Electrostatic chuck and method of manufacturing the same

Abstract

The application relates to the technical field of semiconductor devices, and provides an electrostatic chuck and a manufacturing method thereof, the electrostatic chuck comprising a ceramic disc, a base and a connecting layer located between the ceramic disc and the base; wherein the connecting layer comprises a bonding layer and a filling layer, the bonding layer and the filling layer are arranged in the same layer, the bonding layer comprises a plurality of bonding sublayers arranged at intervals, and the filling layer fills the gaps between the bonding sublayers. According to the application, the connecting layer is designed as the bonding sublayers and the filling layer arranged in the same layer and alternately arranged, the stress field can be effectively divided, the bonding sublayers and the filling layer are alternately arranged, the extrusion on the ceramic disc caused by the expansion of the bonding sublayers can be reduced, the risk of peeling and cracking between the connecting layer and the base and the ceramic disc is significantly reduced, and the service life of the electrostatic chuck is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor devices, and in particular to an electrostatic chuck and a manufacturing method thereof. BACKGROUND

[0002] In the process of continuous progress of semiconductor manufacturing technology, semiconductor devices such as dynamic access random memory (DRAM) and 3D NAND structure need to build deep hole structures inside to meet the increasingly complex functional requirements. For example, in DRAM manufacturing, capacitors can be formed by etching a single stack of silicon dioxide (SiO2). As the semiconductor process continues to develop towards higher integration and smaller size, the aspect ratio (HAR) of the etched features increases dramatically, exceeding 50:1, bringing many severe challenges to the etching process.

[0003] Currently, 3D NAND chip technology has made a major breakthrough, and has reached a new height of 1000 layers. Under this development background, low-temperature etching technology stands out with its unique advantages. In a low-temperature environment (such as -70℃), low-temperature etching technology can achieve high-speed etching, with an etching rate of more than twice that of traditional technology, and also ensures high precision of etching. Therefore, low-temperature etching equipment has been widely used in the field of semiconductor manufacturing. The electrostatic chuck used in the etching equipment is a key component for supporting the wafer, which is mainly composed of a ceramic disc, a base, and a bonding layer between the ceramic disc and the base. However, the special working conditions of low-temperature etching put new and higher requirements on the performance of the electrostatic chuck, and the performance of the traditional electrostatic chuck has been difficult to adapt to this low-temperature etching environment.

[0004] In order to improve the performance of the electrostatic chuck in the low-temperature etching environment, a series of researches have been carried out in the industry and some achievements have been made: for example, by increasing the content of filler in the bonding layer to improve the thermal conductivity of the bonding layer, when the content of the filler is controlled at 70% or below, the bonding layer can still maintain a high critical shear strain (flexibility) under low temperature conditions (-80℃ to -60℃), effectively reducing the risk of peeling. However, the resin material used in the bonding layer in this study has a relatively low thermal conductivity, which to some extent affects the temperature rise rate and uniformity.

[0005] For another example, an existing electrostatic chuck structure uses ceramic material for the electrostatic adsorption layer, and the base is composed of two metal layers, the first metal layer close to the electrostatic adsorption layer and the second metal layer below it. However, the two metal layers are mainly made of refractory metal, and this structure has the problem of difficulty in bonding the metal layer with the ceramic disc, resulting in a low yield of the product.

[0006] For another example, there is also a low-temperature electrostatic chuck in the prior art, whose ceramic disc material is alumina (Al2O3). ) is mainly composed of silicon carbide (SiC) and is compounded with silicon carbide (SiC) to improve the plasma resistance. The base is mainly composed of silicon carbide (SiC), and the bonding layer adopts a single layer or a multi-layer (such as a stress release layer + double bonding layer) structure, and the double bonding layer selects a low-melting-point alloy (such as Ag-Cu-Ti alloy) and an active metal (Ti, Zr, Hf) to enhance the interface bonding with the ceramic disc. Although the stress release layer reduces the interface stress to a certain extent, the bonding strength still needs to be improved, and it is difficult to bond a large area in a high-temperature environment, and cracking is prone to occur after repeated use.

[0007] When the etching temperature is lower than-60℃, the toughness of the traditional connecting material is significantly reduced under low-temperature conditions, and brittle fracture is prone to occur. Although the multi-layer metal connection method improves the low-temperature brittleness to a certain extent, due to the difference between the thermal expansion coefficients of the metal and the ceramic, and the large-area connection between the metal layer and the ceramic disc, a large deformation is prone to occur during the service of the electrostatic chuck, and even cracking occurs, thereby causing the electrostatic chuck to fail prematurely.

[0008] Therefore, it is of great practical significance to develop a stable and reliable electrostatic chuck bonding layer structure suitable for low-temperature etching environment, which can improve the quality and efficiency of semiconductor manufacturing and promote the further development of semiconductor technology. SUMMARY

[0009] The present application provides an electrostatic chuck and a manufacturing method thereof, which solves the problem that the metal bonding layer of the existing electrostatic chuck and the ceramic disc are connected in a large area, and the electrostatic chuck is prone to deformation and cracking, resulting in premature failure of the electrostatic chuck.

[0010] The present application provides an electrostatic chuck, comprising a ceramic disc, a base and a connecting layer between the ceramic disc and the base.

[0011] The connecting layer comprises a bonding layer and a filling layer, and the bonding layer and the filling layer are arranged in the same layer. The bonding layer comprises a plurality of bonding sublayers arranged at intervals, and the filling layer fills the gaps between the bonding sublayers.

[0012] Optionally, the bonding layer is a metal material.

[0013] Optionally, the material of the bonding layer is selected from at least one of Al, AlSi, AlSiCu, AlSiMg and AlMgSiFe.

[0014] Optionally, the melting point of the bonding layer is lower than the melting point of the filling layer.

[0015] Optionally, the filling layer deforms under a preset pressure, and the compression range of the filling layer is 5%-30%.

[0016] Optionally, the orthographic projection of the bonding layer on the base does not overlap with the orthographic projection of the filling layer on the base.

[0017] Alternatively, the orthographic projection of the bonding layer on the base partially overlaps with the orthographic projection of the filling layer on the base, and the overlapping area ranges from 0.5% to 10%.

[0018] Optionally, the thickness of the bonding layer ranges from 0.05 mm to 0.2 mm, and the thickness of the filling layer ranges from 0.065 mm to 0.25 mm.

[0019] Optionally, the material of the filling layer is selected from at least one of Cu, Ag, Au, and Pt, or the material of the filling layer is selected from at least one of graphite paper, carbon fiber, graphene, and copper-coated graphene, or the material of the filling layer is ceramic glue.

[0020] Optionally, the bonding sub-layer is in a ring, block, or strip structure.

[0021] The application also provides a manufacturing method of the electrostatic chuck as described in any one of the above, comprising the following steps:

[0022] Step 1: obtaining a ceramic disc with embedded electrodes by using a high-temperature co-firing process;

[0023] Step 2: forming a base by using a hot-press sintering and welding process;

[0024] Step 3: placing a plurality of filling layers on the upper surface of the base in an interval manner, and placing a bonding layer in the gap between two adjacent filling layers, so that the filling layers and the bonding layer cover the upper surface of the base to form a connecting layer;

[0025] Step 4: placing the ceramic disc on the upper surface of the connecting layer, and assembling the base, the connecting layer, and the ceramic disc;

[0026] Step 5: placing the assembled base, connecting layer, and ceramic disc into a vacuum brazing device for vacuum brazing, the bonding layer is melted after being heated to tightly connect the base and the ceramic disc, and the filling layer is compressed and deformed under the preset pressure of the vacuum brazing device and tightly adheres to the base and the ceramic disc.

[0027] The above technical solution of the application has the following beneficial effects:

[0028] The electrostatic chuck and the manufacturing method thereof, by designing the connecting layer between the base and the ceramic disc as a combination layer and a filling layer arranged in the same layer, wherein the combination layer comprises a plurality of combination sub-layers arranged at intervals, and the filling layer fills the gap between each combination sub-layer, the combination sub-layers and the filling layers arranged in the same layer and alternately arranged can effectively divide the stress field, and each block of combination sub-layers can independently expand and contract, thereby greatly reducing the overall constraint force; the alternately arranged combination sub-layers and filling layers can reduce the extrusion on the ceramic disc when the combination sub-layers expand, thereby greatly reducing the risk of peeling and cracking between the connecting layer and the base and the ceramic disc, and prolonging the service life of the electrostatic chuck. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0030] Figure 1 The cross-sectional view of the electrostatic chuck provided by the embodiments of the present application;

[0031] Figure 2 The planar distribution diagram of the connecting layer of the electrostatic chuck provided by the embodiments of the present application;

[0032] Figure 3 The manufacturing method flow chart of the electrostatic chuck provided by the embodiments of the present application.

[0033] Reference signs:

[0034] 100, ceramic disc; 110, base; 120, connecting layer; 105, electrostatic electrode; 106, heating electrode; 121, combination layer; 122, filling layer; 130, air hole; 135, Pin hole; 1211, combination sub-layer. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present application more clear, the technical solutions in the present application will be described clearly and completely below in combination with the drawings in the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0036] Metal and ceramic materials have different expansion / shrinkage amounts, and a large shear stress is generated at the interface. When a large-area metal layer is rigidly connected with a ceramic disc, the expansion deformation of the metal is inhibited by the ceramic, and the stress is concentrated at the connection boundary. As a brittle material, the ceramic has low tensile strength and is prone to crack initiation and propagation in the stress concentration area.

[0037] Based on this, the present application provides an electrostatic chuck aiming to reduce the risk of cracking of the electrostatic chuck and prolong its service life. Please refer to Figure 1 and Figure 2 The electrostatic chuck comprises a ceramic disc 100, a base 110, and a connecting layer 120 between the ceramic disc 100 and the base 110. The connecting layer 120 comprises a bonding layer 121 and a filling layer 122, and the bonding layer 121 and the filling layer 122 are arranged in the same layer. The bonding layer 121 comprises a plurality of bonding sub-layers 1211 arranged in the horizontal direction and spaced apart from each other, and the filling layer 122 fills the gaps between the bonding sub-layers 1211.

[0038] The present application can effectively divide the stress field by designing the connecting layer 120 as the bonding sub-layers 1211 and the filling layer 122 arranged in the same layer and alternately arranged. The bonding sub-layers 1211 of each block can independently expand and contract with heat, greatly reducing the overall constraint. In addition, the alternate arrangement of the bonding sub-layers 1211 and the filling layer 122 can reduce the extrusion on the ceramic disc 100 when the bonding sub-layers 1211 expand, greatly reducing the risk of peeling and cracking between the connecting layer 120 and the base 110 and the ceramic disc 100. Even if the interface of the area corresponding to a certain bonding sub-layer 1211 cracks, the crack will be blocked by the filling layer 122 between the adjacent two bonding sub-layers 1211, avoiding the crack penetrating through the entire connecting layer 120, and prolonging the service life of the electrostatic chuck.

[0039] The ceramic disc 100 is internally embedded with a plurality of electrostatic electrodes 105 and a plurality of heating electrodes 106. Since the connecting layer 120 comprises the bonding sub-layers 1211 and the filling layer 122 arranged in the same layer and alternately arranged, it can allow the heating electrodes 106 to achieve more precise local temperature control, improve temperature uniformity, and avoid warping caused by uneven temperature when the traditional metal bonding layer is connected in a large area.

[0040] The bonding layer 121 is a metal material. For example, the material of the bonding layer 121 is Al and Al alloy. Specifically, the material of the bonding layer 121 is selected from at least one of Al, AlSi, AlSiCu, AlSiMg, and AlMgSiFe, but is not limited thereto.

[0041] The filling layer 122 can be a metal material or a non-metal material. Specifically, the filling layer 122 is a metal material, and the material thereof is selected from at least one of Cu, Ag, Au, and Pt, but is not limited thereto.

[0042] Alternatively, the filling layer 122 is a non-metallic material selected from at least one of the group consisting of graphite paper, carbon fiber, graphene and copper-coated graphene, but not limited thereto.

[0043] Alternatively, the material of the filling layer 122 is a high-temperature-resistant ceramic glue, and the vacuum high-temperature resistance is greater than 450℃.

[0044] The thickness of the bonding layer 121 is less than the thickness of the filling layer 122.

[0045] Preferably, the thickness of the bonding layer 121 ranges from 0.05mm to 0.2mm, and the thickness of the filling layer 122 ranges from 0.065mm to 0.25mm.

[0046] The edges of the bonding layer 121 and the filling layer 122 can overlap or not overlap. That is, the orthographic projection of the bonding layer 121 on the base 110 does not overlap with the orthographic projection of the filling layer 122 on the base 110; or the orthographic projection of the bonding layer 121 on the base 110 partially overlaps with the orthographic projection of the filling layer 122 on the base 110, and the overlapping area ranges from 0.5% to 10%.

[0047] The filling layer 122 can be deformed under a predetermined pressure, and the compression range of the filling layer 122 ranges from 5% to 30%.

[0048] The melting point of the bonding layer 121 is lower than the melting point of the filling layer 122. In the manufacturing process, the bonding layer 121 is connected with the base 110 and the ceramic disc 100 in the form of liquid phase, and the filling layer 122 is connected with the base 110 and the ceramic disc 100 in the form of solid state.

[0049] As shown in Figure 2 The connecting layer 120 includes a plurality of nested annular bonding sub-layers 1211 and a plurality of annular filling layers 122. At least one of the bonding sub-layers 1211 is provided with a plurality of air holes 130, and at least one of the filling layers 122 is provided with a plurality of Pin holes 135. The connecting layer 120 is further provided with a DC electrode hole (not shown), a heating electrode hole (not shown) and a temperature measuring hole (not shown).

[0050] In other embodiments, the bonding sub-layer 1211 can also be in a block or strip structure, and the filling layer 122 fills the gap between the adjacent two bonding sub-layers 1211.

[0051] As shown in Figures 1-3 The application further provides a manufacturing method of the electrostatic chuck as described above, which comprises the following steps:

[0052] Step 1: A ceramic disc 100 with embedded electrodes is prepared by using a high-temperature co-firing process.

[0053] Specifically, the ceramic disc 100 is composed of ceramic material and metal electrode. The ceramic powder is refined in particle size by ball milling, sand milling and other methods, and is mixed with dispersant, binder, plasticizer and the like. The obtained slurry is uniformly coated on the base band of the casting machine, and is dried to form a film with high density and good uniformity. The ceramic material is at least one of alumina, aluminum nitride, alumina-silicon carbide and aluminum nitride-silicon carbide, but is not limited to the above materials. After cutting, the green ceramic sheet is punched, and the electrode layer is prepared by screen printing metal slurry or in the form of metal film. The metal electrode includes an electrostatic electrode 105 and a heating electrode 106. Through the processes of lamination and warm isostatic pressing, the multi-layer casting sheet is tightly attached together to obtain a ceramic blank with electrode, and cutting processing is carried out for degreasing and sintering. The ceramic material and the metal are sintered to form the ceramic disc 100.

[0054] The preferred sintering method is hot pressing and hot isostatic pressing, and the sintering atmosphere can be selected from hydrogen, nitrogen, argon and vacuum. The bending strength of the ceramic disc 100 is > 350Mpa, and the thermal expansion coefficient is 4-7ppm / ℃. The diameter of the ceramic disc 100 is 296mm, and the thickness is 1mm-6mm.

[0055] Step 2, the base 110 is formed by hot pressing sintering and welding process.

[0056] Specifically, step 2 includes the following steps:

[0057] Step 201, uniformly mix Al-SiC or TiC by general powder mixing method.

[0058] Step 202, the mixed powder in the above step is sintered by hot pressing to form the base substrate.

[0059] Step 203, the base substrate is processed into a base component with Chiller passage and Gas passage structure.

[0060] Step 204, the base component is connected by brazing to form the base 110.

[0061] Step 205, a ceramic coating is formed on the surface of the base 110 by spraying, anodic oxidation, physical and chemical vapor deposition, and the thickness of the ceramic coating is 100μm-300μm.

[0062] Specifically, the base 110 is a metal matrix composite material mainly made of metal material such as aluminum, containing components such as SiC or TiC. The content of SiC or TiC is more than 80%. The base substrate is prepared by hot pressing, and the base has a flow channel for the passage of coolant, such as a Gas or Chiller flow channel structure. The Gas or Chiller is formed after machining and is integrated by welding. The thermal expansion coefficient of the base is 3-8 ppm / °C, and the bending strength is >300 Mpa. The surface of the base is coated with a ceramic coating by spraying; or an anodized layer is formed by anodizing; or a dense coating is formed by other physical or chemical deposition methods. The thermal expansion coefficient of the ceramic disc 100 is 4-7 ppm / °C, and the difference between the thermal expansion coefficients of the base 110 and the ceramic disc 100 is <2 ppm / °C at -100°C to 200°C. The diameter of the base is 300-350 mm, the thickness is 27-35 mm, and the bonding surface diameter is 296 mm.

[0063] Step 3, place a plurality of filler layers 122 on the upper surface of the base 110, and place a bonding layer 121 between the gaps between adjacent two filler layers 122, so that the filler layers 122 and the bonding layer 121 cover the upper surface of the base 110 to form a connecting layer 120.

[0064] Specifically, the base 110 is machined to the finished size, and the ceramic disc 100 is machined to the finished size. Then the filler layer 122 is placed on the upper surface of the base 110 and tightly adheres to the base 110. The bonding layer 121 is placed between the gaps between the filler layers 122. The upper surface of the base 110 is covered with the bonding layer 121 and the filler layer 122.

[0065] Step 4, place the ceramic disc 100 on the upper surface of the connecting layer 120, and assemble the base 110, the connecting layer 120 and the ceramic disc 100.

[0066] Step 5, place the assembled base 110, connecting layer 120 and ceramic disc 100 into a vacuum brazing device for vacuum brazing. The bonding layer 121 is heated and melted to tightly connect the base 110 and the ceramic disc 100, and the filler layer 122 is compressed and deformed under the preset pressure of the vacuum brazing device and tightly adheres to the base 110 and the ceramic disc 100.

[0067] Specifically, the assembled workpiece is placed in a vacuum brazing machine at a brazing temperature between 620℃ and 660℃ for 10 minutes. After the bonding layer 121 melts, it connects the ceramic disk 100 and the base 110. Simultaneously, the vacuum brazing applies pressure, compressing the filler layer 122 to ensure a seamless fit with the ceramic disk 100 and the base 110. The thickness of the bonding layer 121 is between 0.05 and 0.2 mm, and the thickness of the filler layer 122 is between 0.065 and 0.25 mm. After welding, the thickness uniformity of the electrostatic chuck bonding layer 120 is ±0.01 mm.

[0068] The electrostatic chuck and its manufacturing method of the present invention will be described in detail below with reference to specific embodiments.

[0069] Example 1

[0070] Combination Figure 1 and Figure 2 As shown, the ceramic disk 100 of the electrostatic chuck is made of AlN-SiC, with AlN having a particle size of 1 micrometer and SiC having a particle size of 0.05 micrometers. The SiC content is 2% (mass percentage), and the sintering aid Y2O3 content is 3% (mass percentage). The above powders are added to the organic additive system, mixed, and ball-milled for 24 hours, and then a ceramic film is obtained by tape casting. Electrodes are prepared on the ceramic film by screen printing, and ceramic blanks are formed by stacking. The ceramic blanks are degreased at 500℃ for 2 hours, and then sintered in a nitrogen atmosphere at 1780℃ for 2 hours, forming the ceramic disk 100 after processing.

[0071] The base 110 of the electrostatic chuck is made of Al-SiC, with Al powder having a particle size of 5 micrometers and SiC particles having a particle size of 0.5 micrometers. The SiC content is 75%. The Al-SiC substrate is prepared by hot pressing and sintering after uniform mixing in a ball mill for 24 hours. Gas channels and Chiller channels are then formed on the substrate. Vacuum brazing is performed at 620℃ for 10 minutes. The base is then machined and plasma-sprayed to form a 200 μm thick ceramic coating of Y2O3. After precision cleaning, the base 110 is formed.

[0072] The base 110 and the ceramic disc 100 are combined through the connecting layer 120. The material of the connecting layer 121 is selected as AlSiMgFe alloy. The material of the filling layer 122 is selected as graphite paper. The thickness of the graphite paper is 0.15 mm, and the thickness of the AlSiMg alloy is 0.12 mm. The AlSiMgFe sheet and the graphite paper are cut according to the design drawing requirements. The graphite paper and the AlSiMgFe alloy are laid flat on the upper surface of the base 110, and the AlSiMgFe alloy overlaps the graphite paper by 5%. The ceramic disc 100 is assembled with the base 110, the graphite paper and the AlSiMgFe alloy, and placed in a vacuum brazing furnace for integration. The welding temperature is selected as 570℃ / 10min. After welding, the electrostatic chuck is formed. After processing, the finished product is formed.

[0073] The mass spectrometer is used to detect the air tightness of the electrostatic chuck, and the air tightness reaches 1 E-10Pam3 / s. The tensile specimen is used to detect that the tensile strength of the connecting layer of the electrostatic chuck is 80Mpa. Under the condition of-100℃ to 400℃, the temperature uniformity of the electrostatic chuck is ±0.8℃; at the same time, the deformation amount of the electrostatic chuck is 0.015mm, and the connecting layer 120 between the ceramic disc 100 and the base 110 does not crack.

[0074] The following are examples 2-10 and comparative examples 1-2. The effects of examples 2-10 are verified by changing the material of the ceramic disc 100, the material of the base 110, the material of the connecting layer 121, the thickness of the connecting layer 121, the material of the filling layer 122 and the thickness of the filling layer 122. Table 1 below lists the technical effects achieved by examples 2-10 of the present application compared with comparative examples 1-2.

[0075] Table 1

[0076]

[0077] As can be seen from the above, the electrostatic chuck of the example of the present application has a significant improvement in air tightness, tensile strength and temperature uniformity compared with the electrostatic chuck of the comparative example. Moreover, the deformation amount of the electrostatic chuck of the present application is significantly reduced compared with the deformation amount of the electrostatic chuck of the comparative example. Therefore, the electrostatic chuck of the present application is stable and reliable in the low-temperature etching environment, significantly reduces the risk of deformation and cracking of the electrostatic chuck, and prolongs the service life.

[0078] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An electrostatic chuck, comprising: The ceramic disc, the base and the connecting layer between the ceramic disc and the base; The connecting layer comprises a bonding layer and a filling layer, the bonding layer and the filling layer are arranged in the same layer, the bonding layer comprises a plurality of bonding sub-layers arranged at intervals, and the filling layer fills the gaps between the bonding sub-layers to divide the stress field and reduce the extrusion on the ceramic disc when the bonding sub-layers expand; the bonding layer is a metal material; the melting point of the bonding layer is lower than that of the filling layer; The assembled base, connecting layer and ceramic disc are placed in a vacuum brazing device for vacuum brazing, the bonding layer is heated and melted to tightly connect the base and the ceramic disc, and the filling layer is compressed and deformed under the preset pressure of the vacuum brazing device and tightly adheres to the base and the ceramic disc.

2. The electrostatic chuck of claim 1, wherein, The material of the bonding layer is selected from at least one of Al, AlSi, AlSiCu, AlSiMg and AlMgSiFe.

3. The electrostatic chuck of claim 1, wherein, The filling layer deforms under the preset pressure, and the compression range of the filling layer is 5%-30%.

4. The electrostatic chuck of claim 1, wherein, The orthogonal projection of the bonding layer on the base does not overlap with the orthogonal projection of the filling layer on the base; Alternatively, the orthogonal projection of the bonding layer on the base partially overlaps with the orthogonal projection of the filling layer on the base, and the overlapping area ranges from 0.5% to 10%.

5. The electrostatic chuck of claim 1, wherein, The thickness of the bonding layer ranges from 0.05mm to 0.2mm, and the thickness of the filling layer ranges from 0.065mm to 0.25mm.

6. The electrostatic chuck of claim 1, wherein, The material of the filling layer is selected from at least one of Cu, Ag, Au and Pt, or the material of the filling layer is selected from at least one of graphite paper, carbon fiber, graphene and copper-coated graphene, or the material of the filling layer is ceramic glue.

7. The electrostatic chuck of claim 1, wherein, The bonding sub-layer has a ring, block or strip structure.

8. A method of manufacturing an electrostatic chuck as claimed in any one of claims 1-7, characterized in that, The method comprises the following steps: Step 1: obtaining an inner-embedded electrode ceramic disc by high-temperature co-firing process; Step 2: forming a base by hot-pressing sintering and welding process; Step 3: placing a plurality of filling layers at intervals on the upper surface of the base, and placing a bonding layer between adjacent two filling layers, so that the filling layers and the bonding layer cover the upper surface of the base to form a connecting layer; Step 4: placing the ceramic disc on the upper surface of the connecting layer, and assembling the base, the connecting layer and the ceramic disc; Step 5: placing the assembled base, connecting layer and ceramic disc in a vacuum brazing device for vacuum brazing, the bonding layer is heated and melted to tightly connect the base and the ceramic disc, and the filling layer is compressed and deformed under the preset pressure of the vacuum brazing device and tightly adheres to the base and the ceramic disc.

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