Electrostatic adsorption device

Abstract

The utility model provides an electrostatic adsorption device which comprises a base body and an electrode layer, and the electrode layer is arranged on the upper surface of the base body. The electrode layer is used for electrostatic adsorption; the lower surface of the base body is provided with a first blind hole with a thin wall part between the bottom surface and the upper surface of the base body. The substrate is provided with the thin wall part between the first blind hole of the insert and the upper surface of the substrate, so that the fixed insert does not need to break through the upper surface of the substrate, an electrode can be arranged on the upper surface of the substrate through the electrode layer at the insert mounting position, and the realizable electrode area is increased; further, the electrostatic adsorption force and the distribution uniformity of the electrostatic adsorption force which can be realized by the electrostatic adsorption device are improved; meanwhile, the thickness of the thin-wall part ensures the mounting reliability of the electrode and the insert on the thin-wall part in the first blind hole; in addition, the connecting through hole in the corresponding position of the downward surface of the insert is a counter bore, so that the bottom surface of the fixing base can be kept flat when the insert is fixed, and the fixing reliability is high; and finally, the bottom surface of the fixed base is not influenced when the insert is fixed through the second threaded hole facing the side surface of the insert, and the operation is convenient.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor equipment, and in particular relates to an electrostatic adsorption device. Background Technology

[0002] In the semiconductor industry, especially in processes such as etching, chemical vapor deposition (CVD), physical vapor deposition (PVD), ion implantation, electron beam wafer inspection, and extreme ultraviolet lithography (EUVL), electrostatic chucks (ESCs) are commonly used to hold wafers in place by applying Coulomb forces or Johnsen-Rahbek forces (JRs) generated between the wafer and electrodes. Compared to traditional mechanical chucks, electrostatic chucks do not require large moving parts, have a lower risk of particle contamination, and offer higher reliability.

[0003] As semiconductor manufacturing processes continue to advance, the industry has increasingly stringent requirements for the wafer adsorption surface profile, including for electrostatic adsorption in vacuum environments. Improving the wafer adsorption surface profile means increasing the magnitude of the electrostatic adsorption force on the wafer and enhancing the uniformity of the electrostatic adsorption force distribution on the adsorption surface. This reduces wafer deformation caused by electrostatic adsorption and minimizes its impact on wafer yield.

[0004] Therefore, there is an urgent need for a structure that can improve the electrostatic adsorption surface of wafers.

[0005] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating the understanding of those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because these solutions have been described in the background section of this application. Utility Model Content

[0006] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide an electrostatic adsorption device to solve the problem of poor electrostatic adsorption surface shape of wafers in the prior art.

[0007] To achieve the above and other related objectives, this utility model provides the following technical solution:

[0008] This utility model provides an electrostatic adsorption device, which includes: a substrate and an electrode layer, wherein the electrode layer is located on the upper surface of the substrate;

[0009] The electrode layer includes a first electrode region and a second electrode region, the first electrode region and the second electrode region having opposite polarities, for electrostatic adsorption.

[0010] The lower surface of the substrate is provided with a first blind hole, and there is a thin-walled portion of a predetermined thickness between the bottom surface of the first blind hole and the upper surface of the substrate.

[0011] Optionally, the bulk resistivity of the matrix material is greater than or equal to 10. 14 Ω·cm.

[0012] Optionally, the preset thickness of the thin-walled portion is 0.5 mm to 5 mm.

[0013] Optionally, an insert is fixed inside the first blind hole, the insert including a first fixing structure.

[0014] Optionally, the first blind hole and the insert are fixedly connected by an adhesive.

[0015] Optionally, the adhesive is a vacuum adhesive.

[0016] Optionally, the insert is made of a non-magnetic material or a material with a relative permeability of less than or equal to 1.02.

[0017] Optionally, the electrostatic adsorption device further includes a fixed base located on the lower surface of the substrate; the fixed base is provided with a second fixing structure at the position of the insert of the first blind hole, and the second fixing structure is used to be detachably fixedly connected to the first fixing structure.

[0018] Optionally, the first fixing structure is a first threaded hole facing the lower surface of the insert; the fixing base is provided with a connecting through hole at the position of the insert corresponding to the first blind hole, the connecting through hole includes a first through hole with a first diameter and a second through hole with a second diameter, the second through hole is located below the first through hole, the first through hole and the second through hole are connected, the first diameter is smaller than the second diameter; the second fixing structure is a screw, the screw includes a screw rod and a head, the screw rod can pass through the first through hole from the bottom surface of the fixing base and be threadedly connected to the first threaded hole, the head can fall completely into the second through hole when the screw rod is threadedly connected to the first threaded hole.

[0019] Optionally, the first fixing structure is a second threaded hole on the side of the portion of the insert extending beyond the lower surface of the base; the fixing base has a second blind hole on its upper surface corresponding to the position of the insert, and the insert can be embedded in the second blind hole; when the insert is embedded in the second blind hole, a third through hole is provided on the side of the fixing base corresponding to the position of the second threaded hole; the second fixing structure is a screw, the screw including a shank and a head, the shank passing through the third through hole from the side of the fixing base and threadedly connected to the second threaded hole.

[0020] As described above, the electrostatic adsorption device of this invention has the following beneficial effects:

[0021] This invention establishes a thin-walled portion between the first blind hole on the lower surface of the substrate of the electrostatic adsorption device for setting the insert and the upper surface of the substrate. This eliminates the need to penetrate the upper surface of the substrate to set the insert, allowing electrodes to be set on the upper surface of the substrate even through the electrode layer at the insert installation location. This increases the electrode area that the electrostatic adsorption device can achieve, thereby increasing the electrostatic adsorption force that the electrostatic adsorption device can achieve and improving the uniformity of the distribution of the electrostatic adsorption force, which is beneficial to improving the reliability of electrostatic adsorption.

[0022] This invention, by setting the thickness of the thin-walled portion, allows electrodes to be placed above the thin-walled portion while ensuring the reliable installation of the insert within the first blind hole.

[0023] This utility model sets the connecting through hole at the corresponding position of the first threaded hole on the downward surface of the insert as a countersunk hole, so that when the insert is fixed to the fixed base, the bottom surface of the fixed base can remain flat, thus improving the fixing reliability.

[0024] This invention provides a second threaded hole facing the side of the insert, so that when the insert is fixed to the fixed base, the bottom surface of the fixed base does not need to be processed, making the operation convenient and quick. Attached Figure Description

[0025] Figure 1 The diagram shown is a top view of an electrostatic adsorption device in the prior art.

[0026] Figure 2 The diagram shown is a side cross-sectional view of the substrate of an electrostatic adsorption device in the prior art when no inserts are installed.

[0027] Figure 3 The diagram shows a side sectional view of an electrostatic adsorption device with an insert mounted on the substrate.

[0028] Figure 4 The diagram shown is a side sectional view of an electrostatic adsorption device in the prior art, where the substrate is fixedly connected to a fixed base via an insert.

[0029] Figure 5 The diagram shown is a top view of the electrostatic adsorption device in Embodiment 1 of this utility model.

[0030] Figure 6 The diagram shown is a side cross-sectional view of the substrate of the electrostatic adsorption device in Embodiment 1 of this utility model without the insert installed.

[0031] Figure 7 The diagram shown is a top view of an electrostatic adsorption device in an example of Embodiment 1 of this utility model.

[0032] Figure 8 The diagram shown is a top view of an electrostatic adsorption device in an example of Embodiment 1 of this utility model.

[0033] Figure 9 The image shown is a side sectional view of the substrate mounting insert of the electrostatic adsorption device in Embodiment 1 of this utility model.

[0034] Figure 10 The diagram shown is a side cross-sectional view of the electrostatic adsorption device in Embodiment 1 of this utility model, in which the substrate is fixedly connected to the fixed base via an insert.

[0035] Figure 11 The diagram shown is a top view of an electrostatic adsorption device in an example of Embodiment 1 of this utility model.

[0036] Figure 12 The diagram shown is a top view of an electrostatic adsorption device in the prior art.

[0037] Figure 13 The diagram shown is a partially enlarged side cross-sectional view of an example of Embodiment 1 of this utility model, showing the electrostatic adsorption device not mounted on a fixed base.

[0038] Figure 14 The diagram shown is a side cross-sectional view of the electrostatic adsorption device in Embodiment 2 of this utility model, in which the substrate is fixedly connected to the fixed base via an insert.

[0039] Component designation explanation

[0040] 11. Electrode layer; 111. First electrode region; 112. Central electrode portion; 113. First arc electrode; 114. First branch portion; 115. Second electrode region; 116. Edge electrode portion; 117. Second arc electrode; 118. Second branch portion; 12. Dielectric layer; 121. Radial; 122. First circumferential direction; 123. Second circumferential direction; 13. First electrode connection line; 14. Second electrode connection line; 15. Power supply; 16. First hole; 17. Second hole; 18. Fixing hole; 19. First countersunk hole;

[0041] 20. Substrate; 21. First blind hole; 22. Thin-walled portion; 23. Insert; 241. First threaded hole; 242. Second threaded hole;

[0042] 30. Fixed base; 310. Screw; 311. Threaded rod; 312. Head; 32. Connecting through hole; 321. First through hole; 322. Second through hole; 33. Second blind hole; 331. Third through hole;

[0043] 41. Wafer to be adsorbed; 42. Bump layer. Detailed Implementation

[0044] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.

[0045] In the detailed description of the embodiments of this utility model, for ease of explanation, the schematic diagrams illustrating the device structure may be partially enlarged without adhering to the general scale, and the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. Furthermore, in actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0046] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the accompanying drawings for devices in use or operation.

[0047] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0048] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0049] With the continuous development of semiconductor manufacturing processes, the industry has increasingly stringent requirements for the adsorption surface shape of wafers, and this is also true for electrostatic adsorption in a vacuum environment. The adsorption surface shape mainly includes the magnitude of the electrostatic adsorption force on the wafer and the uniformity of the distribution of the electrostatic adsorption force on the adsorption surface. It is an important indicator for measuring the reliability of wafer adsorption and is related to the product yield of wafers subjected to electrostatic adsorption.

[0050] In existing technologies, such as Figures 1-4 As shown, Figure 1 This is a top view of an existing electrostatic adsorption device. Figure 2 This is a side sectional view of the substrate 20 of the electrostatic adsorption device in the prior art when no inserts are installed. Figure 3A side sectional view of the substrate 20 of the electrostatic adsorption device in the prior art when the insert 23 is installed. Figure 4 This is a side cross-sectional view of the base 20 of the electrostatic adsorption device in the prior art, which is fixedly connected to the fixed base 30 by the insert 23. Since the base 20 of the electrostatic adsorption device often needs to be detachably fixed to the fixed base 30 below, it is often necessary to open through the upper and lower surfaces of the base 20 to obtain the first hole 16 on the base 20. The insert 23 is fixed in the first hole 16. Then, by setting a fixing hole 18 including a first countersunk hole 19 in the insert 23, the screw 310 can fall from the upper surface of the base 20 into the fixing hole 18, and is fixed through the fixing hole 18 to the fixed base 30 below the base 20 for threaded connection, thereby realizing the fixation of the base 20 on the fixed base 30. However, since the location of the first hole 16 on the upper surface of the substrate 20 requires opening through the upper surface of the substrate 20, the electrode layer 11 cannot be set at the location corresponding to the first hole 16 on the upper surface of the substrate 20. This not only reduces the electrode area that can be achieved on the surface of the substrate 20, but also prevents the upper surface of the substrate 20 at the location corresponding to the first hole 16 from generating an electrostatic adsorption force of the same strength as other locations. As a result, the overall electrostatic adsorption force on the surface of the substrate 20 is small and unevenly distributed, that is, the adsorption surface shape of the resulting electrostatic adsorption device is poor. This can easily lead to deformation of the surface of the wafer to be adsorbed on the surface of the electrostatic adsorption device or poor adsorption reliability, which is not conducive to the product yield after electrostatic adsorption.

[0051] Example 1:

[0052] This embodiment provides an electrostatic adsorption device, such as... Figures 5-6 As shown, Figure 5 This is a top view of the electrostatic adsorption device. Figure 6 This is a side cross-sectional view of the substrate 20 of the electrostatic adsorption device without any inserts; the electrostatic adsorption device includes: substrate 20 and electrode layer 11, the electrode layer 11 being located on the upper surface of the substrate 20.

[0053] The electrode layer 11 includes a first electrode region 111 and a second electrode region 115, the first electrode region 111 and the second electrode region 115 having opposite polarities, for electrostatic adsorption.

[0054] The lower surface of the substrate 20 is provided with a first blind hole 21, and there is a thin-walled portion 22 of a predetermined thickness between the bottom surface of the first blind hole 21 and the upper surface of the substrate 20.

[0055] This invention utilizes a substrate 20 of an electrostatic adsorption device with a lower surface for mounting such as... Figure 9There is a thin-walled portion 22 of preset thickness between the first blind hole 21 of the insert 23 and the upper surface of the substrate 20, so that the position of the insert 23 on the substrate 20 does not need to be opened through the upper surface of the substrate 20. Electrodes can still be set on the upper surface of the substrate 20 through the electrode layer 11 at the installation position of the insert 23. Compared with the prior art, the electrode area that the electrostatic adsorption device can achieve is increased, thereby increasing the electrostatic adsorption force that the electrostatic adsorption device can achieve, and improving the uniformity of the distribution of the electrostatic adsorption force of the electrostatic adsorption device. The adsorption surface shape of the electrostatic adsorption is greatly optimized, which is conducive to the reliability of electrostatic adsorption and the improvement of the yield of wafer products after electrostatic adsorption.

[0056] In one embodiment, such as Figure 7-Figure 8 The image shows a top view of two electrostatic adsorption devices, with the cross-section of the dielectric layer 12 at a preset height being a circular plane.

[0057] The first electrode region 111 includes a central electrode portion 112, m first branch portions 114, and m groups of first arc portions. Each group of first arc portions includes n first arc electrodes 113. The central electrode portion 112 is a first arc shape that coincides with the center of the circular plane. The first branch portions 114 extend along the radial direction 121 of the circular plane. All m first branch portions 114 are connected to the outer periphery of the central electrode portion 112. Each group of first arc portions and first branch portions 114 are connected in pairs. The n first arc electrodes 113 in the same group of first arc portions are arcs corresponding to the same central angle of n concentric circles with different radii and larger than the first arc shape.

[0058] The second electrode region 115 includes an edge electrode portion 116, m second branch portions 118, and m groups of second arc portions. Each group of second arc portions includes n second arc electrodes 117. The edge electrode portion 116 is a second arc shape that coincides with the center of the circular plane. The second branch portions 118 extend along the radial direction 121 of the circular plane. All m second branch portions 118 are connected to the inner periphery of the edge electrode portion 116. Each group of second arc portions and second branch portions 118 are connected in pairs. The n second arc electrodes 117 in the same group of second arc portions are arcs corresponding to the same central angle of n concentric circles with different radii and smaller than the second arc shape.

[0059] m is an integer greater than or equal to 1, and n is an integer greater than 2; the first electrode region 111 and the second electrode region 115 have opposite polarities; the first arc electrode 113 and the second arc electrode 117 adjacent to each other along the radial direction 121 of the circular plane are interdigitated and staggered, and the dielectric layer 12 covers the exposed surfaces of the first arc electrode 113 and the second arc electrode 117 and fills the gaps between their surfaces; the radius of the central electrode portion 112 is smaller than the radius of any second arc electrode 117, and the radius of the edge electrode portion 116 is larger than the radius of any first arc electrode 113.

[0060] In one embodiment, such as Figure 7 As shown, each group of first arc portions is distributed on the same side of its corresponding connected first branch portion 114 along the first circumferential direction 122 of the circular plane; each group of second arc portions is distributed on the same side of its corresponding connected second branch portion 118 along the second circumferential direction 123 of the circular plane; one of the first circumferential direction 122 and the second circumferential direction 123 is clockwise, and the other is counterclockwise. Figure 7 As shown, the first circumferential direction 122 is counterclockwise, and the second circumferential direction 123 is clockwise. In other embodiments, the first circumferential direction 122 may be clockwise, and the second circumferential direction 123 may be counterclockwise.

[0061] Specifically, in this embodiment, as Figure 7 As shown, the interior of the central electrode portion 112 is filled with a dielectric layer 12.

[0062] In one embodiment, such as Figure 8 As shown, each group of first arc portions is distributed on one side of its corresponding connected first branch 114 along the first circumferential direction 122 of the circular plane and on one side along the second circumferential direction 123 of the circular plane; each group of second arc portions is distributed on one side of its corresponding connected second branch 118 along the first circumferential direction 122 of the circular plane and on one side along the second circumferential direction 123 of the circular plane; one of the first circumferential direction 122 and the second circumferential direction 123 is clockwise and the other is counterclockwise.

[0063] This invention improves the density of arc-shaped electrodes that the electrostatic adsorption device can accommodate by setting the distribution of the first electrode region 111 and the second electrode region 115, and in conjunction with... Figure 9 The first blind hole 21 shown eliminates the electrode area that needs to penetrate the substrate 20 to install the insert 23, greatly improving the electrostatic adsorption force that the electrostatic adsorption device can achieve.

[0064] In one embodiment, such as Figure 5 As shown, the first electrode region 111 includes a central electrode portion 112, a first branch portion 114, and a set of first arc portions. The first arc electrode 113 of each set of first arc portions is distributed on one side of the corresponding connected first branch portion 114 along the first circumferential direction 122 of the circular plane and on one side along the second circumferential direction 123 of the circular plane. The second electrode region 115 includes an edge electrode portion 116, a second branch portion 118, and a set of second arc portions. The second arc electrode 117 of each set of second arc portions is distributed on one side of the corresponding connected second branch portion 118 along the first circumferential direction 122 of the circular plane and on one side along the second circumferential direction 123 of the circular plane.

[0065] Specifically, the first electrode region 111 and the second electrode region 115 within the electrode layer 11 can be arranged in any other suitable manner, all of which are within the protection scope of this utility model.

[0066] In one embodiment, such as Figure 5 As shown, the dielectric layer 12 fills the gap between any adjacent portions of the first electrode region 111 and the second electrode region 115 to ensure that the first electrode region 111 is not short-circuited with the second electrode region 115, and at the same time protects the electrode from oxidation or damage.

[0067] In one embodiment, such as Figure 6 The bulk resistivity of the substrate 20 described herein is greater than or equal to 10. 14 Ω·cm.

[0068] This invention reduces the leakage current of the electrostatic adsorption device by setting the substrate 20 to have high volume resistivity, thereby extending the adsorption retention time of the electrostatic adsorption device and improving the adsorption reliability of the electrostatic adsorption device.

[0069] In one embodiment, such as Figure 6 The preset thickness of the thin-walled portion 22 is 0.5 mm to 5 mm.

[0070] This invention, by setting the thickness range of the thin-walled portion 22, ensures that the preset thickness of the thin-walled portion 22 is sufficiently thick to provide adequate support for the electrode layer 11 disposed above the thin-walled portion 22; simultaneously, it ensures that the preset thickness of the thin-walled portion 22 is sufficiently thin to guarantee... Figure 9 The insert 23 has sufficient installation depth within the first blind hole 21, which improves the fixation reliability of the insert 23 within the first blind hole 21 and ensures the fixation reliability between the base 20 and the fixed base 30.

[0071] In one embodiment, such as Figure 9 The figure shows a side cross-sectional view of the substrate 20 of the electrostatic adsorption device with the insert 23 installed. The insert 23 is fixed in the first blind hole 21 and the insert 23 includes a first fixing structure.

[0072] In one embodiment, the first blind hole 21 and the insert 23 are fixedly connected by an adhesive.

[0073] In one embodiment, the adhesive is a vacuum adhesive.

[0074] Specifically, when the wafer to be adsorbed is adsorbed by the electrostatic adsorption device and used in a vacuum environment chamber, the insert 23 is fixed in the first blind hole 21 using a vacuum adhesive, thereby improving the sealing performance of the insert 23 in the vacuum environment and improving the fixing reliability of the insert 23.

[0075] In one embodiment, the insert 23 is made of a non-magnetic material or a material with a relative permeability of less than or equal to 1.02.

[0076] Preferably, when the wafer to be adsorbed by the electrostatic adsorption device needs to undergo electron beam-related processing operations, the aforementioned non-magnetic or low-magnetic material is used as the material of the insert 23.

[0077] This invention avoids the electrostatic adsorption device affecting the accuracy of the electron beam when the insert 23 is made of a non-magnetic or low-magnetic material.

[0078] In one embodiment, such as Figure 10 The figure shown is a side cross-sectional view of the base 20 of the electrostatic adsorption device when it is fixedly connected to the fixed base 30 through the insert 23. The electrostatic adsorption device also includes the fixed base 30, which is located on the lower surface of the base 20. The fixed base 30 is provided with a second fixing structure at the position of the insert 23 of the first blind hole 21. The second fixing structure is used to be detachably fixedly connected to the first fixing structure.

[0079] In this embodiment, as Figure 10 As shown, the first fixing structure is the first threaded hole 241 of the insert 23 facing the lower surface; the fixing base 30 is provided with a connecting through hole 32 at the position of the insert 23 corresponding to the first blind hole 21. The connecting through hole 32 includes a first through hole 321 with a first diameter and a second through hole 322 with a second diameter. The second through hole 322 is located below the first through hole 321. The first through hole 321 and the second through hole 322 are connected. The first diameter is smaller than the second diameter. The second fixing structure is a screw 310. The screw 310 includes a screw 311 and a head 312. The screw 311 can pass through the first through hole 321 from the bottom surface of the fixing base 30 and be threaded to the first threaded hole 241. The head 312 can fall completely into the second through hole 322 when the screw 311 is threaded to the first threaded hole 241.

[0080] This utility model sets the first fixing structure so that the connecting through hole 32 at the position corresponding to the first threaded hole 241 on the lower surface of the insert 23 is a first through hole 321 with a diameter larger than the second through hole 322, which is a countersunk hole. When the insert 23 is fixed to the fixing base 30 through the second fixing structure, the second fixing structure on the bottom surface of the fixing base 30 will not protrude from the lower surface, so that the bottom surface of the fixing base 30 can remain flat and improve the fixing reliability.

[0081] Specifically, the first fixing structure and the second fixing structure can also adopt other suitable detachable connection structures to achieve the fixed connection between the insert 23 and the fixed base 30, all of which are within the protection scope of this utility model.

[0082] In one embodiment, such as Figure 11 The image shown is a top view of an electrostatic adsorption device including a second hole 17. The electrostatic adsorption device further includes a second hole 17, which extends through... Figure 6 The upper and lower surfaces of the matrix 20.

[0083] Specifically, the second hole 17 provides space for the extension and retraction of the pin in the process chamber of the electrostatic adsorption device; generally, the diameter of the second hole 17 is smaller than that of... Figure 1 The aperture required for the first hole 16 for mounting the insert 23 in the prior art is different due to the use of the present application. Figure 9 The solution uses a first blind hole 21 to eliminate the need for a larger electrode area for mounting the insert 23. Therefore, even in some applications where a blind hole is required, the electrode area can be reduced. Figure 11 The second hole 17 in the electrostatic adsorption device will also achieve, for example... Figure 12 The prior art shown has a better adsorption surface shape for electrostatic adsorption devices that simultaneously include the first hole 16 and the second hole 17.

[0084] Specifically, such as Figure 13 The image shown is a partially enlarged side sectional view of the electrostatic adsorption device not mounted on the fixed base. Details not shown include... Figure 6 The substrate 20 is provided with a first blind hole 21 and an insert 23; the electrode connection point of the first electrode region 111 is electrically connected to one end of the first electrode connection line 13, the electrode connection point of the second electrode region 115 is electrically connected to one end of the second electrode connection line 14, and the other end of the first electrode connection line 13 (the end not connected to the first electrode region 111) and the other end of the second electrode connection line 14 (the end not connected to the second electrode region 115) are respectively connected to the two electrodes of the power supply 15, thereby supplying power to the first electrode region 111 and the second electrode region 115.

[0085] Specifically, both the first electrode connecting wire and the second electrode connecting wire need to pass through the substrate 20 to achieve electrical connection with the power source. However, the aperture of the holes required for the first electrode connecting wire and the second electrode connecting wire to pass through the substrate 20 is extremely small, similar to... Figure 6 Compared to the first blind hole 21, it can be ignored; at the same time, since the first electrode connecting line and the second electrode connecting line are used to realize the electrical connection of the electrode layer 11, their passage through the hole of the substrate 20 does not affect the electrode area of ​​the electrode layer 11 and the uniformity of the distribution of electrostatic adsorption force, and therefore does not affect the adsorption surface shape of electrostatic adsorption.

[0086] In one embodiment, the first electrode connection line 13 and such Figure 11 The first branch 114 is fixedly connected to each other by processes such as brazing and bonding with conductive adhesive; the second electrode connecting wire 14 is connected to... Figure 11 The second branch 118 is fixedly connected by processes such as brazing and bonding with conductive adhesive.

[0087] In one embodiment, such as Figure 13 As shown, the first electrode region 111 is electrically connected to the positive terminal of the power supply 15, and the second electrode region 115 is electrically connected to the negative terminal of the power supply 15.

[0088] In one embodiment, the first electrode region 111 is electrically connected to the negative terminal of the power supply 15, and the second electrode region 115 is electrically connected to the positive terminal of the power supply 15.

[0089] In one embodiment, such as Figure 13 As shown, the dielectric layer 12 covers all exposed surfaces of each part of the first electrode region 111 and the second electrode region 115 and fills the gaps between any adjacent parts of the first electrode region 111 and the second electrode region 115, so as to ensure that the first electrode region 111 is not short-circuited with the second electrode region 115, and at the same time protect the electrode from oxidation or damage.

[0090] In one embodiment, such as Figure 13 As shown, the dielectric layer 12 that fills the gap between the first electrode region 111 and the second electrode region 115 is also located on the upper surface of the substrate 20.

[0091] In one embodiment, such as Figure 13 As shown, a bump layer 42 may also be provided between the medium layer 12 and the protective layer (not shown in the figure) of the electrostatic adsorption device, and the protective layer covers the exposed surface of the bump layer 42.

[0092] In one embodiment, the material of the bump layer 42 is the same as the material of the dielectric layer 12.

[0093] In one embodiment, the bump layer 42 can be formed on the dielectric layer 12 by processes such as exposure etching and sandblasting.

[0094] In one embodiment, the protective layer can be bonded to the bump layer 42 by processes such as vapor deposition or magnetron sputtering.

[0095] Specifically, the electrostatic adsorption device with bump layer 42 increases the particle-accommodating space between the wafer 41 to be adsorbed and the electrostatic adsorption device by the presence of bumps. This reduces the risk of particles directly getting stuck on the contact surface between the wafer 41 to be adsorbed and the electrostatic adsorption device, causing damage to the surface of the wafer 41 to be adsorbed, and improves the yield of the wafer 41 to be adsorbed after adsorption by the electrostatic adsorption device. However, at the same time, the presence of bump layer 42 will reduce the polarization electric field between the wafer 41 to be adsorbed and the electrostatic adsorption device, thereby reducing the adsorption force of the electrostatic adsorption device on the wafer 41 to be adsorbed. Those skilled in the art can choose whether to provide bump layer 42 according to the requirements of surface quality and adsorption force of the wafer 41 to be adsorbed in actual applications. In this embodiment, it is mainly used to provide stronger adsorption force for the wafer 41 to be adsorbed with high resistivity, so it is preferable not to provide bump layer 42.

[0096] Preferably, the bulk resistivity of the dielectric layer 12 is greater than or equal to 10. 14 Ω·cm.

[0097] By using a dielectric layer 12 with high volume resistivity, this invention can reduce the leakage current of the electrostatic adsorption device, thereby extending the adsorption and holding time of the wafer 41 to be adsorbed and improving the adsorption reliability of the electrostatic adsorption device.

[0098] In one embodiment, the thickness of the dielectric layer 12 is 10 micrometers to 1 millimeter.

[0099] This invention ensures a stronger gradient force by setting the thickness range of the dielectric layer 12, thereby achieving a better adsorption effect on the wafer 41 to be adsorbed.

[0100] Preferably, the dielectric layer 12 has a high melting point.

[0101] In one embodiment, the dielectric layer 12 is made of alumina, AlN, polyimide, or other materials with high melting point and high volume resistivity.

[0102] In one embodiment, the bulk resistivity of the wafer 41 to be adsorbed is greater than or equal to 10. 13 Ω·cm. Specifically, the bulk resistivity of the wafer 41 to be adsorbed can also be a smaller value, but the adsorption effect of the present invention on the high resistivity wafer 41 that requires stronger adsorption force is better demonstrated when the bulk resistivity of the wafer 41 to be adsorbed is higher.

[0103] In one embodiment, the wafer 41 to be adsorbed is sapphire, glass substrate, ceramic substrate, etc., or other suitable materials.

[0104] In one embodiment, the first electrode region 111 and the second electrode region 115 can be connected to the substrate 20 at the bottom by means of spraying, vapor deposition or printing, and then the first electrode region 111 and the second electrode region 115 can be tightly bonded to the substrate 20 by high-temperature sintering.

[0105] In one embodiment, the dielectric layer 12 can be tightly bonded to the substrate 20 at the bottom through processes such as printing, casting, or high-temperature co-firing.

[0106] In one embodiment, after the basic structure of the electrostatic adsorption device is prepared, the final electrostatic adsorption device is manufactured by grinding, polishing and cleaning.

[0107] Example 2:

[0108] This embodiment provides an electrostatic adsorption device. Other features of the electrostatic adsorption device are basically the same as those in Embodiment 1, except that:

[0109] In this embodiment, as Figure 14 The diagram shows a side cross-sectional view of the electrostatic adsorption device, where the base 20 is fixedly connected to the fixed base 30 via an insert 23. The first fixing structure is a second threaded hole 242 extending from the lower surface of the insert 23 towards the side. The fixed base 30 has a second blind hole 33 on its upper surface corresponding to the position of the insert 23, and the insert 23 can be inserted into the second blind hole 33. When the insert 23 is inserted into the second blind hole 33, a third through hole 331 is provided on the side of the fixed base 30 corresponding to the position of the second threaded hole 242. The second fixing structure is a screw 310, which includes a screw 311 and a head 312. The screw 311 can pass through the third through hole 331 from the side of the fixed base 30 and be threadedly connected to the second threaded hole 242.

[0110] This utility model sets the first fixing structure as the second threaded hole 242 facing the side of the insert 23. When the insert 23 is fixed to the fixing base 30 through the first fixing structure, the bottom surface of the fixing base 30 does not need to be processed. It is only necessary to connect and fix the first fixing structure and the second fixing structure from the side of the fixing base 30. The operation is convenient and quick, which helps to improve the fixing efficiency of the base 20.

[0111] In summary, the electrostatic adsorption device of this invention, by setting a thin-walled portion between the first blind hole on the lower surface of the substrate for mounting the insert and the upper surface of the substrate, eliminates the need to penetrate the upper surface of the substrate to position the insert. This allows electrodes to be mounted on the upper surface of the substrate even through the electrode layer at the insert mounting position, thereby increasing the achievable electrode area, which in turn increases the achievable electrostatic adsorption force and improves the uniformity of the electrostatic adsorption force distribution, thus enhancing the reliability of electrostatic adsorption. Furthermore, by setting the thickness of the thin-walled portion, electrodes can be mounted above it while ensuring the reliable installation of the insert within the first blind hole. Additionally, by setting the connecting through hole corresponding to the first threaded hole on the lower surface of the insert as a countersunk hole, the bottom surface of the fixing base remains flat when the insert is fixed to the base, improving the reliability of the fixing. Finally, by setting a second threaded hole on the side of the insert, the bottom surface of the fixing base does not require machining when the insert is fixed to the base, making operation convenient and quick.

[0112] Therefore, this utility model effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0113] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. An electrostatic adsorption device, characterized in that, The electrostatic adsorption device includes a substrate (20) and an electrode layer (11), wherein the electrode layer (11) is located on the upper surface of the substrate (20); The electrode layer (11) includes a first electrode region (111) and a second electrode region (115), the first electrode region (111) and the second electrode region (115) having opposite polarities, for electrostatic adsorption; The lower surface of the substrate (20) is provided with a first blind hole (21), and there is a thin-walled portion (22) of a predetermined thickness between the bottom surface of the first blind hole (21) and the upper surface of the substrate (20).

2. The electrostatic adsorption device according to claim 1, characterized in that: The material resistivity of the matrix (20) is greater than or equal to 10. 14 Ω·cm.

3. The electrostatic adsorption device according to claim 1, characterized in that: The preset thickness of the thin-walled portion (22) is 0.5 mm to 5 mm.

4. The electrostatic adsorption device according to claim 1, characterized in that: An insert (23) is fixed inside the first blind hole (21), and the insert (23) includes a first fixing structure.

5. The electrostatic adsorption device according to claim 4, characterized in that: The first blind hole (21) and the insert (23) are fixedly connected by adhesive.

6. The electrostatic adsorption device according to claim 5, characterized in that: The adhesive is a vacuum adhesive.

7. The electrostatic adsorption device according to claim 4, characterized in that: The insert (23) is made of a non-magnetic material or a material with a relative permeability of less than or equal to 1.

02.

8. The electrostatic adsorption device according to any one of claims 4-7, characterized in that: The electrostatic adsorption device further includes a fixed base (30), which is located on the lower surface of the substrate (20); the fixed base (30) is provided with a second fixing structure at the position of the insert (23) of the first blind hole (21), and the second fixing structure is used to be detachably fixedly connected to the first fixing structure.

9. The electrostatic adsorption device according to claim 8, characterized in that: The first fixing structure is the first threaded hole (241) of the insert (23) facing the lower surface; the fixing base (30) is provided with a connecting through hole (32) at the position of the insert (23) corresponding to the first blind hole (21). The connecting through hole (32) includes a first through hole (321) with a first diameter and a second through hole (322) with a second diameter. The second through hole (322) is located below the first through hole (321). The first through hole (321) and the second through hole (322) are connected. The first hole diameter is smaller than the second hole diameter; the second fixing structure is a screw (310), the screw (310) includes a screw rod (311) and a head (312), the screw rod (311) can pass through the bottom surface of the fixing base (30) through the first through hole (321) and be threaded to the first threaded hole (241), and the head (312) can fall completely into the second through hole (322) when the screw rod (311) is threaded to the first threaded hole (241).

10. The electrostatic adsorption device according to claim 8, characterized in that: The first fixing structure is a second threaded hole (242) on the side of the part of the insert (23) that extends beyond the lower surface of the base (20); the fixing base (30) is provided with a second blind hole (33) on the upper surface corresponding to the position of the insert (23), and the insert (23) can be inserted into the second blind hole (33); when the insert (23) is inserted into the second blind hole (33), the side of the fixing base (30) is provided with a third through hole (331) corresponding to the position of the second threaded hole (242); the second fixing structure is a screw (310), the screw (310) includes a screw rod (311) and a head (312), and the screw rod (311) can pass through the third through hole (331) from the side of the fixing base (30) and be threadedly connected to the second threaded hole (242).

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