frame includes a first support plate and a second support. The first support plate is rotatably mounted on the side of the support plate facing the main chuck, and the main chuck is detachably mounted on the first support plate.

[0031] A second aspect of this application provides a measuring device, which includes any of the chuck assemblies described above.

[0032] In one embodiment of this application, the measuring device includes an optical imaging component disposed on the side of the wafer away from the master chuck.

[0033] The air nozzles on this chuck assembly can be configured as needed. When wafer levitation is required, a second air nozzle and / or a first air nozzle can be used simultaneously to adjust the air cushion and float the wafer on it for measurements such as wafer flatness and warpage. The support column can support the wafer even when the air cushion's strength is insufficient, thus preventing wafer concavity and improving measurement accuracy. Through these configurations, the chuck assembly of this application effectively improves anti-interference capabilities, ensures stable measurement performance, and significantly enhances measurement accuracy. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the structure of a chuck assembly provided in an embodiment of this application.

[0035] Figure 2 for Figure 1 A cross-sectional structural diagram of the provided chuck assembly.

[0036] Figure 3 for Figure 1 A schematic diagram of the support column distribution on the first sub-chuck.

[0037] Figure 4 for Figure 3 A schematic diagram of the arrangement of the opening grooves on the first outer sealing ring.

[0038] Figure 5 for Figure 1 A schematic diagram showing the distribution of the first and second air nozzles on the first sub-chuck.

[0039] Figure 6 yes Figure 5 A magnified view of a portion of the image.

[0040] Figure 7 for Figure 1 A schematic diagram of the structure of the second sub-chuck facing the wafer.

[0041] Figure 8 for Figure 1 A schematic diagram of the structure of the second sub-chuck on the side furthest from the wafer.

[0042] Figure 9 for Figure 1 A schematic diagram of the structure of the third sub-chuck facing the wafer.

[0043] Figure 10 This is a schematic diagram of the structure of a support provided in one embodiment of this application.

[0044] Figure 11 This is a cross-sectional structural diagram of a chuck assembly provided in another embodiment of this application. Detailed Implementation

[0045] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0046] like Figures 1-2 As shown, this application discloses a chuck assembly, which includes a main chuck 1. The main chuck 1 has support pillars 111 for supporting the wafer and multiple air nozzles for forming an air cushion on the wafer-facing side. The support pillars 111 form multiple concentric support rings with the rotation center of the main chuck 1 as the center, and the air nozzles form multiple concentric air nozzle rings with the rotation center as the center. At least one support ring is spaced between any two adjacent air nozzle rings. The air nozzles on the main chuck can be configured as needed: when suspending the wafer, all nozzles can be pressure nozzles capable of ejecting a first gas onto the wafer, or both pressure nozzles and vacuum nozzles capable of guiding a second gas from the wafer towards the main chuck can be used simultaneously to adjust the air cushion and float the wafer on it for measurement, such as measuring the wafer's flatness or warpage; when adsorbing the wafer, all nozzles can be vacuum nozzles. The support pillars on this master chuck can provide support to multiple wafers during measurement, reducing axial deformation. For example, if the gas cushion's strength is insufficient to support the wafer, the wafer is supported by numerous support pillars, preventing wafer dent and thus improving measurement accuracy. When all gas nozzles are vacuum nozzles, the support pillars prevent excessive wafer collapse by supporting the wafer. When some gas nozzles are pressure nozzles and some are vacuum nozzles, the gas cushion can automatically adjust under the combined action of the vacuum and pressure nozzles as follows: the first gas ejected from the pressure nozzle allows the wafer to float on the surface of the master chuck. When the first gas encounters the wafer and is obstructed, it flows back to the master chuck, forming a second gas that flows out through the vacuum nozzle. As the wafer moves away from the master chuck, the pressure between the wafer and the master chuck decreases, and the wafer moves closer to the master chuck under the suction of the vacuum nozzle. As the wafer moves closer to the master chuck, the pressure between the wafer and the master chuck gradually increases, causing the wafer to move away from the master chuck, and this process repeats... This chuck assembly automatically keeps the wafer floating stably, greatly improving the wafer's anti-interference capability during testing. Furthermore, using the aforementioned main chuck eliminates the need for clamping tools when measuring the wafer, further reducing wafer deformation and thus improving measurement accuracy. Through these features, the chuck assembly of this application effectively improves anti-interference capability, ensures test stability, and significantly enhances measurement accuracy.

[0047] The cross-sectional shape of the air nozzle can be designed into any shape according to requirements.

[0048] The main chuck 1 has a wafer slot on the side facing the wafer to accommodate it. Generally, the diameter of the wafer slot is slightly smaller than the diameter of the wafer. The outermost support post 111 is typically positioned less than the distance between two adjacent support rings from the edge of the wafer slot. For example, when the distance between two support rings is approximately 4 mm, the distance between the outermost support post 111 and the edge of the wafer slot can be set to 2 mm-3 mm. Additionally, the outermost air nozzle is typically positioned less than the distance between two adjacent air nozzle rings from the edge of the wafer slot.

[0049] In one embodiment, to ensure balanced force on the wafer, support posts 111 located on the same support ring are evenly distributed circumferentially around the main chuck 1, and the spacing between any two adjacent support rings is equal. The cross-section of the support end of the support post 111 can be circular to match the side of the wafer facing the main chuck 1. Alternatively, the cross-section of the support end of the support post 111 can be annular. This creates an air cushion within the annular ring, reducing the contact stiffness between the support post 111 and the wafer, further protecting the wafer and improving measurement accuracy.

[0050] In another embodiment, such as Figure 3 As shown, the distance ΔT between two circumferentially adjacent support columns 111 and the distance ΔR between two radially adjacent support columns 111 are in a predetermined ratio. Here, the two radially adjacent support columns 111 are located on two adjacent support rings, respectively. The distance between the two circumferentially adjacent support columns 111 can be set as needed.

[0051] In one embodiment, the set ratio is set as follows: ΔT / ΔR=2πn / N=2π / m, where ΔT is the distance between two circumferentially adjacent support columns; ΔR is the distance between two radially adjacent support columns, which is the distance between any two adjacent support rings; N is the number of support columns corresponding to each support ring; n is a natural number, referring to the sequence number of each support ring in the multiple support rings arranged from the inside out; and m refers to the number of support columns on the support ring with the smallest radius.

[0052] To ensure symmetrical stress on the wafer, m is usually an even number.

[0053] In one embodiment, m is 6. In this embodiment, ΔT / ΔR≈1, at which point the distance between any two adjacent radial support pillars 111 and the distance between any two adjacent circumferential support pillars 111 are approximately equal, which enables the wafer to be subjected to uniform force at all points, thereby further improving the measurement accuracy of the wafer.

[0054] In another embodiment, ΔT and / or ΔR is no greater than 6 mm. This results in a relatively dense arrangement of the support pillars 111. When the wafer is supported in a suspended manner, if the air cushion strength between the wafer and the main chuck 1 is insufficient to fully support the wafer, causing the wafer to rest on the support pillars 111, the local stress on the wafer can be reduced, thus reducing the amount of local deformation. Furthermore, when the main chuck 1 supports the wafer using an adsorption method, this dense arrangement of support pillars 111 can flatten wafers with high spatial frequencies or high warpage, and reduce the impact on wafer flatness. Preferably, ΔT and / or ΔR is no greater than 4 mm.

[0055] In one embodiment, the support pillar 111 is configured as a small cylinder with a diameter of approximately 0.2 mm and a height of 15-25 μm. When the diameter of the wafer changes, the diameter and height of the support pillar 111 can be adjusted accordingly.

[0056] In another embodiment, multiple support posts 111 are axially symmetrically distributed on the side of the main chuck 1 facing the wafer. By symmetrically arranging the support posts 111, the wafer is subjected to symmetrical forces, preventing it from tilting due to asymmetrical forces, thus improving measurement accuracy. Of course, the support posts 111 may not be symmetrically distributed. The arrangement of the support points 111 on the main chuck 1 can take various forms, aiming for uniform distribution that conforms to the wafer's deformation characteristics to maximize the flatness of the wafer during measurement.

[0057] In another embodiment, see Figure 5 As shown, multiple air nozzles are symmetrically distributed on the side of the main chuck 1 facing the wafer. By symmetrically arranging the air nozzles, the wafer is subjected to symmetrical forces, preventing it from tilting due to asymmetrical forces and improving measurement accuracy. Of course, the multiple air nozzles can also be non-symmetrically distributed on the side of the main chuck 1 facing the wafer.

[0058] In another embodiment, the air nozzles are configured as follows: ΔT' / ΔR'=2πn' / N'=2π / m'. Here, ΔT' is the distance between two circumferentially adjacent air nozzles, ΔR' is the distance between any two adjacent air nozzle rings, N' is the number of air nozzles on each air nozzle ring, n' is a natural number representing the sequence number of each air nozzle ring arranged from the inside out among multiple air nozzle rings, and m' refers to the number of air nozzles on the air nozzle ring with the smallest radius. With the air nozzles on the main chuck 1 distributed according to this pattern, the force acting on the wafer is adjustable, and the force exerted on the wafer by the gas entering and exiting through the air nozzles is more uniform.

[0059] To ensure that the wafer under measurement experiences relatively uniform stress in all directions, in one embodiment, the difference between ΔT' and ΔR' is less than 8 mm. Preferably, the difference between ΔT' and ΔR' is less than 5 mm.

[0060] In one specific embodiment, m'=6, that is, ΔT' / ΔR'=2πn' / N'=2π / 6≈1, that is, the difference between ΔT' and ΔR' is approximately zero.

[0061] In another embodiment, see Figure 2 As shown, the main chuck 1 includes multiple sub-chucks, including a first sub-chuck 11 for supporting the wafer, with a support post 111 located on the side of the first sub-chuck 11 facing the wafer; a second sub-chuck 12 fixed to the side of the first sub-chuck 11 opposite to the wafer; and a third sub-chuck 13 fixed to the side of the second sub-chuck 12 opposite to the wafer. The first sub-chuck 11 and the second sub-chuck 12 define a first chamber 14, and the second sub-chuck 12 and the third sub-chuck 13 define a second chamber 15. All air nozzles are located on the side of the first sub-chuck 11 facing the wafer. That is, the first sub-chuck 11, the second sub-chuck 12, and the third sub-chuck 13 are coaxially arranged.

[0062] The air nozzles include a first air nozzle 112 and a second air nozzle 113 opening on the side of the first sub-chuck 11 facing the wafer. The first air nozzle 112 is connected to the first chamber 14, and the second air nozzle 113 is connected to the second chamber 15. Generally, the second air nozzle 113 is a pressure nozzle connected to a pressure gas source through the second chamber 15, and the first air nozzle 112 is a vacuum nozzle connected to an outlet through the first chamber 14. When both the first air nozzle 112 and the second air nozzle 113 are connected to the pressure gas source, both are pressure nozzles; when both the first air nozzle 112 and the second air nozzle 113 are connected to the outlet, both are vacuum nozzles.

[0063] By setting different first chambers 14 and second chambers 15, the main chuck 1 connects the first air nozzle 112 and the second air nozzle 113 to the first chambers 14 and the second chambers 15 respectively, thus optimizing the airflow in advance and ensuring that the pressure of all air nozzles is equal.

[0064] Specifically, the first chamber 14 and the second chamber 15 are independent of each other to ensure that the airflow flows in a set direction.

[0065] In another embodiment, multiple sub-chucks are assembled into a main chuck 1 to form a main chuck module. That is, the sub-chucks are connected in a non-detachable manner. With this configuration, the main chuck 1 forms a modular design, which has good stability, is easy to maintain, and can effectively reduce costs. Moreover, since the main chuck 1 is non-detachable after being assembled from multiple sub-chucks, when it is necessary to measure wafers of different specifications, the main chuck 1 of different specifications can be replaced as a whole. This reduces loading / unloading time and can effectively ensure installation accuracy, which is beneficial to improving the accuracy of test results.

[0066] In this embodiment, the multiple sub-chucks are preferably connected by adhesive bonding. This helps reduce stress deformation of the main chuck 1 and increases measurement accuracy.

[0067] The main chuck 1 is covered with alternating first gas nozzles 112 and second gas nozzles 113. Gas is supplied in layers from the first gas nozzles 112 and second gas nozzles 113. When wafer levitation is required, only the second gas nozzle 113 (as a pressure nozzle) can be used, or both the first gas nozzle 112 (as a vacuum nozzle) and the second gas nozzle 113 (as a pressure nozzle) can be used simultaneously. The performance of the gas nozzles in creating the air cushion can be adjusted for different scenarios. The main chuck 1 can float the wafer on the air cushion, and then various parameters, such as flatness and warpage, can be measured using an interferometer. The pressure in the first chamber 14 and the second chamber 15 can be adjusted as needed.

[0068] For example, in one embodiment, when both the first chamber 14 and the second chamber 15 are connected to a vacuum (i.e., connected to an outlet), all the gas nozzles can generate a vacuum, forming a vacuum cavity between the main chuck 1 and the wafer. The wafer is held in place on the side of the main chuck 1 facing the wafer, and the main chuck 1 has 2000-3000 evenly distributed support points 111 on this side, which can flatten the wafer under the support of the support points 111.

[0069] In another embodiment, when compressed gas (CDA) with a set pressure is introduced into the second chamber 15 to provide levitation force to the wafer, the wafer is suspended on the side of the main chuck 1 facing the wafer. At the same time, the first chamber 14 is connected to a vacuum, and compressed gas (CDA) with a set pressure is ejected from the second nozzle 113 to form a first gas. After the first gas touches the wafer, it forms a second gas and then flows back to the first chamber 14 along the first nozzle 12 to maintain the stability of the main chuck 1 when it is suspended. This can greatly improve the anti-interference ability of the wafer when it is being tested.

[0070] In this embodiment, the pressure in the first chamber 14 and the second chamber 15 is uniformly distributed, and the pressure in all gas nozzles is equal. This ensures uniform force during wafer adsorption or wafer levitation, guaranteeing test stability and improving test accuracy.

[0071] To meet different testing needs, the main chuck 1 can also be configured as a two-disc, one-cavity structure, see [link / reference]. Figure 11 As shown, the main chuck 1 has two sub-chucks, and a chamber is provided between the two sub-chucks. This chamber is connected to an air nozzle located on the side of the main chuck 1 facing the wafer.

[0072] In the above embodiments, the first air nozzle 112 and the second air nozzle 113 can be arranged on the chuck in various ways.

[0073] In one embodiment, the first air nozzle 112 and the second air nozzle 113 are arranged alternately in the radial direction. Specifically, they can be arranged in a pattern of alternating circles of the first air nozzle 112 and the second air nozzle 113.

[0074] In another embodiment, the first nozzle 112 and the second nozzle 113 are alternately arranged on the same nozzle ring. See [link to details]. Figure 5 As shown, the circumferential arrangement can be achieved by using a first air nozzle 112 spaced apart by a second air nozzle 113.

[0075] In another embodiment, see Figure 3 As shown, a first outer sealing ring 115 is provided on the side of the main chuck facing the wafer, concentric with the support ring and located on the outer periphery of the wafer slot. The first outer sealing ring 115 can form a space with the wafer and the wafer-facing side of the main chuck 1 to form a vacuum cavity in the vacuum adsorption test, so that the wafer can be adsorbed on the main chuck 1, or reduce the airflow from the outer periphery of the main chuck 1 in the suspension test, thereby facilitating the formation of an air cushion to support the wafer.

[0076] Specifically, the top of the first outer sealing ring 115 and the top of the support column 111 are kept on the same plane, and the flatness is no more than 8μm. This can prevent the wafer from collapsing excessively in the vacuum adsorption test, thereby further increasing the measurement accuracy.

[0077] Preferably, the top of the first outer sealing ring 115 and the top of the support column 111 are kept in the same plane and the flatness is no greater than 1 μm. In another embodiment, see... Figure 4 As shown, in order to reduce wafer edge warping, the first outer sealing ring 115 is provided with an opening groove 1151 that radially penetrates the first outer sealing ring 115 to release the vacuum force in the vacuum cavity formed by the first outer sealing ring 115, the wafer, and the main chuck 1 facing the wafer side during the vacuum adsorption experiment, thereby further increasing the measurement accuracy.

[0078] The opening groove 1151 is evenly distributed around the circumference of the first outer sealing ring 115 so that the vacuum force is released evenly, which can further increase the measurement accuracy.

[0079] Specifically, the axial depth of the opening slot 1151 in the main chuck 1 is generally set to 2-5 μm.

[0080] In another embodiment, see Figures 5-6 As shown, the first sub-chuck 11 is also provided with an annular support platform 114 concentric with the second air nozzle 113. Specifically, the outer diameter of the support platform 114 is set to 3 mm, and the height is set to 15~25 μm. The top surface of the support platform 114 and the top surface of the first sealing ring 115 can be located on the same plane, with a flatness of no more than 1 μm, so as to avoid excessive wafer collapse during vacuum adsorption tests.

[0081] In another embodiment, see Figure 2As shown, to prevent leakage from the first chamber 14, a sealing structure is provided between the first sub-chuck 11 and the second sub-chuck 12. Specifically, a second outer sealing ring 121 extending axially outward is provided on the side of the second sub-chuck 12 facing the first sub-chuck 11, and a first sealing groove 116 is provided on the first sub-chuck 11 to cooperate with the second outer sealing ring 121. The second outer sealing ring 121 is concentric with the second sub-chuck 12. The second outer sealing ring 121 and the first sealing groove 116 formed on the first sub-chuck 11 cooperate to form a sealing structure, preventing the first chamber 14 from leaking through the gap between the first sub-chuck 11 and the second sub-chuck 12. The second outer sealing ring 121 serves a sealing function, and also acts as the contact point for the bonding of the first sub-chuck 11 and the second sub-chuck 12, as well as a support to resist deformation, which can reduce the deformation of the main chuck 1 and improve the anti-interference ability.

[0082] In one embodiment, see Figure 7 As shown, a pressure sealing ring 123 is provided on the second sub-chuck 12. The pressure sealing ring 123 is a hollow columnar structure protruding from the bottom wall of the first chamber 14, i.e., the side of the second sub-chuck 12 facing the first sub-chuck 11. The second air nozzle 113 connects to the second chamber 15 through the hollow part of this columnar structure. The pressure sealing ring 123 serves as a sealing ring at the connection between the first sub-chuck 11 and the second sub-chuck 12, and also as a bonding contact point during assembly. It is a deformation-resistant support structure that reduces deformation of the main chuck 1 and improves anti-interference capabilities.

[0083] In this embodiment, see Figure 2 As shown, the first sub-chuck 11 is provided with a second sealing groove 117 that cooperates with the pressure sealing ring 123. The outer wall of the pressure sealing ring 123 abuts against the inner wall of the second sealing groove 117. The top of the pressure sealing ring 123 has an axial recess. The second sealing groove 117 is configured as an annular groove, and the middle part of the annular groove is a hollow columnar protrusion 118. When the first sub-chuck 11 and the second sub-chuck 12 are in the assembled state, the columnar protrusion 118 is accommodated in the axial recess on the pressure sealing ring 123. The hollow part of the columnar protrusion 118 connects to the second chamber 15 and the second air nozzle 113. In this way, the sealing quality can be further guaranteed and the connection between the first sub-chuck 11 and the second sub-chuck 12 can be made more stable, reducing the deformation of the main chuck 1 and improving the anti-interference ability.

[0084] In this embodiment, see Figure 7As shown, three annular support structures 124 are evenly distributed around the central circumference of the second sub-chuck 12. These three annular support structures 124 are respectively fitted onto three different pressure sealing rings 123. The annular support structures 124 serve as support points when the first sub-chuck 11 and the second sub-chuck 12 are glued together, ensuring that the first sub-chuck 11 and the second sub-chuck 12 are parallel to each other. The three annular support structures 124 are set to the same height. The height of the annular support structures 124 is less than the height of the pressure sealing rings 123.

[0085] In another embodiment, see Figure 9 As shown, the third sub-chuck 13 is provided with a support base 133 extending axially from the side of the third sub-chuck 13 toward the second sub-chuck 12. The side of the second sub-chuck 12 toward the third sub-chuck 13 is provided with a bonding hole 127 that matches the support base 133. The bonding hole 127 is coaxial with the first air nozzle 112. The bonding hole 127 is located on the side of the second sub-chuck 12 toward the third sub-chuck 13. In the installed state, the outer wall of the support base 133 abuts against the inner wall of the bonding hole 127. The bonding hole 127 is the bonding contact point and the support that resists deformation.

[0086] See Figure 2 As shown, in order to further enhance the connection stability of the second sub-chuck 12 and the third sub-chuck 13, the end of the support base 133 is axially recessed, a columnar structure is formed in the middle of the glue hole 127, and an annular groove is formed around the columnar structure. The columnar structure is accommodated in the axial recess at the end of the support base 133 in the installed state.

[0087] In another embodiment, a third outer sealing ring 131 is provided on the third sub-chuck 13. The third outer sealing ring 131 is located on the side of the third sub-chuck 13 facing the second sub-chuck 12, and the radius of the third outer sealing ring 131 is slightly smaller than the radius of the third sub-chuck 13. A sealing ring 125 that cooperates with the third outer sealing ring 131 is provided on the second sub-chuck 12. The third outer sealing ring 131 surrounds the circumference of the third sub-chuck 13 and cooperates with the sealing ring 125 formed on the second sub-chuck 12 to form a sealing structure. In this case, the third outer sealing ring 131 serves a sealing function and is also the contact point where the second sub-chuck 12 and the third sub-chuck 13 are bonded together, as well as a support to resist deformation.

[0088] The main chuck 1 is equipped with a first inlet / outlet. Under normal circumstances, the first inlet / outlet is connected to an air extraction device. Of course, it can also be connected to a pressurized air source as needed.

[0089] In the example above, all first air nozzles 112 are connected to the first chamber 14 via channels formed on the first sub-chuck 11. All second air nozzles 113 are connected to the second chamber 15 via first channels formed on the first sub-chuck 11 and second channels formed on the second sub-chuck 12, respectively.

[0090] In one embodiment, the first inlet / outlet is evenly distributed along the central circumference of the main chuck 1. Specifically, the main chuck 1 has three circumferentially distributed first inlets / outlets. These first inlets / outlets connect the first nozzles 112 to a vacuum device or a pressurized gas source (not shown in the figure) via a first chamber 14. For example, when all the first nozzles 112 are connected to a vacuum, the first inlets / outlets connect them to the vacuum device via the first chamber 14; when all the first nozzles 112 are connected to pressurized gas, the first inlets / outlets connect them to the pressurized gas source via a second chamber 15. In the above embodiment, three of the three first inlets / outlets and three of the multiple first nozzles 112 can be coaxial. The main chuck 1 may also have a second inlet / outlet, which is evenly distributed along the central circumference of the main chuck 1. This second inlet / outlet is generally connected to a pressurized gas source, but can also be connected to a vacuum device as needed. Specifically, the main chuck 1 is provided with three circumferentially distributed second inlets and outlets. These second inlets and outlets are used to connect the second gas nozzles 113 to a pressurized gas source or a vacuum pump (not shown in the figure) via the second chamber 15. For example, when all the second gas nozzles 113 are connected to a vacuum, the second inlets and outlets are used to connect the second gas nozzles 113 to the vacuum pump via the second chamber 15; when all the second gas nozzles 113 are connected to pressurized gas, the second inlets and outlets are used to connect the second gas nozzles 113 to the pressurized gas source via the second chamber 15.

[0091] In the above embodiment, three of the three second inlets and outlets and the plurality of second air nozzles 113 can be coaxial.

[0092] In one embodiment, the first inlet / outlet includes a through hole 129 disposed on the second sub-chuck 12 and a through hole 130 disposed on the third sub-chuck 13. The second inlet / outlet includes a through hole 136 disposed on the third sub-chuck 13.

[0093] A sealing ring 126 is also provided on the second sub-chuck 12 around the through hole 129, see [reference]. Figure 7 The sealing ring 126 also serves as the adhesive contact point and deformation-resistant support in the equipment. (See [link]). Figure 8A sealing ring 134 is provided on the third sub-chuck 13, which cooperates with the sealing ring 126. An assembly support 135 is provided around the outer periphery of the sealing ring 134. The sealing ring 126 includes an annular structure 1261 located at the center and a groove 1262 formed on the second sub-chuck 12 and concentric with the annular structure 1261. The sealing ring 134 is an annular structure protruding from the third sub-chuck 13 toward the second sub-chuck 12. In the assembled state, the sealing ring 134 is installed in the groove 1262, and the inner wall of the sealing ring 134 covers the outer wall of the annular structure 1261. The outer periphery of the sealing ring 134 is also covered by the assembly support 135. The height of the assembly support 135 is less than the height of the sealing ring 134, which can play a positioning and supporting role and can bear the resistance to deformation during assembly.

[0094] The second sub-chuck 12 fully utilizes the compartmentalized features of the first chamber 14 and the second chamber 15, such as... Figures 6-7 In this design, a support platform 114 is provided on the outer periphery of each second air nozzle 113, and a bonding hole 127 is provided at the corresponding position of each first air nozzle 112. By adding support structures at the spaced-apart positions of the second air nozzles 113 and first air nozzles 112, the overall deformation resistance of the main chuck 1 is enhanced. These support structures are preferably bonded supports. The uniformly distributed support structures help reduce stress deformation of the first sub-chuck 11, improve the flatness of the first sub-chuck 11, and increase measurement accuracy.

[0095] In another embodiment, the chuck assembly controls at least one of the gas pressure, flow rate, and flow rate at the first inlet and outlet via a first regulating unit. Specifically, the first regulating unit may be an air intake flow stabilizing device, and the first regulating unit is threadedly connected to the threaded hole 128 located on the second sub-chuck 12.

[0096] In this embodiment, a second regulating unit is also included to control at least one of the pressure, flow rate, and flow volume at the second inlet / outlet, thereby adjusting the characteristics of the air cushion between the main chuck 1 and the wafer. The control methods for both the first and second regulating units can be either control valves or computer software.

[0097] In another embodiment, the main chuck 1 is provided with a through hole 16 for mounting the sensor 17, and the through hole 16 is isolated from and connected to the first chamber 14 and the second chamber 15 by a sealing device. Figure 11 As shown, the sealing device includes a first inner sealing ring 122 located between the central through hole 16 and the first chamber 14, and a second inner sealing ring 132 located between the central through hole 16 and the second chamber 15.

[0098] The sensor 17 can be configured as a capacitive sensor to measure the position information corresponding to at least one position point on the wafer to be measured in order to obtain the reading of the sensor 17, or to monitor whether there is a wafer on the main chuck 1 based on the reading of the sensor 17, or to monitor the distance of the wafer from the main chuck 1 based on the reading of the sensor 17.

[0099] See Figure 9 The third sub-chuck 13 is provided with a third outer sealing ring 131 and a support seat 133 with adhesive support. The support seat 133 is coaxially distributed with the first air nozzle 112 in the axial direction. The third sub-chuck 13 and the second sub-chuck 12 define the second chamber 15.

[0100] In another embodiment, see Figure 10 As shown, the chuck assembly includes a support 2, and the main chuck 1 is detachably connected to the support 2. In this embodiment, the main chuck 1 adopts a modular design. By setting the main chuck 1 and the support 2 to be detachably connected, when it is necessary to replace the main chuck 1 with a different model or specification, it is not necessary to replace the support 2; only the main chuck 1 needs to be replaced directly. That is to say, the specifications and models of the main chuck 1 in the chuck assembly can be any number of different types, and these arbitrary number of main chuck 1 can be adapted to the same support 2. This method is efficient and quick to replace, which can improve measurement efficiency and save costs.

[0101] In another embodiment, the support 2 includes a fixed frame 21 and a movable frame 22 connected to the fixed frame 21. The support 2 also includes an adjustment mechanism 24 for adjusting the tilt angle of the movable frame 22. One end of the adjustment mechanism 24 is connected to the fixed frame 21 and the other end is connected to the movable frame 22.

[0102] With this setup, the main chuck 1 can be tilted at a certain angle in any direction. Through the effect of gravity after tilting, it can achieve automatic centering, which is efficient, fast, and has a high degree of repeatability.

[0103] The movable frame 22 is mounted on the fixed frame 21 via a spring 23 on the opposite side of the connection point between the fixed frame 21 and the movable frame 22. The support 2 further includes an adjustment mechanism 24 for adjusting the tilt angle of the movable frame 22, and the adjustment mechanism 24 is mounted on the fixed frame 21. In one embodiment of this application, the movable frame 22 is connected to the fixed frame 21 via a spring 23 on the opposite side of the connection point between the fixed frame 21 and the movable frame 22.

[0104] like Figure 10 As shown, in one embodiment, the adjustment mechanism 24 is configured to drive the movable frame 22 to move via a motor, the motor is fixed on the fixed frame 21, and the output shaft of the motor is connected to the movable frame 22.

[0105] In another embodiment, the movable frame 22 includes a first support plate 221 and a second support plate 222. The first support plate 221 is rotatably mounted on the side of the support plate 222 facing the main chuck 1, and the main chuck 1 is detachably mounted on the first support plate 221.

[0106] This application provides a measuring device according to another embodiment, which includes the chuck assembly described above.

[0107] In another embodiment, the measuring device includes an optical imaging component disposed on the side of the wafer away from the main chuck 1. The optical imaging component acquires an optical image of the side of the wafer away from the main chuck 1 to measure the shape and / or flatness of the wafer based on this optical image. When the specifications of the wafer to be measured change, the main chuck 1 of the corresponding size can be replaced.

[0108] The technical advantages of the measuring device are the same as those of the chuck assembly mentioned above, and will not be repeated here.

[0109] In this application, the main chuck is not limited to what is described in the specification and illustrations. Equivalent variations or modifications using similar nozzle distribution, support point distribution, cavity structure, and adhesive-enhanced stability features and principles should be included within the scope of this patent. Here, "wafer" can be a standard wafer or other test object.

[0110] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. Additionally, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects, but it can also represent an "and / or" relationship. Please refer to the context for a more accurate understanding.

[0111] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0112] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0113] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A chuck assembly, characterized in that, The chuck assembly includes a main chuck. The main chuck has support pillars for supporting the wafer and multiple air nozzles for forming an air cushion on its wafer-facing side. The support pillars form concentric support rings around the rotation center of the main chuck, and the air nozzles form concentric nozzle rings around the rotation center. At least one support ring is spaced between any two adjacent nozzle rings. The height of the support rings is adjustable. Each of the plurality of air nozzles can serve as both a pressure nozzle and a vacuum nozzle to form the air cushion to support the wafer; When the wafer is supported by suspension, if the air cushion strength between the wafer and the main chuck is insufficient to fully support the wafer, the wafer is supported on the support pillar to reduce local stress and deformation. When the main chuck supports the wafer by adsorption, the support pillar can flatten wafers with high spatial frequency or high warp to reduce the impact on wafer flatness.

2. The chuck assembly according to claim 1, characterized in that, The support columns located on the same support ring are evenly distributed circumferentially, and the distance between any two adjacent support rings is equal.

3. The chuck assembly according to claim 1, characterized in that, The distance ΔT between any two adjacent support columns in any circumferential direction and the distance ΔR between any two adjacent support rings are in a predetermined ratio.

4. The chuck assembly according to claim 3, characterized in that, The set ratio is set as follows: ΔT / ΔR = 2πn / N = 2π / m Where ΔT is the distance between two circumferentially adjacent support columns; ΔR is the distance between any two adjacent support rings; N is the number of support columns corresponding to each support ring; n is a natural number, referring to the sequence number of each support ring arranged from the inside out among multiple support rings; m refers to the number of support columns on the support ring with the smallest radius.

5. The chuck assembly according to claim 4, characterized in that, m is an even number.

6. The chuck assembly according to claim 5, characterized in that, m is 6.

7. The chuck assembly according to claim 4, characterized in that, ΔT and / or ΔR are not greater than 6 mm.

8. The chuck assembly according to claim 1, characterized in that, The plurality of support pillars are symmetrically distributed on the side of the main chuck facing the wafer.

9. The chuck assembly according to claim 1, characterized in that, The plurality of air nozzles are axially symmetrically distributed on the side of the chuck facing the wafer.

10. The chuck assembly according to claim 1, characterized in that, The air nozzle is configured as follows: ΔT' / ΔR'=2πn' / N'=2π / m', Where ΔT' is the distance between two circumferentially adjacent nozzles; ΔR' is the distance between any two adjacent nozzle rings; N' is the number of nozzles on each nozzle ring; n' is a natural number, referring to the sequence number of each nozzle ring arranged from the inside out among multiple nozzle rings; and m' refers to the number of nozzles on the nozzle ring with the smallest radius.

11. The chuck assembly according to claim 10, characterized in that, The difference between ΔT' and ΔR' is less than 8 mm.

12. The chuck assembly according to claim 1, characterized in that, The main chuck includes multiple sub-chucks, and the multiple sub-chucks include a first sub-chuck for supporting the wafer, with the support post located on the side of the first sub-chuck facing the wafer; The main chuck also includes a second sub-chuck fixed to the side of the first sub-chuck opposite to the wafer; It also includes a third sub-chuck fixed to the side of the second sub-chuck opposite to the wafer; The first sub-chuck and the second sub-chuck define a first chamber, the second sub-chuck and the third sub-chuck define a second chamber, and the air nozzle is disposed on the side of the first sub-chuck facing the wafer. The air nozzle includes a first air nozzle and a second air nozzle, wherein the first air nozzle communicates with the first chamber and the second air nozzle communicates with the second chamber.

13. The chuck assembly according to claim 12, characterized in that, Multiple sub-chucks are assembled to form a main chuck module.

14. The chuck assembly according to claim 12, characterized in that, The first chamber and the second chamber are independent of each other.

15. The chuck assembly according to claim 12, characterized in that, The first and second air nozzles are arranged alternately in the radial direction, or, on the same air nozzle ring, the first and second air nozzles are arranged alternately in the circumferential direction.

16. The chuck assembly according to claim 1, characterized in that, On the side of the main chuck facing the wafer, a first outer sealing ring is also provided, which is concentric with the support ring and located on the outer periphery of the main chuck. The top surface of the first outer sealing ring and the top surface of the support column are in the same plane, and the flatness is not greater than 8μm.

17. The chuck assembly according to claim 16, characterized in that, The first outer sealing ring is provided with an opening groove that radially penetrates the wall of the first outer sealing ring.

18. The chuck assembly according to claim 12, characterized in that, The main chuck is further provided with an annular support platform on the side facing the wafer, which is fitted around the outer periphery of at least three second air nozzles. The annular support platform is evenly distributed along the circumference of the rotation center.

19. The chuck assembly according to claim 12, characterized in that, The chuck assembly has: The first entrance / exit connects to the first chamber; The second entrance / exit connects to the second chamber; The first regulating unit is connected to the outlet of the first inlet / outlet, and controls at least one of the pressure, flow rate, and flow volume at the first inlet / outlet. The second regulating unit is connected to the second inlet and outlet, and controls at least one of the pressure, flow rate, and flow rate at the second inlet and outlet to regulate the characteristics of the air cushion.

20. The chuck assembly according to any one of claims 1-19, characterized in that, The chuck assembly includes a support, and the main chuck is detachably connected to the support.

21. The chuck assembly according to claim 20, characterized in that, The support includes a fixed frame and a movable frame connected to the fixed frame. The support also includes an adjustment mechanism for adjusting the tilt angle of the movable frame. One end of the adjustment mechanism is connected to the fixed frame, and the other end is connected to the movable frame.

22. The chuck assembly according to claim 21, characterized in that, The movable frame includes a first support plate and a second support. The first support plate is rotatably mounted on the side of the support plate facing the main chuck, and the main chuck is detachably mounted on the first support plate.

23. A measuring device, characterized in that, The measuring device includes a chuck assembly according to any one of claims 1-22.

24. The measuring device according to claim 23, characterized in that, The measuring device includes an optical imaging component disposed on the side of the wafer away from the main chuck.

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