Electrostatic Chuck and its Manufacturing Method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-15
- Publication Date
- 2026-08-14
AI Technical Summary
设计台阶导致区域电阻在台阶处和台阶周围的凹陷不同出现不同大小的吸附力(即均衡性差)，由于晶片本身是非常薄，这种不同大小的吸附力会加大晶片的破片、裂片、变形的风险
[0010]本公开的有益效果如下：在本公开的静电卡盘以及静电卡盘制作方法制备的静电卡盘中，全部绞结区形成共面的且为水平的绞结区顶面和共面的且为水平的绞结区底面，间格区底面和绞结区底面共面，绞结区顶面相对间格区顶面朝向介电层突出，在厚度方向上，各间格区与介电层的对应的凸起对齐，各绞结区与介电层的对应的凹陷对齐，这样，晶片与凸起之间的接触面到电极层的与凸起对应的间格区顶面的距离会大于晶片的底面到电极层的与凹陷对应的绞结区顶面的距离，凸起处的静电吸附力与凹陷处的静电吸附力之间的差异就会减小(即均衡性改善)，进而降低晶片的破片、裂片、变形的风险，提高晶片在对应的工序(例如蚀刻、沉积等)过程中的生产良率，降低成本增加生产效益。
Smart Images
Figure CN116759364B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the semiconductor field, and more specifically to an electrostatic chuck and a method for manufacturing the same. Background Technology
[0002] In the semiconductor IC manufacturing process, electrostatic chucks (ESCs or E-Chucks) are generally used to fix, support, and transfer wafers and control their temperature during etching, magnetron sputtering (PVD), chemical vapor deposition (CVD), and ion implantation. Maintaining uniform temperature in each area of the wafer directly determines the quality of the process. It is also necessary to maintain balanced stress on the wafer in each area of the E-Chuck to avoid uneven adsorption forces in the E-Chuck areas, which could lead to wafer breakage or deformation.
[0003] The main processes currently used to manufacture E-Chucks are:
[0004] 1. An electrode layer is sintered in the hot ceramic, and the temperature is controlled by water cooling in combination with the alloy base (i.e., the external cooling mechanism). In order to make the chip conduct heat evenly and quickly, most of them use ceramic materials with high thermal conductivity (Al2O3 ceramic, AlN ceramic) and embed an electrode layer inside.
[0005] 2. At the same time, some metal elements are doped into the ceramic (i.e. dielectric layer) above the electrode layer to reduce the resistivity of the dielectric layer. This makes the dielectric layer not an ideal insulating layer. The contact surface between the dielectric layer and the wafer is not an ideal plane. The roughness of the two planes cannot be ignored, and the contact resistance is much greater than the dielectric layer resistance.
[0006] 3. More uniform heat conduction: Heat transfer between the ceramic (dielectric layer) and the wafer is achieved through helium convection. Therefore, various patterned steps (also known as protrusions) are designed on the surface of the dielectric layer to ensure sufficient helium convection for heat dissipation. The design of the steps results in different resistivity at the step and in the depressions around the step, leading to varying degrees of adsorption forces (i.e., poor uniformity). Since the wafer itself is very thin, these varying adsorption forces increase the risk of wafer breakage, cracking, and deformation. Summary of the Invention
[0007] In view of the problems existing in the background art, one object of this disclosure is to provide an electrostatic chuck and a method for manufacturing the same, which can improve the balance of electrostatic adsorption force at the protrusions and the electrostatic adsorption force at the recesses of the electrostatic chuck, thereby reducing the risk of wafer breakage, cracking and deformation.
[0008] Therefore, an electrostatic chuck is provided, which includes a dielectric layer, an electrode layer, a base, and electrodes. The dielectric layer, electrode layer, and base are stacked along the thickness direction. The electrode layer is embedded between the dielectric layer and the base, and the electrodes are electrically connected to the electrode layer and exposed from the base. The surface of the dielectric layer is distributed with patterned grid-like protrusions and depressions. The tops of the protrusions are horizontal, and the bottoms of the depressions are horizontal. Each protrusion is surrounded by a corresponding depression, and all depressions are interconnected. The electrode layer is a grid woven from metal wires. The grid includes inter-cell regions and stranded regions. There are no overlapping metal wires in the thickness direction in the inter-cell regions, but there are overlapping metal wires in the thickness direction in the stranded regions. Each inter-cell region is surrounded by a corresponding stranded region. All inter-cell regions form a coplanar and horizontal top surface and a coplanar and horizontal bottom surface. All stranded regions are connected together. All stranded regions form a coplanar and horizontal top surface and a coplanar and horizontal bottom surface. The bottom surfaces of the inter-cell regions and the stranded regions are coplanar. The top surface of the stranded region protrudes towards the dielectric layer relative to the top surface of the inter-cell regions. In the thickness direction, each inter-cell region is aligned with its corresponding protrusion in the dielectric layer, and each stranded region is aligned with its corresponding depression in the dielectric layer.
[0009] A method for manufacturing an electrostatic chuck includes the following steps: S1, pouring a slurry into a mold and sintering it into a base with through holes; S2, polishing the surface of the base; S3, placing a wire mesh-like electrode layer on the surface of the base, the mesh including interstices and stranded areas, wherein there are no overlapping metal wires in the thickness direction in the interstices, and there are overlapping metal wires in the thickness direction in the stranded areas, each interstices being surrounded by a corresponding stranded area, all interstices forming a coplanar and horizontal top surface and a coplanar and horizontal bottom surface, all stranded areas being connected to each other, all stranded areas forming a coplanar and horizontal top surface and a coplanar and horizontal bottom surface, and the bottom surface of the interstices... The top surface of the electrode layer and the bottom surface of the stranded area are coplanar, and the top surface of the stranded area protrudes towards the dielectric layer relative to the top surface of the interlayer area; S4, a dielectric layer slurry is poured onto the surface of the electrode layer and sintered to form the dielectric layer, so that the electrode layer is embedded between the dielectric layer and the base and forms an electrostatic chuck blank; S5, the surface of the dielectric layer of the electrostatic chuck blank is patterned to form a grid of protrusions and depressions, the top of the protrusions is a horizontal plane, the bottom of the depressions is a horizontal plane, each protrusion is surrounded by a corresponding depression, and all depressions are interconnected. In the thickness direction, each interlayer area is aligned with the corresponding protrusion of the dielectric layer, and each stranded area is aligned with the corresponding depression of the dielectric layer; S6, the electrode is passed through the through hole and the electrode and the electrode layer are electrically connected, thereby preparing the electrostatic chuck.
[0010] The beneficial effects of this disclosure are as follows: In the electrostatic chuck and the electrostatic chuck prepared by the electrostatic chuck manufacturing method of this disclosure, all stranded regions form a coplanar and horizontal top surface and a coplanar and horizontal bottom surface of the stranded regions. The bottom surface of the interlayer region is coplanar with the bottom surface of the stranded region. The top surface of the stranded region protrudes towards the dielectric layer relative to the top surface of the interlayer region. In the thickness direction, each interlayer region is aligned with the corresponding protrusion of the dielectric layer, and each stranded region is aligned with the corresponding recess of the dielectric layer. In this way, the distance from the contact surface between the wafer and the protrusion to the top surface of the interlayer region corresponding to the protrusion of the electrode layer will be greater than the distance from the bottom surface of the wafer to the top surface of the stranded region corresponding to the recess of the electrode layer. The difference between the electrostatic adsorption force at the protrusion and the electrostatic adsorption force at the recess will be reduced (i.e., the uniformity is improved), thereby reducing the risk of wafer breakage, cracking, and deformation, improving the production yield of the wafer in the corresponding process (such as etching, deposition, etc.), reducing costs and increasing production efficiency. Attached Figure Description
[0011] Figure 1 This is a cross-sectional view of the electrostatic chuck according to the present disclosure, with the wafer shown for ease of illustration.
[0012] Figure 2 This is a 3D diagram of an electrostatic chuck.
[0013] Figure 3 yes Figure 2 Top view.
[0014] Figure 4 yes Figure 2 A three-dimensional image viewed from below.
[0015] Figure 5 This is a top view of the electrode layer of an electrostatic chuck.
[0016] Figure 6 This is a schematic diagram of the electrode layer used to illustrate the interlayer and twisted regions of the electrode layer.
[0017] Figure 7 This is a schematic diagram of the principle of an electrostatic chuck.
[0018] Figure 8 This is the equivalent circuit diagram of an electrostatic chuck.
[0019] The reference numerals in the attached figures are explained below.
[0020] 100 electrostatic chuck B21 compartment bottom surface
[0021] Td thickness direction 22 knotted area
[0022] 1. Top surface of the T22 stranded region of dielectric layer
[0023] 11. Bottom surface of the B22 protrusion knot area
[0024] 12 recessed bases
[0025] 13-hole helium gas port, 31-hole port
[0026] 2 electrode layers 32 perforations
[0027] 20 metal wire 4 electrodes
[0028] 21 compartments, 200 chips
[0029] Top surface of T21 grid area Detailed Implementation
[0030] The accompanying drawings illustrate embodiments of this disclosure, and it will be understood that the disclosed embodiments are merely examples of this disclosure, which can be implemented in various forms. Therefore, the specific details disclosed herein should not be construed as limiting, but are intended only as the basis for the claims and as an illustrative basis to teach those skilled in the art how to implement this disclosure in various ways.
[0031] [Electrostatic Chuck]
[0032] Reference Figures 1 to 6 The electrostatic chuck 100 according to this disclosure includes a dielectric layer 1, an electrode layer 2, a base 3, and an electrode 4. The dielectric layer 1, electrode layer 2, and base 3 are stacked along the thickness direction Td. The electrode layer 2 is embedded between the dielectric layer 1 and the base 3. The electrode 4 is electrically connected to the electrode layer 2 and exposed from the base 3. The surface of the dielectric layer 1 has patterned grid-like protrusions 11 and recesses 12. The top of the protrusions 11 is horizontal, and the bottom of the recesses 12 is horizontal. Each protrusion 11 is surrounded by a corresponding recess 12, and all recesses 12 are interconnected. The electrode layer 2 is a grid woven from metal wires 20. The grid structure includes interstices 21 and stranded regions 22. No metal wires 20 are stacked in the thickness direction Td within the interstices 21, while metal wires 20 are stacked in the thickness direction Td within the stranded regions 22. Each interstice 21 is surrounded by a corresponding stranded region 22. All interstices 21 form a coplanar and horizontal top surface T21 and a coplanar and horizontal bottom surface B21. All stranded regions 22 are interconnected, forming a coplanar and horizontal top surface T22 and a coplanar and horizontal bottom surface B22. The bottom surface B21 of the interstices and the bottom surface B22 of the stranded regions are coplanar. The top surface T22 of the stranded regions protrudes towards the dielectric layer 1 relative to the top surface T21 of the interstices. In the thickness direction Td, each interstice 21 is aligned with its corresponding protrusion 11 in the dielectric layer 1, and each stranded region 22 is aligned with its corresponding recess 12 in the dielectric layer 1.
[0033] Under the voltage (i.e. DC voltage) applied to the electrodes 4 of the electrostatic chuck 100 and the wafer 200 during the electrostatic adsorption operation, the wafer 200 is electrostatically adsorbed onto the electrostatic chuck 100 and supported by the protrusions 11 distributed on the surface of the dielectric layer 1. All the recesses 12 that are interconnected provide channels for external helium gas flow to cool the electrostatic chuck 100 and the wafer 200.
[0034] Regarding electrostatic adsorption, the principle of electrostatic adsorption force at the protrusion 11 and the depression 12 is as follows: Figure 7 and Figure 8 As shown.
[0035] The electrostatic attraction force of the electrostatic chuck 100 is:
[0036] Formula 1: F = F1 + F2
[0037] Wherein: F1 is the electrostatic adsorption force generated at the protrusion 11, and F2 is the electrostatic adsorption force generated at the depression 12. For ease of explanation, only one protrusion 12 and its adjacent depression 12 are used as examples.
[0038]
[0039] Where A1 is the area of the portion of electrode layer 2 corresponding to protrusion 11, ε is the dielectric constant of dielectric layer 1, and V 11 d1 is the voltage drop at protrusion 11, and d1 is the distance from the contact surface between the wafer 200 and protrusion 11 to the portion of electrode layer 2 corresponding to protrusion 11.
[0040]
[0041] Where A2 is the area of the portion of electrode layer 2 corresponding to recess 12, V R2 d1 is the voltage drop at the recess 12, and d2 is the distance from the bottom surface of the wafer 200 to the portion of the electrode layer 2 corresponding to the recess 12.
[0042] Because the contact between wafer 200 and bump 11 is not a perfectly planar one, there is a certain degree of roughness between them. The contact resistance R1 at bump 11 is much greater than the volume resistance R2 at depression 12. Figure 8 In the circuit with the same current, the voltage drop V at bulge 11 is... R1 Much greater than the voltage drop V of the volume resistivity at the 12th depression. R2 ,
[0043] When A1 and A2 are the same, and d1 and d2 are the same, since ε is the same, the relative relationship between F1 and F2 is only reflected in V. R1 and V R2 The relationship. When A1 and A2 are the same, and d1 and d2 are the same, due to the pressure drop V... R1>> R2 Therefore, F1 >> F2. This results in a significant difference between the electrostatic adsorption force F1 at the protrusion 11 and the electrostatic adsorption force F2 at the depression 12, which increases the risk of chip breakage, cracking, and deformation of the wafer 200.
[0044] In the electrostatic chuck 100 disclosed herein, all stranded regions 22 form a coplanar and horizontal top surface T22 and a coplanar and horizontal bottom surface B22. The bottom surface B21 of the interlayer region and the bottom surface B22 of the stranded region are coplanar. The top surface T22 of the stranded region protrudes toward the dielectric layer 1 relative to the top surface T21 of the interlayer region. In the thickness direction Td, each interlayer region 21 is aligned with the corresponding protrusion 11 of the dielectric layer 1, and each stranded region 22 is aligned with the corresponding recess 12 of the dielectric layer 1. Thus, the contact surface between the wafer 200 and the protrusion 11 extends to the interlayer region of the electrode layer 2 corresponding to the protrusion 11. The distance d1 from the top surface T21 will be greater than the distance d2 from the bottom surface of the wafer 200 to the top surface T22 of the stranded area corresponding to the recess 12 in the electrode layer 2. Based on formulas 2 and 3, F1 will decrease and F2 will increase. Thus, the difference between the electrostatic adsorption force F1 at the protrusion 11 and the electrostatic adsorption force F2 at the recess 12 will be reduced (i.e., the balance between F1 and F2 is improved), thereby reducing the risk of wafer breakage, cracking, and deformation, improving the production yield of wafer 200 in the corresponding process (such as etching, deposition, etc.), reducing costs and increasing production efficiency.
[0045] Furthermore, the total area of all grid regions 21 is smaller than the total area of all stranded regions 22. This is equivalent to a decrease in A1 in Formula 2 and an increase in A2 in Formula 3. As a result, based on the aforementioned d1 and d2, F1 further decreases and F2 further increases. Consequently, the difference between the electrostatic adsorption force F1 at the protrusion 11 and the electrostatic adsorption force F2 at the depression 12 is further reduced (i.e., the balance between F1 and F2 is further improved), thereby further reducing the risk of wafer 200 breakage, cracking, and deformation. The total area of all grid regions 21 can be evenly distributed according to the number of grid regions 21, and the total area of all stranded regions 22 can be evenly distributed according to the number of stranded regions 22.
[0046] Reference Figure 3 and Figure 4The dielectric layer 1 is provided with a helium gas passage 13, which penetrates the dielectric layer 1 along the thickness direction Td. The base 3 is also formed with a through hole 31 and a through hole 32. The through hole 31 is for inserting the electrode 4, and the through hole 32 is used to install a helium gas conduit (not shown). The through hole 32 communicates with the helium gas passage 13 through the corresponding interstices 21 of the electrode layer 2, or the through hole 32 communicates with the helium gas passage 13 through the space occupied by the unstacked metal wires 20 in the corresponding interstices 21 and the corresponding stranded area 22 of the electrode layer 2. External helium gas reaches the electrode layer 2 through the conduit and reaches the surface of the dielectric layer 1 through the through hole 32. Then, it contacts the bottom surface of the wafer 200 through all the interconnected recesses 12 on the surface of the dielectric layer 1, thereby cooling the wafer 200. Of course, in order to enhance heat dissipation, a separate helium gas can also be introduced into the surface of the dielectric layer 1 and flow through all the interconnected recesses 12 on the surface of the dielectric layer 1 to cool the wafer 200.
[0047] like Figure 3 As shown, the helium gas inlet 13 is a two-dimensional array of pinholes. Figure 3 In the dielectric layer 1, helium gas passages 13 are provided at four spaced locations, but any number of helium gas passage regions 13 can be arranged as needed.
[0048] The dielectric layer 1 of the electrostatic chuck 100 and the base 3 can be made of the same ceramic material (e.g., Al2O3 ceramic, AlN ceramic), but as described in the background art, the dielectric layer 1 can be doped as needed. Furthermore, as described in the background art, for temperature control, the electrostatic chuck 100 can be provided with an additional external cooling mechanism (i.e., located below the base 3) to further enhance temperature control.
[0049] [Method for making an electrostatic chuck]
[0050] Combination Figures 1 to 6 The method for manufacturing an electrostatic chuck according to this disclosure includes the following steps:
[0051] Step S1: Pour the slurry into the mold and sinter it to form a base 3 with through holes 31;
[0052] S2, polish the surface of base 3;
[0053] S3, place the mesh-like electrode layer 2 woven from metal wires 20 on the surface of the base 3. The mesh includes inter-cell regions 21 and stranded regions 22. There are no metal wires 20 stacked in the thickness direction Td in the inter-cell regions 21, and there are metal wires 20 stacked in the thickness direction Td in the stranded regions 22. Each inter-cell region 21 is surrounded by a corresponding stranded region 22. All inter-cell regions 21 form a coplanar and horizontal top surface T21 and a coplanar and horizontal bottom surface B21. All stranded regions 22 are connected to each other. All stranded regions 22 form a coplanar and horizontal top surface T22 and a coplanar and horizontal bottom surface B22. The bottom surface B21 of the inter-cell region and the bottom surface B22 of the stranded region are coplanar. The top surface T22 of the stranded region protrudes toward the dielectric layer 1 relative to the top surface T21 of the inter-cell region.
[0054] S4, pour dielectric layer slurry onto the surface of electrode layer 2 and sinter to form dielectric layer 1, so that electrode layer 2 is embedded between dielectric layer 1 and base 3 and forms electrostatic chuck blank.
[0055] S5, the surface of the dielectric layer 1 of the electrostatic chuck blank is patterned to form a grid of protrusions 11 and recesses 12. The top of the protrusions 11 is a horizontal plane and the bottom of the recesses 12 is a horizontal plane. Each protrusion 11 is surrounded by a corresponding recess 12. All the recesses 12 are connected to each other. In the thickness direction Td, each grid area 21 is aligned with the corresponding protrusion 11 of the dielectric layer 1, and each stranded area 22 is aligned with the corresponding recess 12 of the dielectric layer 1.
[0056] S6, the electrode 4 is passed through the through hole 31 and the electrode 4 and the electrode layer 2 are electrically connected, thereby preparing the aforementioned electrostatic chuck 100.
[0057] The slurry used for the base in step S1 is a ceramic (Al2O3 ceramic, AlN ceramic) slurry.
[0058] In one example, in step S2, the surface of the base 3 is polished by machining.
[0059] In one example, in step S1, the base 3 is also formed with a through hole 32 for installing a helium gas pipe; in step S5, a helium gas through hole 13 that leads directly to the electrode layer 2 is also machined on the surface of the dielectric layer 1 of the electrostatic chuck blank; the through hole 32 is connected to the helium gas through hole 13 through the corresponding intersticer 21 of the electrode layer 2, or the through hole 32 is connected to the helium gas through hole 13 through the space occupied by the unstacked metal wire 20 in the corresponding stranded area 22 of the electrode layer 2 via the corresponding intersticer 21 of the electrode layer 2.
[0060] In step S3, the mesh-like electrode layer 2 woven by the metal wire 20 can be made using any known weaving technique. Metal wire weaving is a very mature technology, as long as the relative structure and position of the twisted area 22 and the intersticed area 21 of the mesh-like metal wire 20 are satisfied.
[0061] The dielectric layer paste in step S4 is a ceramic (Al2O3 ceramic, AlN ceramic) paste. Of course, as mentioned above, it can be doped according to actual needs.
[0062] In one example, in step S5, the surface patterning of the dielectric layer 1 of the electrostatic chuck blank is performed by machining.
[0063] In one example, the electrostatic chuck manufacturing method further includes the step of cleaning the surface of the dielectric layer 1 of the electrostatic chuck blank after step S5 between steps S5 and S6.
[0064] It should be noted that the specific features, effects, and principles of the electrostatic chuck 100 prepared by the electrostatic chuck manufacturing method disclosed herein will not be repeated here.
[0065] Several exemplary embodiments have been described in detail above, but this document is not intended to limit itself to the explicitly disclosed combinations. Therefore, unless otherwise stated, the various features disclosed herein can be combined to form several other combinations, which are not shown for simplicity.
Claims
1. An electrostatic chuck, the electrostatic chuck (100) comprising a dielectric layer (1), an electrode layer (2), a base (3), and an electrode (4), wherein the dielectric layer (1), the electrode layer (2), and the base (3) are stacked along the thickness direction (Td), the electrode layer (2) is embedded between the dielectric layer (1) and the base (3), and the electrode (4) is electrically connected to the electrode layer (2) and exposed from the base (3), characterized in that, The surface of the dielectric layer (1) is distributed with patterned grid-like protrusions (11) and depressions (12). The top of the protrusions (11) is a horizontal plane, the bottom of the depressions (12) is a horizontal plane, each protrusion (11) is surrounded by a corresponding depression (12), and all the depressions (12) are connected to each other. The electrode layer (2) is a mesh woven from metal wires (20); The grid includes inter-cell regions (21) and stranded regions (22). There are no metal wires (20) stacked in the thickness direction (Td) in the inter-cell regions (21), and there are metal wires (20) stacked in the thickness direction (Td) in the stranded regions (22). Each inter-cell region (21) is surrounded by a corresponding stranded region (22). All inter-cell regions (21) form a coplanar and horizontal top surface (T21) and a coplanar and horizontal bottom surface (B21) of the inter-cell regions. All stranded regions (22) are connected to each other. All stranded regions (22) form a coplanar and horizontal top surface (T22) and a coplanar and horizontal bottom surface (B22) of the stranded regions. The bottom surface (B21) of the inter-cell regions and the bottom surface (B22) of the stranded regions are coplanar. The top surface (T22) of the stranded regions protrudes toward the dielectric layer (1) relative to the top surface (T21) of the inter-cell regions. In the thickness direction (Td), each inter-cell region (21) is aligned with the corresponding protrusion (11) of the dielectric layer (1), and each stranded region (22) is aligned with the corresponding recess (12) of the dielectric layer (1).
2. The electrostatic chuck according to claim 1, characterized in that, The total area of all interspaces (21) is less than the total area of all knotted areas (22).
3. The electrostatic chuck according to claim 1, characterized in that, A helium passage (13) is provided at the recess (12) of the dielectric layer (1), and the helium passage (13) penetrates the dielectric layer (1) along the thickness direction (Td). The base (3) also has a through hole (31) and a perforation (32), the through hole (31) for inserting the electrode (4) and the perforation (32) for installing a pipe for helium gas; The perforation (32) communicates with the helium passage (13) through the space occupied by the unstacked metal wire (20) in the corresponding stranded area (22) of the electrode layer (2).
4. The electrostatic chuck according to claim 1, characterized in that, The helium gas inlet (13) is a pinhole distributed in a two-dimensional array.
5. A method for manufacturing an electrostatic chuck, characterized in that, Including the following steps: S1, pour the slurry into the mold and sinter it into a base (3) with through holes (31). S2, polish the surface of the base (3); S3, a mesh-like electrode layer (2) woven from metal wires (20) is placed on the surface of the base (3). The mesh includes inter-cell areas (21) and stranded areas (22). In the inter-cell areas (21), no metal wires (20) are stacked in the thickness direction (Td). In the stranded areas (22), metal wires (20) are stacked in the thickness direction (Td). Each inter-cell area (21) is surrounded by a corresponding stranded area (22). All inter-cell areas (21) are coplanar and are The top surface (T21) of the horizontal grid area and the bottom surface (B21) of the coplanar and horizontal grid area are connected together. All the twisted areas (22) form a top surface (T22) of the coplanar and horizontal twisted area and a bottom surface (B22) of the coplanar and horizontal twisted area. The bottom surface (B21) of the grid area and the bottom surface (B22) of the twisted area are coplanar. The top surface (T22) of the twisted area protrudes toward the dielectric layer (1) relative to the top surface (T21) of the grid area. S4, pour dielectric slurry onto the surface of electrode layer (2) and sinter to form dielectric layer (1) so that electrode layer (2) is embedded between dielectric layer (1) and base (3) and forms electrostatic chuck blank; S5, the surface of the dielectric layer (1) of the electrostatic chuck blank is patterned to form a grid of protrusions (11) and recesses (12). The top of the protrusions (11) is a horizontal plane, the bottom of the recesses (12) is a horizontal plane, each protrusion (11) is surrounded by a corresponding recess (12), all the recesses (12) are connected to each other, and in the thickness direction (Td), each grid area (21) is aligned with the corresponding protrusion (11) of the dielectric layer (1), and each twisted area (22) is aligned with the corresponding recess (12) of the dielectric layer (1). S6, the electrode (4) is passed through the through hole (31) and the electrode (4) and the electrode layer (2) are electrically connected, thereby preparing the electrostatic chuck (100) according to any one of claims 1-4.
6. The method for manufacturing an electrostatic chuck according to claim 5, characterized in that, The total area of all interspaces (21) is less than the total area of all knotted areas (22).
7. The method for manufacturing an electrostatic chuck according to claim 5, characterized in that, In step S2, the surface of the base (3) is polished by machining.
8. The method for manufacturing an electrostatic chuck according to claim 5, characterized in that, In step S5, the surface patterning of the dielectric layer (1) of the electrostatic chuck blank is performed by machining.
9. The method for manufacturing an electrostatic chuck according to claim 5, characterized in that, In step S1, the base (3) is also formed with a perforation (32) for installing a pipe for helium gas; In step S5, a helium gas passage (13) that leads directly to the electrode layer (2) is also machined on the surface of the recess (12) of the dielectric layer (1) of the electrostatic chuck blank. The perforation (32) communicates with the helium passage (13) through the space occupied by the unstacked metal wire (20) in the corresponding stranded area (22) of the electrode layer (2).
10. The method for manufacturing an electrostatic chuck according to claim 5, characterized in that, The electrostatic chuck manufacturing method further includes the following step between step S5 and step S6: The surface of the dielectric layer (1) of the electrostatic chuck blank after step S5 is cleaned.
Citation Information
Patent Citations
Sensor system for multi-zone electrostatic chuck
CN108474694A
Electrostatic chuck
CN109564890A