Electrostatic adsorption device, warp correction method, and mounting method

Abstract

The purpose of the present invention is to provide an electrostatic adsorption device with improved curved-surface adaptation, and a warp correction method and mounting method using the same.　Provided is an electrostatic adsorption device constructed to electrostatically adsorb an object to be adsorbed, the electrostatic adsorption device comprising a structure and an electrode member, wherein the structure is constructed to enable at least a part thereof to be deformed to form a curved portion, which is curved from one side to the other side in a first direction that is a direction parallel to a plane orthogonal to the thickness direction of the structure, wherein the electrode member is provided so as to be at least partially covered with the structure, wherein the electrode member has an adsorption surface for electrostatically adsorbing the object to be adsorbed, and wherein the adsorption surface of the electrode member is disposed at a position corresponding to the curvature of the curved portion in a curved state in which the curved portion is formed in the structure.

Description

Electrostatic adsorption device, warp correction method, and mounting method

[0001] The present invention relates to an electrostatic adsorption device, a warp correction method, and an attachment method.

[0002] Patent Literature 1 discloses an electrostatic chuck (electrostatic chuck) that attracts and holds a substrate (object) having a flat surface. The electrostatic chuck attracts and releases the object by utilizing electrostatic force acting between the device and the object when a voltage is applied. That is, the electrostatic chuck attracts the object by generating a potential difference between the device and the object using electrodes.

[0003] Japanese Patent Application Laid-Open No. 2007-109827

[0004] If the surface to which the object to be attracted is not flat, there is a concern that the electrostatic attraction device of Patent Document 1 may not be able to properly attract the object to be attracted.

[0005] An object of the present invention is to provide an electrostatic chuck device with improved curved surface adaptability (the ability to properly attract an object even if the surface to which the object is attracted is curved), and to provide a warp correction method and an attachment method using the same.

[0006] According to the present invention, there is provided an electrostatic adsorption device configured to electrostatically adsorb an object to be adsorbed, comprising a structure and an electrode member, wherein the structure is configured so that a curved portion can be formed by deformation of at least a portion of the structure, the curved portion is curved from one side to the other side in a first direction, the first direction is a direction parallel to a plane perpendicular to a thickness direction of the structure, the electrode member is arranged so that at least a portion of the electrode member is covered by the structure, and the electrode member has an adsorption surface for electrostatically adsorbing the object to be adsorbed, and the adsorption surface of the electrode member is positioned at a position corresponding to the curvature of the curved portion when the structure is in a curved state in which the curved portion is formed.

[0007] According to the present invention, the electrode member is provided so that at least a portion thereof is covered by a structure capable of forming a curved portion, and therefore the electrode member is provided integrally with the structure. As a result, when a curved portion is formed in the structure (when the structure is curved), the electrode member moves accordingly, and the suction surface of the electrode member is positioned at a position corresponding to the curvature of the curved portion. As a result, in the present invention, the suction surface of the electrode member can be positioned along the curved surface of the object to be suctioned, corresponding to the curvature of the curved portion, thereby improving the ability to adapt to curved surfaces.

[0008] FIG. 1A is an exploded perspective view of an electrostatic attraction device 100 according to an embodiment, and FIG. 1B is a perspective view of the electrostatic attraction device 100 shown in FIG. 1A . FIGS. 1A and 1B are perspective views of the attraction surface side of the electrostatic attraction device 100. FIG. 2A is a plan view of the structure 10 shown in FIG. 1A as seen from the attraction surface side of the electrostatic attraction device 100. FIG. 2B is a plan view of the structure 10 shown in FIG. 2A as seen from the opposite side to FIG. 2A . FIG. 2C is a side view of the structure 10 shown in FIG. 2A as seen from the direction corresponding to arrow A. FIG. 3A schematically shows the first plate-shaped portion 2A with a solid line and the second plate-shaped portion 2B with a dashed line to easily distinguish the components of the structure 10 shown in FIG. 2A . For ease of explanation, the third plate-shaped portion 2C is not shown in FIG. 3A . FIG. 3B is a diagram illustrating the third plate-shaped portion 2C, a component of the structure 10 shown in FIG. 2A . FIG. 4A is a perspective view of the structure 10 shown in FIG. 2A , and FIG. 4B is an enlarged view of region B shown in FIG. 4A . FIG. 4C is an enlarged view of the structure 10 shown in FIG. 2A . FIG. 5A is a perspective view of one electrode member 20 arranged at approximately the center of the structure 10, and FIG. 5B is an enlarged view of region B shown in FIG. 5A . FIG. 6A is a bottom view of the electrode member 20 (viewed from the opposite side of the adsorption surface 20A1). FIG. 6B is a top view of the electrode member 20 (viewed from the adsorption surface 20A1 side). FIG. 6C is a front view of the electrode member 20. FIG. 6D is a perspective view of the electrode member 20. FIG. 7 is a diagram for explaining the movement of the position of the adsorption surface of the electrode member 20 when the electrostatic adsorption device 100 transitions from a flat state to a curved state. In FIG. 7 , for convenience of explanation, the electrostatic adsorption device 100 is indicated by a dashed line, and the imaginary plane Sr is indicated by a solid line. FIG. 8A is a perspective view of the electrostatic attraction device 100 in a curved state. FIG. 8B is an enlarged view of the surface of the electrostatic attraction device 100 on the attraction surface side shown in FIG. 8A. FIG. 8C is an enlarged view of the surface of the electrostatic attraction device 100 opposite the attraction surface side (the surface opposite to the view shown in FIG. 8B). FIGS. 9A to 9C are diagrams illustrating the relationship between tensile stress and Poisson's ratio. FIG. 10A is a plan view of a prototype electrostatic attraction device 100 as seen from the attraction surface side. FIG. 10B is a perspective view of the electrostatic attraction device 100 shown in FIG. 10A.FIG. 10C is an enlarged view showing the state (planar state) of the electrostatic adsorption device structure 10 shown in FIG. 10A before deformation, and FIG. 10D is an enlarged view showing the state (curved state) after deformation. FIG. 10E is a perspective view showing the state (curved state) of the electrostatic adsorption device structure 10 shown in FIG. 10A after deformation. FIG. 11A is a view showing the state before horizontal tensile stress is applied to the structure 10 shown in FIG. 10A. FIG. 11B is a view showing the state in which horizontal tensile stress is applied to the structure 10 shown in FIG. 11A and the structure 10 is stretched horizontally by 10 mm. FIG. 11C is a view showing the state in which further horizontal tensile stress is applied from the state shown in FIG. 11B and the structure is stretched horizontally by 20 mm. FIGS. 12A and 12B are views showing the state before bending stress is applied to the structure 10 shown in FIG. 10A. The viewing angles are different between FIGS. 12A and 12B. 12C and 12D are diagrams showing a state in which a bending stress is applied to the structure 10 shown in FIG. 12A to form a curved portion in the structure 10, and the radius of curvature of the imaginary surface of the curved portion (see FIG. 7) is set to R200 mm. The viewing angles are different between FIGS. 12C and 12D. FIGS. 12E and 12F are diagrams showing a state in which the structure 10 shown in FIG. 12B is further curved to form a curved portion with a radius of curvature of the imaginary surface of the curved portion of R100 mm. The viewing angles are different between FIGS. 12E and 12F. FIGS. 13A to 13C are diagrams corresponding to FIGS. 11A to 11C, respectively. While FIGS. 13A to 13C show an electrode member 20 disposed on the structure 10, FIGS. 11A to 11C show no electrode member 20 disposed on the structure 10. FIGS. 14A to 14C are diagrams corresponding to FIGS. 12A to 12C, respectively. In Figures 14A to 14C, an electrode member 20 is arranged on the structure 10, but in Figures 12A to 12C, an electrode member 20 is not arranged on the structure 10. Figure 15 is a diagram showing the state of a film attracted by an electrostatic attraction device 100. Figures 16A and 16B are diagrams for explaining a calculation formula for performing bending deformation while keeping the inside dimensions of the peripheral edges of an auxetic structure constant. Figures 17A and 17B are schematic diagrams for explaining modified example 1-1 of the structure 10. Figures 17C and 17D are schematic diagrams for explaining modified example 1-2 of the structure 10. Figures 17E and 17F are schematic diagrams for explaining modified example 1-3 of the structure 10.18A and 18B are diagrams showing how the structure of Modification 1-1 shown in FIGS. 17A and 17B deforms. FIGS. 18C and 18D are diagrams showing how the structure of Modification 1-2 shown in FIGS. 17C and 17D deforms. FIGS. 18E and 18F are diagrams showing how the structure of Modification 1-3 shown in FIGS. 17E and 17F deforms. FIG. 19A is a perspective view showing a structure 10 corresponding to Modification 1-2. FIG. 19B is a plan view and a side view of the structure 10 shown in FIG. 19A. FIG. 19C is an enlarged view of region A shown in FIG. 19B. FIG. 20 shows how the structure 10 shown in FIG. 19 is bent and deformed. FIG. 21 is a plan view showing a structure 10 according to Modification 1-4. FIG. 22A is a bottom view (viewed from the opposite side of the adsorption surface) of an electrode member 20 according to a modification. FIG. 22B is a side view seen from the direction of arrow B shown in FIG. 22A. Fig. 22C is a side view seen from the direction of arrow C shown in Fig. 22A. Fig. 22D is a perspective view of an electrode member according to a modified example.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The various features shown in the following embodiments can be combined with each other. Furthermore, each feature can be an independent invention. Note that the dimensions shown in the drawings are merely examples of embodiments and modifications, and are not limited to those dimensions.

[0010] 1. Description of the Configuration of the Embodiment The electrostatic attraction device 100 according to the embodiment shown in FIGS. 1A and 1B is configured to electrostatically attract an object to be attracted. In particular, the electrostatic attraction device 100 is suitable for electrostatically attracting an object having a curved surface. The object to be attracted is, for example, a wafer or a film. In the embodiment, the object to be attracted is described as being a wafer or a film, but the present invention is not limited thereto, and the device may be used to attract other objects having a curved surface.

[0011] There are various types of electrostatic chucks (electrostatic adsorption devices), such as Coulomb type, Johnsen-Rahbek type, and gradient type, and the electrostatic adsorption device 100 according to the embodiment can be applied to, for example, these types.

[0012] The X, Y, and Z directions shown in each figure are perpendicular to one another. The X direction is an example of a first direction, and the Y direction is an example of a second direction intersecting the first direction. The X and Y directions are parallel to a plane perpendicular to the thickness direction of the structure 10 of the electrostatic adsorption device 100 according to the embodiment. The Z direction is the thickness direction of the structure 10.

[0013] 1-1. Structure 10 The structure 10 is made of a resin material or a metal material. The resin material preferably has appropriate elasticity and can ensure insulation of the electrode member 20 (described later). Examples of resin materials that can be used include polyurethane resin, polyamide resin, polyimide resin, and acrylate resin. Examples of metal materials that can be used include stainless steel. Different materials may be used depending on the location of the structure 10. For example, the first plate-shaped portion 2A (described later) may be made of polyurethane resin to provide relatively high elasticity, and the second plate-shaped portion 2B (described later) may be made of polyamide resin, polyimide resin, or acrylate resin to provide relatively low elasticity. When the structure 10 is made of a conductive material, insulation may be ensured by, for example, providing an insulating film on the structure 10 or providing an insulating film on the electrode member 20 itself.

[0014] In the embodiment, the overall shape of the region in which the storage section 1 is formed of the structure 10 is a rhombus, but this is not limited to this. For example, it may be a polygonal shape other than a rhombus. The dimensional ratios in the X and Y directions are arbitrary. The structure 10 can be manufactured using, for example, a 3D printer, but is not limited to this method.

[0015] 4A and 4B, the structure 10 includes a plurality of storage sections 1. Each storage section 1 has a gap 1A and a partition wall 1B. An electrode member 20 is stored in the gap 1A. The partition wall 1B partitions adjacent gap sections 1A.

[0016] 1, 4A, and 4B, the partition wall 1B is provided so as to surround the lateral side surface of the electrode member 20. This makes it possible to prevent contact between adjacent electrode members 20 and to insulate the electrode members 20 from each other. Note that the partition wall 1B does not necessarily have to cover the entire lateral side surface of the electrode member 20.

[0017] The gap 1A is configured as a space capable of accommodating the electrode members 20. As shown in FIG. 4C , in one embodiment, the gap 1A has a diamond-shaped planar shape. The space of the gap 1A is divided by a third plate-shaped portion 2C, which will be described later. Two electrode members 20 can be inserted into the gap 1A. In the embodiment, the space of the gap 1A is divided into two by the third plate-shaped portion 2C, but it may be divided into three or more. In other words, not limited to two, but three or more electrode members 20 may be inserted into the gap 1A. Alternatively, the space of the gap 1A may not be divided, and one electrode member 20 may be inserted therein.

[0018] The plurality of gaps 1A are arranged so as to be aligned in a plane. Specifically, the plurality of gaps 1A are arranged so as to be aligned in the X direction, and the plurality of gaps 1A are also arranged so as to be aligned in the Y direction. In this manner, the X direction and the Y direction are directions in which the electrode members 20 and the gaps 1A (accommodating portions 1) are aligned. In the embodiment, the directions in which the electrode members 20 and the gaps 1A (accommodating portions 1) are aligned (i.e., the X direction and the Y direction) are described as being orthogonal (forming an angle of 90 degrees), but this is not limited thereto and they may intersect.

[0019] In this way, the structure 10 can accommodate a plurality of electrode members 20 (36 in one embodiment) arranged in a planar manner. In other words, the structure 10 has gaps 1A arranged two-dimensionally, and as a result, the structure 10 can accommodate a plurality of electrode members 20 arranged two-dimensionally. Note that it is not essential that the gaps 1A are arranged two-dimensionally in the structure 10; they may be arranged one-dimensionally (for example, linearly). For example, the gaps 1A may be arranged only on the line L shown in FIG. 2A .

[0020] The accommodation unit 1 is configured so that the suction surface 20A1 of the electrode member 20 is exposed. That is, as shown in Fig. 1B and Fig. 2A, the structure 10 is open at the top (the suction surface side of the structure 10), and the suction surface 20A1 of the electrode member 20 is exposed.

[0021] 1-1-2. Plate-shaped portion 2 The structure 10 includes a plate-shaped portion 2. The plate-shaped portion 2 has a function of insulating adjacent electrode members 20 from each other, as well as a function of transmitting stress applied to the structure 10 (stress that bends the structure 10) to each part of the structure 10.

[0022] As shown in Figures 3A and 3B, the plate-shaped portion 2 has a plurality of first plate-shaped portions 2A, a plurality of second plate-shaped portions 2B, and a plurality of third plate-shaped portions 2C. The surfaces of the first to third plate-shaped portions 2A to 2C form the partition wall 1B of the storage portion 1 described above. In the embodiment, the plate-shaped portion 2 (first to third plate-shaped portions 2A to 2C) and the force application portion 3 described below, which are components of the structure 10, are described as being integrally molded, but this is not limited to this. The components of the structure 10 may each be composed of independent members (separate members), and the structure 10 may be formed by assembling these members.

[0023] 1-1-2-1. First Plate-Shaped Portion 2A The multiple first plate-shaped portions 2A are provided at intervals from one another. In the embodiment, the multiple first plate-shaped portions 2A are arranged so as to be aligned in the Y direction. When the structure 10 is viewed from above (when the structure 10 is viewed from the same direction as in FIG. 2A ), the first plate-shaped portions 2A are configured in a wavy shape. The first plate-shaped portions 2A are configured by alternatingly connecting inclined portions 2A1 and protruding portions 2A2. The first plate-shaped portions 2A are provided so as to extend in the X direction. The first plate-shaped portions 2A are arranged so as to be aligned independently in the Y direction. In other words, the first plate-shaped portions 2A are not directly connected to one another.

[0024] As shown in FIG. 4C , the inclined portion 2A1 is preferably configured to have a predetermined inclination angle θ with respect to the X direction. Specifically, the predetermined inclination angle θ may be, for example, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, or 75 degrees, or may be within the range of the two values ​​exemplified here. When the inclination angle θ is closer to 45 degrees, the efficiency of bending deformation in the Y direction increases. Therefore, the inclination angle θ is more preferably equal to or greater than 35 degrees and equal to or less than 55 degrees. The inclination angle θ may be different for each inclined portion 2A1, or may vary within a single inclined portion 2A1. In this case, the inclination angle θ may be one of the values ​​listed above or may be within the range of the two values ​​listed above.

[0025] The protruding portion 2A2 is provided to connect the pair of inclined portions 2A1, and in one embodiment, has a flat or substantially flat shape. The protruding portion 2A2 corresponds to a peak (top) or a valley (bottom) of the first plate-shaped portion 2A.

[0026] In the embodiment, the second plate-shaped portion 2B is a flat plate, but the second plate-shaped portion 2B may also be configured in a wavy shape. It is preferable that at least one of the first plate-shaped portion 2A and the second plate-shaped portion 2B is configured in a wavy shape when the structure 10 is viewed from above. In Modification 1-4 (see FIG. 21 ), which will be described later, both portions are configured in a wavy shape.

[0027] The width of the first plate-shaped portion 2A in the Z direction is larger than the width of the second plate-shaped portion 2B in the Z direction. In other words, as shown in Figures 4B and 4C, the position of the end surface 2B1 of the second plate-shaped portion 2B is lower than the position of the end surface 2A3 of the first plate-shaped portion 2A. This makes it possible to prevent the electrode members 20 from coming into contact with each other even if the entire electrostatic adsorption device 100 is curved and deformed, reducing the distance between the electrode members 20.

[0028] 1-1-2-2. Second Plate-Shaped Portion 2B The second plate-shaped portion 2B has the function of transmitting a force (stress that bends the structure 10) applied to the force application portion 3, which will be described later, to the adjacent first plate-shaped portion 2A. The second plate-shaped portion 2B also has the function of restraining the deformation pattern of the first plate-shaped portion 2A. As shown in FIG. 3A, the multiple second plate-shaped portions 2B are provided at intervals from each other. The second plate-shaped portion 2B is also connected to a pair of adjacent first plate-shaped portions 2A. The second plate-shaped portion 2B is provided to extend in the Y direction.

[0029] The second plate-shaped portion 2B has one end in the Y direction connected to one of the first plate-shaped portions 2A, and the other end in the Y direction connected to the other first plate-shaped portion 2A. Specifically, one end of the second plate-shaped portion 2B is connected to a protruding portion 2A2 corresponding to a peak of one of the first plate-shaped portions 2A. The other end of the second plate-shaped portion 2B is connected to a protruding portion 2A2 corresponding to a valley of the other first plate-shaped portion 2A. Note that the second plate-shaped portion 2B does not have to be connected to the first plate-shaped portion 2A at an end.

[0030] The second plate-shaped portions 2B are arranged side by side in the X direction and also side by side in the Y direction. Specifically, as shown in Fig. 3A, the arrangement (positional relationship) of the second plate-shaped portions 2B in any row and the second plate-shaped portions 2B in the row adjacent to that row in the Y direction is staggered. In other words, the second plate-shaped portions 2B adjacent to each other in the Y direction are not arranged side by side in the Y direction, but are arranged at positions offset in the X direction.

[0031] Furthermore, the elasticity of the first plate-shaped portion 2A and the elasticity of the second plate-shaped portion 2B are different. In this embodiment, the entire plate-shaped portion 2 is made of the same material, so the elasticity of the first plate-shaped portion 2A and the elasticity of the second plate-shaped portion 2B can be made different depending on factors such as the thickness, length, and shape of the constituent members. The elasticity may also be made different by changing the material. In this embodiment, the thickness (width in the Y direction) of the first plate-shaped portion 2A is thinner than the thickness (width in the X direction) of the second plate-shaped portion 2B, and the first plate-shaped portion 2A has a wavy shape. Therefore, the elasticity of the first plate-shaped portion 2A is greater than the elasticity of the second plate-shaped portion 2B.

[0032] The first plate-shaped portion 2A described above is a corrugated plate material and has relatively high elasticity due to its shape. In contrast, the second plate-shaped portion 2B is not corrugated and has relatively lower elasticity than the first plate-shaped portion 2A. For this reason, the first plate-shaped portion 2A may be referred to as a high-elasticity portion, and the second plate-shaped portion 2B may be referred to as a low-elasticity portion. Alternatively, the first plate-shaped portion 2A may be referred to as a high-elasticity rod, and the second plate-shaped portion 2B may be referred to as a low-elasticity rod. Furthermore, when the structure 10 is an auxetic structure described below, the first plate-shaped portion 2A may also be referred to as a chevron-shaped element.

[0033] 1-1-2-3. Third Plate Portion 2C The third plate portion 2C shown in FIG. 3B functions to insulate two electrode members 20 aligned in the Y direction. Multiple third plate portions 2C are aligned in the X direction and also aligned in the Y direction. As shown in FIGS. 4A to 4C, the third plate portion 2C is connected to the second plate portion 2B. In this embodiment, the second plate portion 2B and the third plate portion 2C are configured in a cross shape when viewed in a plane. That is, the second plate portion 2B and the third plate portion 2C are connected orthogonally (connected at a 90-degree angle). Note that the connection angle is not limited to this and may be an angle other than 90 degrees. The width of the third plate portion 2C in the Z direction is greater than the width of the second plate portion 2B in the Z direction. 4B and 4C , the position of the end face 2B1 of the second plate-shaped portion 2B is lower than the position of the end face 2C1 of the third plate-shaped portion 2C. This makes it possible to prevent the electrode members 20 from coming into contact with each other even if the entire electrostatic adsorption device 100 is curved and deformed, reducing the distance between the electrode members 20.

[0034] 1-1-3. Force application unit 3 The structure 10 further includes a force application unit 3. The force application unit 3 is configured to be connectable to a stress generation mechanism 30 (driving means) that applies stress to deform the structure 10. The configuration of the stress generation mechanism is not particularly limited, and various configurations such as a robot arm can be adopted, for example. The force application unit 3 functions as a handle that can be grasped by a stress generation mechanism such as a robot arm.

[0035] In the embodiment, the force application unit 3 is provided on an edge portion of the structure 10. The force application unit 3 is connected to the first plate-shaped portion 2A. In one embodiment, the force application unit 3 is connected to the central first plate-shaped portion 2A (two) among the multiple first plate-shaped portions 2A aligned in the Y direction. The stress applied to the force application unit 3 is transmitted to this central first plate-shaped portion 2A and then sequentially transmitted to the first plate-shaped portion 2A adjacent to the central first plate-shaped portion 2A via the second plate-shaped portion 2B connected to this first plate-shaped portion 2A. As a result, the stress that bends the structure 10 is transmitted throughout the structure, causing the structure 10 to deform (bend). The stress applied to the force application unit 3 is, for example, a bending stress that bends the electrostatic adsorption device 100 (structure 10).

[0036] 1-1-4. Curved Portion 10a The structure 10 is configured so that a curved portion 10a can be formed by deformation of at least a portion of the structure 10. The curved portion 10a is a portion that bends when a stress that deforms the structure 10 is applied to the structure 10 via the force application unit 3, as shown in, for example, FIGS. 13A to 13F . In one embodiment, the entire structure 10 is the curved portion 10a, but this is not limited to this. That is, in a state in which stress is applied to the structure 10 via the force application unit 3, the structure 10 may simultaneously have the curved portion 10a and portions where the structure 10 is not curved (flat portions). In other words, the structure 10 may be configured so that both the curved portion 10a and flat portions can coexist. Such a coexistence configuration can be achieved, for example, by varying the material and shape of the structure 10 depending on the location. That is, it may be achieved by configuring a portion of the structure 10 from a flexible material and shape that easily bends, and configuring other portions from a hard material and shape that does not easily bend.

[0037] In this embodiment, the curved portion 10a is curved from one side to the other in the X direction, and is curved from one side to the other in the Y direction.

[0038] The structure 10 is configured so that bending in the X direction and bending in the Y direction occur simultaneously. In other words, when stress is applied to the force application portion 3 of the structure 10, not only bending in the X direction caused by the first plate-shaped portion 2A but also bending in the Y direction caused by the second plate-shaped portion 2B occurs simultaneously in the structure 10, forming a curved portion 10a. In other words, the structure 10 is configured so that bending occurs simultaneously in multiple directions (in this embodiment, two directions, the X direction and the Y direction).

[0039] Specifically, the stress of the force application unit 3 is propagated to the first plate-shaped portion 2A connected to the force application unit 3, causing the first plate-shaped portion 2A to deform so as to be curved from one side to the other in the X direction (an example of a first direction). The curvature direction at this time may be the +Z direction or the −Z direction. When the curvature direction is the +Z direction, it can be said that the structure 10 (electrostatic adsorption device 100) is curved so as to form a convex shape, and when the curvature direction is the −Z direction, it can be said that the structure 10 (electrostatic adsorption device 100) is curved so as to form a concave shape.

[0040] When the first plate-shaped portion 2A bends from one side to the other in the X direction (an example of a first direction), the wavy first plate-shaped portion 2A deforms, reducing the distance between the peaks and valleys in the Y direction, as shown in FIGS. 8A and 8B . In other words, the first plate-shaped portion 2A changes from a wavy shape to a slightly flat plate shape. As a result, the second plate-shaped portion 2B connected to the first plate-shaped portion 2A receives stress from the first plate-shaped portion 2A and moves due to the deformation of the first plate-shaped portion 2A. Because this second plate-shaped portion 2B is also connected to the other first plate-shaped portion 2A, the stress is transmitted to the other first plate-shaped portion 2A. This process is repeated sequentially, and the stress of the force application portion 3 is transmitted to all first plate-shaped portions 2A and second plate-shaped portions 2B arranged in the Y direction. As a result, the structure 10 also bends from one side to the other in the Y direction.

[0041] Furthermore, in the electrostatic attraction device 100, interference between the various components is suppressed when the structure 10 is bent, enabling a smooth transition between a flat state and a curved state. This will be described below. When the first plate-shaped portion 2A is bent from one side to the other in the X direction (an example of a first direction), the distance between the opposing protrusions 2A2 changes, and the size of the gap 1C changes accordingly, as shown in FIGS. 8A and 8B . In the example shown in FIGS. 8A and 8B , the structure 10 is curved to form a concave shape. Therefore, on the attraction surface side of the electrostatic attraction device 100, the distance between the opposing protrusions 2A2 is narrower than in the state before bending. In other words, the gap 1C is smaller on the attraction surface side of the electrostatic attraction device 100. Conversely, as shown in FIG. 8C , the distance between the opposing protrusions 2A2 on the side opposite the attraction surface side of the electrostatic attraction device 100 is wider than in the state before bending. In other words, the gap 1C is larger on the side opposite the attraction surface side of the electrostatic attraction device 100. Although the above description is given for the case where structure 10 is curved concavely, the opposite movement occurs when structure 10 is curved convexly. Thus, structure 10 is configured so that, when transitioning from a flat state to a curved state, the size of the portion of gap 1C on the adsorption surface side and the size of the portion of gap 1C opposite the adsorption surface side are inversely related. This avoids interference between the various portions, and allows for a smooth transition from the flat state to the curved state.

[0042] The positions of the electrode members 20 when the structure 10 (electrostatic attraction device 100) is curved to form a convex or concave shape will be described. As will be described later, each electrode member 20 has an attraction surface 20A1 to which an object to be attracted is attracted. When the structure 10 is in a flat state, each attraction surface 20A1 is disposed parallel to the X-Y plane. On the other hand, when the structure 10 is in a curved state, the position of each attraction surface 20A1 moves to a position corresponding to the imaginary plane Sr shown in FIG. 7. The position of each attraction surface 20A1 when the curved portion 10a is formed will be described with reference to FIG. 7.

[0043] 7, positions P1 and P2 correspond to the positions of the suction surface 20A1 in a planar state. Positions P1 and P2 are reference positions on the suction surface 20A1, e.g., the center of gravity, and can be determined by any method. Position P1 is a position of the suction surface 20A1 closer to the periphery of the structure 10, and position P2 is a position of the suction surface 20A1 closer to the center of the structure 10.

[0044] 7, positions T1 and T2 correspond to the positions of the suction surfaces 20A1 in the curved state. Here, positions T1 and T2 are located on a virtual plane Sr. In this embodiment, the virtual plane Sr corresponds to a portion of the surface of a sphere of any radius. In other words, the virtual plane Sr has a dome shape. While the movement of the positions of two suction surfaces 20A1 is described here, the other suction surfaces 20A1 are also located on the virtual plane Sr in the curved state.

[0045] The imaginary surface Sr can include, for example, a double curved surface or a single curved surface. A double curved surface corresponds to, for example, a spherical surface, an ellipsoidal spherical surface, etc. A single curved surface corresponds to, for example, a cylindrical surface, etc. The imaginary surface Sr in the structure 10 is not limited to a spherical surface, an ellipsoidal spherical surface, or a cylindrical surface, and may be any other complex curved surface. That is, although the embodiment has been described assuming that the imaginary surface Sr is a sphere (a part of the surface of a sphere), the present invention is not limited thereto, and if the curvature of the structure 10 is complex, the imaginary surface Sr will be a complex curved surface corresponding to that.

[0046] In this manner, when the curved portion 10a is formed on the structure 10, the attraction surfaces 20A1 of the plurality of electrode members 20 are positioned at positions corresponding to the curvature of the curved portion 10a (in one embodiment, at positions T1 and T2 on the imaginary plane Sr). This allows the curvature of the structure 10 to be adjusted to match the curvature of the object to be attracted, and the attraction surfaces 20A1 can be positioned along the curved surface of the object to be attracted. In other words, the attraction surfaces 20A1 of the electrode members 20 of the electrostatic attraction device 100 can be positioned along the curved surface of the object to be attracted, corresponding to the curvature of the curved portion 10a, thereby improving the curved surface adaptability. The curved surface adaptability refers to the ability to easily move the position of the attraction surfaces 20A1 to a position along the curved surface of the object to be attracted.

[0047] An example of a structure that simultaneously generates curvature in the X direction and curvature in the Y direction in the structure 10 is an auxetic structure (expanded auxetic structure). For this reason, the structure 10 can be configured with an auxetic structure (expanded auxetic structure). The auxetic structure (expanded auxetic structure) will be described in detail later in "2. Auxetic structure (expanded auxetic structure)".

[0048] 1A and 1B, the electrode member 20 is configured to be insertable into the structure 10. When the electrode member 20 is inserted into the structure 10, the electrode member 20 engages with the structure 10, and the electrode member 20 is held by the structure 10.

[0049] The electrode member 20 is provided so that at least a portion thereof is covered by the structure 10. In other words, the electrode member 20 is provided so that at least a portion thereof is surrounded by the structure 10. That is, the arrangement of the electrode member 20 in the Z direction coincides with that of the structure 10. In other words, the electrode member 20 is not arranged so as to protrude from the structure 10 in the Z direction, but is arranged at the same position or approximately the same position. This makes it possible to prevent the electrostatic adsorption device 100 from becoming large. Note that the portion of the electrode member 20 that is covered (surrounded) by the structure 10 may or may not be in contact with the structure 10.

[0050] When the curved portion 10a is formed in the structure 10 (when the structure 10 is curved), the electrode member 20 moves accordingly, and the attraction surface 20A1 of the electrode member 20 is positioned at a position corresponding to the curvature of the curved portion 10a. As a result, the attraction surface 20A1 of the electrode member 20 can be positioned at a position along the curved surface of the object to be attracted that corresponds to the curvature of the curved portion 10a. In other words, the curvature and radius of the curvature of the structure 10 itself are more likely to match the curvature and radius of the virtual surface Sr, making it easier to position the attraction surface 20A1 at a position along the curved surface of the object to be attracted. This improves the curved surface adaptability of the electrostatic attraction device 100 according to this embodiment to the curved surface of the object to be attracted.

[0051] As shown in FIGS. 6A to 6D , the electrode member 20 includes a base 20A and an insertion portion 20B. As shown in FIG. 5B , the base 20A is disposed on the second plate-shaped portion 2B when the electrode member 20 is inserted into the structure 10. The base 20A has an attraction surface 20A1 for electrostatically attracting an object to be attracted. In the embodiment, the attraction surface 20A1 is configured as a flat surface, but is not limited thereto. It may be configured as a curved surface, may have multiple concaves and convexes, or may have a mixed configuration of flat and curved surfaces. Both the base 20A and the insertion portion 20B are housed in the housing 1. In the embodiment, the electrode member 20 is held in the housing 1 by frictional force between the electrode member 20 and the surface of the structure 10. Here, the electrode member 20 has multiple (two in the embodiment) insertion portions 20B. This increases the surface area of ​​the electrode member 20, making it easier for the electrode member 20 to be held in the housing 1. The insertion portion 20B is inserted into a substantially triangular space formed by the first plate portion 2A, the second plate portion 2B, and the third plate portion 2C. A gap 20C is formed between the pair of insertion portions 20B. When the electrode member 20 is housed in the housing portion 1, the second plate portion 2B is disposed in the gap 20C.

[0052] In this embodiment, the diamond-shaped gap 1A of the structure 10 is divided by the third plate-shaped portion 2C. A pair of electrode members 20 are arranged symmetrically with respect to the third plate-shaped portion 2C in the space of the divided gap 1A. A positive voltage and a negative voltage are applied to the pair of electrode members 20 via a voltage application device 50 (see FIG. 16B ) having a power supply. This enables the electrostatic attraction device 100 to attract an object to be attracted. Note that one electrode member 20 may be assembled in the diamond-shaped gap 1A of the structure 10, and the voltages applied to adjacent electrode members 20 may be different, either positive or negative. Furthermore, the number of electrode members 20 assembled in the diamond-shaped gap 1A of the structure 10 may be more than two.

[0053] The attraction surface 20A1 of the electrode member 20 is preferably bipolar. The electrode member 20 is preferably composed of a positive electrode, a negative electrode, and an insulating region therebetween. The insulating region is a component of the electrode member 20 that insulates the positive electrode and negative electrode of the electrode member 20. When the attraction surface 20A1 is bipolar, there is no need to connect or arrange an electrode on the attraction target side, and the attraction target can be transported by attraction from one side.

[0054] In order to make the attracting surface 20A1 bipolar, it is preferable to uniformly disperse the positive and negative electrodes on the attracting surface 20A1. Alternatively, one electrode member 20 may be configured to include both the positive and negative electrodes.

[0055] The material constituting the electrode member 20 may be, for example, a metal such as stainless steel or aluminum, or a semiconductor such as a doped Si wafer. The material (insulating material) constituting the insulating region of the electrode member 20 may be, for example, polyamide, polyimide, acrylate, or the like. The electrode member 20 may be manufactured by any method, and known techniques may be used, such as a 3D printer or a water jet method.

[0056] In the electrostatic attraction device 100, at least one of the attracting surface 20A1 side and the opposite side of the electrode member 20 may be covered with an insulator (insulating layer). When an insulating layer is provided on the attracting surface 20A1 side of the electrode member 20, if the insulating layer is elastically deformable or soft, the flexibility of the insulating layer on the attracting surface 20A1 also enables the electrode member 20 to adapt to the surface shape, such as a curved surface, of the object to be attracted. This also prevents the electrode member 20 inserted into the structure 10 from falling off.

[0057] The dimensions of the attraction surface 20A1 of the electrode member 20 in the X and Y directions can be various, for example, 10 μm to 10 cm, 10 μm to 1000 μm, 1 to 10 mm, 1 to 10 cm, 10 cm or more, etc. Furthermore, the dimensions in the X direction and the Y direction may be different.

[0058] 6A and 6D, the electrode member 20 has a top portion 20a. The top portion 20a is not sharp like the apex of a triangle, but has, for example, a flat surface. This makes it possible for the electrode member 20 to suppress the deformation of the first plate-shaped portion 2A.

[0059] 2. Auxetic Structure 2-1. Poisson's Ratio of Structure 10 Incidentally, a structure called an auxetic structure is known. Note that the structure 10 according to the embodiment does not necessarily have to be identical to an auxetic structure, but it is preferable to use an auxetic structure to adsorb a curved wafer or film. Here, an auxetic structure will be described in detail as an example of the configuration of the structure 10.

[0060] In the following description, in one embodiment, the tensile direction is the X direction. The term "Poisson's ratio" is also used in the following description. This Poisson's ratio corresponds to the ratio of the amount of deformation in the longitudinal direction (tensile direction) of a material to the amount of deformation in the lateral direction (direction perpendicular to the tensile direction) when a load is applied to the material.

[0061] If the structure 10 is an auxetic structure, the structure 10 is defined as having a negative or zero Poisson's ratio such that the dimension perpendicular to the tensile direction is elongated or constant, and the electrode member 20 will be supported by the structure 10 having such a Poisson's ratio.

[0062] It should be noted that in the embodiment, the Poisson's ratio is extended and applied to the electrostatic attraction device 100 (structure 10). In other words, the Poisson's ratio of the electrostatic attraction device 100 (structure 10) can be defined as the amount of change in width of the electrostatic attraction device 100 (structure 10) in the X direction and the amount of change in width of the electrostatic attraction device 100 (structure 10) in the Y direction. More specifically, in the embodiment, the Poisson's ratio of the auxetic structure (structure 10) is used for deformation based on the geometric pattern (arrangement) of the structure 10, rather than deformation based on the material composition of the structure 10. The auxetic structure can be regarded as a structure including a skeletal portion forming a geometric pattern (arrangement) and patterned spaces formed between the skeletal portions. The skeletal portion has a portion that bends and deforms like a hinge. The auxetic structure utilizes its property of deforming into a dome shape when subjected to bending stress.

[0063] In general, the auxetic structure has a negative Poisson's ratio. Here, the case where the Poisson's ratio is 0 is also included. Therefore, the auxetic structure may be defined as an extended auxetic structure so that the auxetic structure having a Poisson's ratio of 0 can also be included.

[0064] 2-2. Explanation of Poisson's Ratio Here, the relationship between Poisson's ratio and deformation due to tensile stress will be briefly explained with reference to FIGS. 9A to 9C. In FIGS. 9A to 9C, the shape before application of tensile stress is represented by a solid line, and the shape after application of tensile stress is represented by a dashed line. In a material or structure with a typical positive Poisson's ratio shown in FIG. 9A, shape 1-2 after application of tensile stress to shape 1-1 before application of tensile stress is compressed in a direction perpendicular to the tensile direction. When the Poisson's ratio shown in FIG. 9B is negative, shape 2-2 after application of tensile stress to shape 2-1 before application of tensile stress expands in a direction perpendicular to the tensile direction. When the Poisson's ratio shown in FIG. 9C is zero, shape 3-2 after application of tensile stress to shape 3-1 before application of tensile stress remains constant in the direction perpendicular to the tensile direction. In Figures 9B and 9C, the dimensions are elongated or constant in both directions perpendicular to the tensile direction, but the dimensions may be elongated or constant in only one direction perpendicular to the tensile direction.

[0065] 2-3. Chevron-Shaped Element (First Plate-Shaped Portion 2A) As shown in FIGS. 10A and 10B , the wavy first plate-shaped portion 2A described above corresponds to a chevron-shaped element in an auxetic structure. The chevron-shaped elements are longitudinally aligned in the X direction, with multiple chevron-shaped elements arranged parallel to the Y direction. An electrode member 20 is inserted between adjacent chevron-shaped elements. As shown in FIGS. 10C and 10D , the chevron-shaped elements are deformed by tensile stress (load) in the X direction to reduce the wave height of the chevron shape (deformed to reduce the width in the Y direction), and are extended in the X direction. As a result, the bending angle of the chevron-shaped elements increases from approximately 90° to an obtuse angle. At this time, the entire electrostatic adsorption device 100 (structure 10) also increases in the Y direction. That is, it also increases in the direction perpendicular to the tensile direction.

[0066] FIG. 10E illustrates the electrostatic adsorption device 100 when a bending stress is applied to the structure 10, causing the adsorption surface side to bend concavely. As shown in FIG. 10E, the bending stress is preferably applied so that the inside dimension of the peripheral edge fr (see also FIG. 1B ) on the adsorption surface side of the structure 10 is constant. The inside dimension corresponds to the curve along the imaginary surface Sr of the curved portion 10a or the peripheral edge fr shown in FIG. 10E . When such a bending stress is applied, the dimensions of the concave curved surface (double curved surface) inside the peripheral edge fr on the adsorption surface side become constant or shorten. Here, the concave curved surface (double curved surface) corresponds to the imaginary surface Sr described above. However, even if the dimension is shortened, the shortened width is kept very small. This is because, when the structure 10 is curved concavely, the portion of the first plate-shaped portion 2A serving as a chevron-shaped element on the adsorption surface side tends to contract, but this contraction is hindered by interference between the first plate-shaped portion 2A and the electrode member 20. Additionally, the contraction of the first plate-shaped portion 2A is also suppressed by the second plate-shaped portion 2B serving as a low-elasticity portion. In this way, the dimensions of the concave curved surface are kept constant or are prevented from shortening, so the area of ​​the concave curved surface also remains constant or is prevented from shrinking. This prevents wrinkles from forming on the object to be adsorbed. The fact that the portion of the structure 10 on the adsorption surface side is less likely to contract corresponds to the position of the neutral surface (the surface that does not expand or contract) of the structure 10 shifting closer to the adsorption surface when the structure 10 is bent.

[0067] The above describes an example in which the structure 10 is deformed when curved to form a concave shape. When the structure 10 is curved to form a convex shape, the planar diamond-shaped imaginary surface Sr of the structure 10 deforms to form a convex curved surface (see, for example, the imaginary surface Sr in FIG. 7 ). The area of ​​the convex curved surface is larger than the planar diamond-shaped imaginary surface Sr before deformation. The increased area of ​​the convex curved surface allows for more reliable adsorption of the electrostatically adsorbed object (e.g., a film). In other words, when the electrostatic adsorption device 100 is adsorbed to an object in a flat state and then transitions to a curved state, the area increases from the flat state to the curved state. This applies stress to the surface of the object to be adsorbed, thereby advantageously preventing wrinkles from forming on the object to be adsorbed. Note that while the advantages of a constant or expanding area are mentioned here, the embodiments do not exclude a form in which the area decreases.

[0068] The structure 10 is composed of a first plate-shaped portion 2A having a relatively high elasticity and a second plate-shaped portion 2B having a relatively low elasticity. When the structure 10 is an auxetic structure, the structure consisting of the first plate-shaped portion 2A and the second plate-shaped portion 2B can be defined as a reentrant honeycomb structure.

[0069] Varying the inclination angle θ of the inclined portion 2A1 of the chevron-shaped element allows for adjustment of the magnitude of extension and bending in the Y direction when tension (stretching) in the X direction is transmitted in the Y direction. A smaller inclination angle θ allows for a greater degree of extension in the Y direction relative to tension (stretching) in the X direction, so the shape of the double curved surface can be deformed by changing the inclination angle θ. The shape of the imaginary surface Sr can also be changed by changing the spacing between the chevron-shaped elements, i.e., the length of the second plate-shaped portion 2B.

[0070] 2-4. Properties of the Auxetic Structure According to the Embodiment 2-4-1. Deformation due to Application of Tensile Stress in the X Direction Figures 11A to 11C show the change in shape when the tensile stress (no bending stress) in the X direction is changed in the structure 10. The structure 10 as an auxetic structure is configured so that the width in the Y direction increases when tensile stress is applied in the X direction. This will be explained below. The first plate-shaped portion 2A is also called a chevron-shaped element.

[0071] When a tensile stress is applied in the X direction, the chevron-shaped elements (first plate-shaped portion 2A), which are two elastic elements connected to the force application portion 3, deform so as to elongate in the X direction. This elongation of the chevron-shaped elements in the X direction is an elastic deformation of the chevron-shaped elements, such that the wave height of the chevron-shaped elements decreases. In other words, this elongation is a shape change in which the peaks and valleys of the chevron-shaped elements act as hinges, widening the angle formed by the peaks and valleys. In reality, this elongation is not an elastic elongation of the material of the chevron-shaped elements themselves. The elongation of the chevron-shaped element in the center in the Y direction is transmitted via the second plate-shaped portion 2B to the adjacent chevron-shaped elements, and these chevron-shaped elements also elongate in the X direction.

[0072] 3A, the two chevron-shaped elements (first plate-shaped portion 2A) connected to the force application portion 3 are referred to as the first high-elasticity rod R1, the next high-elasticity rod as the second high-elasticity rod R2, and further in order as the third high-elasticity rod R3, fourth high-elasticity rod R4, and fifth high-elasticity rod R5. Also, as shown in FIG. 3B, the low-elasticity rods (second plate-shaped portion 2B) connected to the inside of each high-elasticity rod are referred to as the first low-elasticity rod r1 to fifth low-elasticity rod r5, respectively.

[0073] At this time, when tensile stress is applied from the force application unit 3 to the two upper and lower first high-elasticity rods R1, both first high-elasticity rods R1 deform and extend so that the wave height decreases (the difference in height between the peaks and valleys decreases). When the two upper and lower first high-elasticity rods R1 extend, the tensile stress is transmitted in the X direction to the upper and lower second high-elasticity rods R2 via the upper and lower second low-elasticity rods r2 (rods that are relatively resistant to dimensional change), causing the upper and lower second high-elasticity rods R2 to also extend. In the same way, the tensile stress in the X direction is transmitted to all of the upper and lower third to fifth high-elasticity rods R3 to R5.

[0074] When tensile stress is applied to the two upper and lower first high-elasticity rods R1, they deform so that the wave height decreases. Here, a first low-elasticity rod r1 (whose dimensions remain unchanged) is interposed between the crest of one first high-elasticity rod R1 and the trough of the other first high-elasticity rod R1. Meanwhile, there is no connection between the trough of one first high-elasticity rod R1 and the crest of the other first high-elasticity rod R1 (i.e., a gap 1C is formed). Therefore, deformation of one and the other first high-elasticity rods R1 occurs so that the interval (distance) between the trough of one first high-elasticity rod R1 and the crest of the other first high-elasticity rod R1 increases. That is, the trough of one first high-elasticity rod R1 moves upward, and the crest of the other first high-elasticity rod R1 moves downward.

[0075] When the valley of one of the first high-elasticity rods R1 moves upward, the second low-elasticity rod r2 also moves upward. When one of the second low-elasticity rods r2 moves upward, the crest of one of the second high-elasticity rods R2 also moves upward. Here, as described above, the second high-elasticity rod R2 also elongates and deforms so that the wave height decreases. Therefore, when the Y-direction position of the crest of one of the second high-elasticity rods R2 is used as a reference, the valley of one of the second high-elasticity rods R2 moves upward. The operation of the other second low-elasticity rod r2 and second high-elasticity rod R2 is symmetrical to that of the one of the second low-elasticity rods r2 and second high-elasticity rod R2 described above, and therefore will not be described here. This action is transmitted sequentially to the third low-elasticity rod r3 to the fifth low-elasticity rod r5 and the third high-elasticity rods R3 to the fifth high-elasticity rods R5 in the same manner as described above. Thus, in the auxetic structure, when a tensile stress is applied to the first high-elasticity rod R1 to stretch it in the X direction, the dimension of the auxetic structure expands in the Y direction (both sides) perpendicular to the tensile direction. The fifth high-elasticity rod R5, located at the apex of the diamond, expands the least. Specifically, the elongation of the elastic rods decreases stepwise (regularly) from the first high-elasticity rod R1 toward the apex of the diamond. Additionally, the degree of expansion of the spacing (distance) between adjacent elastic rods also gradually decreases from the first high-elasticity rod R1 toward the apex of the diamond.

[0076] The auxetic structure (structure 10) described here has a negative Poisson's ratio. Note that the thickness (dimension in the Z direction) of this structure 10 does not change substantially. That is, although structure 10 is described as a two-dimensional auxetic structure, if it is a three-dimensional auxetic structure, dimensional changes in the three dimensions are acceptable.

[0077] 12A to 12F show the change in shape when bending stress (not the tensile stress described in FIGS. 11A to 11C) is applied to the structure 10. When bending stress is applied to the structure 10 as an auxetic structure, the structure 10 is bent so that the diagonal line in the X direction of the diamond shape of the structure 10 becomes convex upward. At the same time, bending also occurs in the direction perpendicular to the X direction of the XY plane (the Y direction), generating a double curved surface in the structure 10. Note that this double curved surface corresponds to a virtual surface Sr that represents the position after the adsorption surface 20A1 of the electrode member 20 has moved when the electrode member 20 is placed on the structure 10.

[0078] The reason why a double curved surface (curved surface) is generated is as follows. The stress generating mechanism 30 generates a convex bend in the structure 10 in the upward direction (+Z direction). At this time, the circumferential dimension of the upper surface (convex surface) of the structure 10 in the Z direction becomes larger than the circumferential dimension of the lower surface (concave surface) in the Z direction. The upper surface (convex surface) corresponds to the surface Rg1 shown in FIG. 2C , and the lower surface (concave surface) corresponds to the surface Rg2 in the same figure. Here, consider a case where a bending stress on the structure 10 causes tensile stress to act on both the upper surface (convex surface) and the lower surface (concave surface) of the structure 10. When the structure 10 has a negative Poisson's ratio, the effect of elongation in the X direction on elongation in the Y direction is greater on the upper surface (convex surface) of the structure 10 than on the lower surface (concave surface). In other words, the elongation of the upper surface (convex surface) of the structure 10 is relatively long, and the elongation of the lower surface (concave surface) of the structure 10 is relatively short. Thus, the difference in elongation in the Y direction between the upper surface (convex surface) and the lower surface (concave surface) generates bending stress in the Y direction, which means that the structure 10 curves from one side to the other in the Y direction.

[0079] Although the above description has been given of the case where both the upper surface (convex surface) and the lower surface (concave surface) are elongated, this is not limiting. Even when the dimensions of the lower surface (concave surface) are constant, or when the dimensions of the lower surface (concave surface) are shortened and compressive stress occurs, bending stress in the Y direction occurs, generating a double curved surface.

[0080] 13A to 13C and 14A to 14F show deformation of the auxetic structure (structure 10) incorporating the electrode members 20. From these figures, it can be seen that the deformation of the structure 10 incorporating the electrode members 20 is similar to the contents described in sections 2-4-1 and 2-4-2.

[0081] 2-4-4. Functions of the Auxetic Structure As described above, when the stress generating mechanism 30 applies a bending stress to the electrostatic adsorption device 100 (structure 10), the electrostatic adsorption device 100 (structure 10) simultaneously bends in the X direction (an example of a first direction) and the Y direction (an example of a second direction), generating a double curved surface. In other words, the structure 10 is configured so that curvature in the X direction and curvature in the Y direction occur simultaneously. The simultaneous curvatures in multiple directions are based on Function 1 and Function 2 below.

[0082] Function 1: When the structure 10 is pulled in a specific direction (X direction), not only does the width of the structure 10 expand in the specific direction, but also in the direction intersecting the specific direction (Y direction). Function 1 is the content described in Section 2-4-1 above. Function 1 is effectively achieved by arranging the second plate-shaped portion 2B at the portion (valley and crest) of the adjacent wavy first plate-shaped portions 2A where the opposing width is widest. Note that the second plate-shaped portion 2B does not need to perfectly match the portion where the opposing width is widest; a slight deviation is acceptable. Function 1 is effectively achieved by the elasticity of the second plate-shaped portion 2B being smaller than that of the first plate-shaped portion 2A. This is because deformation of any first plate-shaped portion 2A is more easily transmitted to the first plate-shaped portion 2A adjacent to that first plate-shaped portion 2A, making it easier to ensure the amount of deformation of the structure 10 in the Y direction.

[0083] Function 2: When a bending stress is applied to the structure 10 so that the structure 10 is convex in the +Z direction, there is a difference between the amount of dimensional change in the Z direction of the upper surface (corresponding to region Rg1 in Figure 2C) and the amount of dimensional change in the Z direction of the lower surface (corresponding to region Rg2 in Figure 2C). In the embodiment, the amount of dimensional change in the upper surface is greater than the amount of dimensional change in the lower surface. Here, when the structure 10 is an auxetic structure, the amount of dimensional change in the Y direction will change depending on the amount of dimensional change in the tensile direction. Because the amount of dimensional change in the upper surface in the tensile direction is large, the amount of dimensional change in the Y direction will be large. Conversely, because the amount of dimensional change in the tensile direction of the lower surface is small, the amount of dimensional change in the Y direction will be small. In this way, a difference in the amount of dimensional change occurs in the Y direction as well, which causes curvature in the Y direction.

[0084] In the description here, functions 1 and 2 are employed to configure the structure 10 so that curvature in the X direction and curvature in the Y direction occur simultaneously, but functions 1 and 2 are not essential, and other functions may also be employed.

[0085] 15 shows the state in which wiring for a voltage application device 50 is applied to the electrode member 20 of an electrostatic attraction device 100 having an auxetic structure. It also shows the state in which a plastic film is electrostatically attracted to the electrostatic attraction device 100 in a flat state, and then the electrostatic attraction device 100 is curved so as to form a double curved surface with an R of 100 (mm).

[0086] 16A and 16B, a description will be given of a calculation formula for generating a double-curved surface while maintaining constant the length of each side of the diamond of the attracting surface when the attracting surface of the electrostatic attracting device 100 shown in Fig. 15 is transformed from a flat surface to a double-curved surface. Note that the attracting surface described in this section 2-5 is a surface corresponding to the virtual surface Sr, and does not refer solely to the attracting surface 20A1 of the electrode member 20.

[0087] In the diamond-shaped attraction surface of Figure 16A, the horizontal (X-direction) length of the attraction surface is defined as h. The vertical (Y-direction) length is defined as w. The output curvature radius is defined as R. The top corner of the diamond is defined as point a, and the right corner of the diamond is defined as point b.

[0088] FIG. 16B is a side view of the electrostatic attraction device 100 when the attraction surface is bent with a curvature radius R. The lower corner of the vertical (Y-direction) diagonal of the diamond of the attraction surface in FIG. 16A is located at the center of the attraction surface in the X-direction in the side view of FIG. 12B. This point is the origin of the XZ coordinate system, with the horizontal direction being the X-axis and the vertical direction being the Y-axis, and the coordinates of this origin are (0, 0). In this case, the coordinates of the corners at both ends of the horizontal (X-direction) diagonal of the diamond can be expressed as (x, 0) and (-x, 0), respectively, in FIG. 16B. When bent with a curvature radius R, the inclination angle of the attraction surface at point b is defined as θ.

[0089] First, from h, w, and R, z is calculated using the following formula: ２ Ask for.

[0090] The desired z ２ From the above, x and θ can be calculated using the following formula.

[0091] The calculated x is the X-direction position of the points at both ends of the diagonal line in the X-direction of the diamond-shaped attracting surface, which is obtained by using the force application unit 3 of the electrostatic attraction device 100 to bend the attracting surface to a curvature radius R. The calculated θ is the inclination angle of the bend at this X-direction position.

[0092] When actually operating the electrostatic attraction device 100, it is advisable to calculate the gradual change of the radius of curvature R from infinity to the target radius of curvature, and drive the electrostatic attraction device 100 in accordance with the obtained values ​​of x and θ. This driving can be performed using, for example, a computer and a robot arm.

[0093] In Figure 15, reflections (cloudiness) can be seen on the film due to light reflection, but when it was flat, it was adsorbed without wrinkles. On the other hand, when it was double-curved, wrinkles were visible on part of the adsorption surface, but it was confirmed that they were slight.

[0094] 3. Description of Various Methods Using the Electrostatic Adsorption Device 100 3-1. Method for Correcting Wafer Warpage In recent years, wafers have become larger and thinner, which can lead to wafer warpage (curvature), for example, during wafer transport. The electrostatic adsorption device 100 is capable of adsorbing such curved wafers while effectively avoiding damage. This makes it possible to transport the wafer without damaging it, and also makes it possible to correct the warpage and return it to a flat state. The application of the wafer is not particularly limited, but the device is suitable for, for example, power semiconductor wafers.

[0095] The method for straightening a wafer warpage according to the embodiment includes a suction step and a warpage straightening step. In the suction step, a wafer is placed on the suction surface 20A1 of the electrode member 20 of the curved structure 10. In the warpage straightening step, the structure 10 is deformed from the curved state to a flat state while the object to be attracted is still being attracted to the suction surface 20A1.

[0096] The curved state described above is, for example, a state in which the structure 10 is curved, as shown in Fig. 8A etc. Note that the structure 10 may be curved to form a convex shape, a concave shape, or a combination of a convex shape and a concave shape.

[0097] In the above-described planar state, for example, as shown in FIG. 1B, the attraction surfaces 20A1 of the plurality of electrode members 20 are aligned at the same height.

[0098] Note that the electrostatic attraction device 100 may be pressed against the wafer, which is the object to be attracted, to additionally deform the shape of the electrostatic attraction device 100 so that the shape of the electrostatic attraction device 100 matches or approaches the surface shape of the wafer. That is, in the attraction step, the object to be attracted may be attracted to the attraction surface 20A1 of the electrode member 20 while the structure 10 is deformed into a curved state.

[0099] The warpage correction method may be performed in a state where the wafer sucked in the suction step is placed on a mounting table. Furthermore, the warpage correction method may be performed by decompressing and sucking the wafer through suction holes formed in the mounting table to prevent the wafer from shifting from the mounting table.

[0100] The height difference between the uppermost and lowermost suction surfaces is preferably 10 cm or less. Here, the uppermost suction surface is the suction surface 20A1 at the highest position in the Z direction among the suction surfaces 20A1 at the curved portion 10 a. The lowermost suction surface is the suction surface 20A1 at the lowest position in the Z direction among the suction surfaces 20A1 at the curved portion 10 a.

[0101] 3-2. Film Mounting Method Displays such as organic EL displays can have curved screens. However, as displays become larger, it becomes difficult to grasp the planar sheet-like member (e.g., a thin-film electronic device) used in the display and attach it evenly to the curved display structure. The electrostatic adsorption device 100 makes it possible to attach the film (sheet-like member) evenly to the curved surface of the display structure while effectively preventing damage to the film (sheet-like member).

[0102] The film attachment method according to the embodiment includes an adsorption process, a deformation process, and an attachment process. In the adsorption process, the film is adsorbed onto the adsorption surface 20A1 of the electrode member 20 of the structure 10. In the deformation process, the structure 10 is curved. The deformation process is performed before, after, or together with the adsorption process. In the attachment process, the film adsorbed to the curved structure 10 is attached to an attachment target. The attachment target is, for example, a structure that constitutes a display such as an organic electroluminescence (EL) display. In the attachment process, the voltage of the voltage application device 50 is controlled so that the film is detached (released) from the adsorption surface of the electrostatic adsorption device 100.

[0103] Furthermore, the area of ​​the imaginary surface Sr associated with the suction surface 20A1 in the curved state is either larger or constant, or even if it shrinks, the amount of shrinkage is kept small compared to the planar area of ​​the suction surface 20A1 in the flat state. This makes it possible to effectively prevent wrinkles from forming in the film. In other words, if the area associated with suction were to shrink significantly, the possibility of wrinkles forming in the film increases. However, when the electrostatic suction device 100 according to the embodiment transitions from the flat state to the curved state, the area of ​​the imaginary surface Sr is either larger or constant, or even if it shrinks, the amount of shrinkage is kept small, making it easier to prevent wrinkles from forming in the film.

[0104] 4. Description of Functions and Effects of the Embodiment In the electrostatic attraction device 100 according to the embodiment, the electrode member 20 is provided so that at least a portion thereof is covered by the structure 10, which is capable of forming the curved portion 10a. Therefore, the electrode member 20 is provided integrally with the structure 10. As a result, when the curved portion 10a is formed in the structure 10, the electrode member 20 moves in response to this, and the attraction surface 20A1 of the electrode member 20 is positioned at a position corresponding to the curvature of the curved portion 10a (see FIG. 7 ). As a result, the attraction surface 20A1 of the electrode member 20 can be positioned along the curved surface of the object to be attracted, corresponding to the curvature of the curved portion 10a, thereby improving adaptability to curved surfaces.

[0105] Furthermore, in the electrostatic chucking device 100 according to the embodiment, the electrode members 20 are provided integrally with the structure 10, which allows for a corresponding reduction in size and thickness.

[0106] 5. Modifications 5-1. Modification 1: Modification of Structure 10 5-1-1. Modification 1-1: Poisson's Ratio is Negative In Modification 1-1 shown in FIGS. 17A and 17B, the structure 10 is composed of an auxetic structure with a negative Poisson's ratio. In the embodiment, as shown in FIG. 4C, the first plate-shaped portion 2A has a flat protrusion 2A2. However, in Modification 1-1, this portion is formed at an acute angle. Even with this configuration, the same effect as the embodiment can be obtained. Note that the angle θ shown in the figure is greater than 0 degrees and less than 90 degrees. As shown in FIGS. 18A and 18B, when tensile stress is applied to the structure 10, the width expands not only in the tensile direction but also in the direction perpendicular thereto.

[0107] 5-1-2. Modification 1-2: Poisson's ratio is zero In modification 1-2 shown in Figures 17C, 17D, and 19A to 19C, the structure 10 is made of an auxetic structure (expanded auxetic structure) having a Poisson's ratio of zero.

[0108] In this structure, the first plate-shaped portions 2A are arranged parallel to the Y direction so that the positions of the peaks and valleys of each first plate-shaped portion 2A coincide with the positions of the peaks and valleys of other first plate-shaped portions 2A in the X direction. This is where Modification 1-2 differs from the embodiment and Modification 1-1. The angle at which the second plate-shaped portion 2B intersects with the first plate-shaped portion 2A is an acute angle θ (0°<θ<90°) and its supplementary angle (180°-θ). Preferably, the angle θ is 30°≦θ≦80°, and more preferably 30°≦θ≦60°.

[0109] When tensile stress is applied to the structure 10 in the X direction, the first plate-shaped portion 2A elongates in the X direction, causing the valleys of the first plate-shaped portion 2A to deform and rise. However, the valleys of adjacent first plate-shaped portions 2A also move and rise in the same manner, so the width of the structure 10 in the Y direction does not increase. In other words, as shown in Figures 18C and 18D, when tensile stress is applied to the structure 10, the width only in the tensile direction increases, while the width in the direction perpendicular thereto remains the same. In the configurations of the embodiment and Modification 1-1, the formed imaginary surface Sr is a double-curved surface (e.g., a sphere), but in the configuration of Modification 1-2, the formed imaginary surface Sr is a single-curved surface (e.g., a cylindrical surface). In other words, in Modification 1-2, the structure 10 is configured to only bend in a specific direction (the X direction).

[0110] 20 shows how the shape of the structure 10 according to Modification 1-2 changes when a bending stress is applied. As shown in FIG. 20, the dimension in the Y direction remains unchanged (constant). In other words, the imaginary surface Sr becomes a single curved surface.

[0111] 5-1-3. Modification 1-3: Positive Poisson's Ratio In modification 1-3 shown in FIGS. 17E and 17F, the structure 10 has a positive Poisson's ratio. This structure 10 has a honeycomb structure. Furthermore, the angle θ between the first plate-shaped portions 2A aligned in the X direction and the second plate-shaped portions 2B aligned in the Y direction satisfies 90°<θ<180°. In this structure, when a tensile stress is applied to the first plate-shaped portions 2A in their longitudinal direction (X direction), the first plate-shaped portions 2A deform so that the distance between them decreases. A configuration such as modification 1-3 may be employed for the structure 10.

[0112] 5-1-4. Variation 1-4: Auxetic Structure Without Reentrant Honeycomb Structure Figure 21 shows another example of an auxetic structure, a structure with a sinusoidal lattice pattern. This structure 10 does not have a reentrant honeycomb structure. Furthermore, this structure 10 does not include a second plate-shaped portion 2B. That is, the structure 10 is composed of a first plate-shaped portion 2A extending in the X direction and a first plate-shaped portion 2A extending in the Y direction. In this structure 10 with a sinusoidal lattice pattern, by changing the location where bending deformation is applied (the location of the handle) and the direction of bending stress, the virtual surface Sr formed can take on a single curved surface or multiple double curved surfaces. In other words, it is possible to generate virtual surfaces Sr of various shapes.

[0113] 5-2. Modification 2: Modification of Electrode Member 20 As shown in Figures 22A to 22D, the electrode member 20 has a slit 20B1 formed by cutting away a portion of the insertion portion 20B. The slit 20B1 is used to insert a terminal for wiring to the electrode member 20 after the electrode member 20 is inserted into the structure 10. In addition, a cut-away portion 20B2 is formed in the insertion portion 20B, reducing the volume of the insertion portion 20B. This allows the electrode member 20 to be made lighter.

[0114] 5-3. Other Forms In the embodiment, a form capable of transitioning between a flat state and a curved state has been described, but the present invention is not limited to this. The electrostatic attraction device 100 may also be in a form in which the curved state is fixed. In this case, the structure 10 has a curved portion 10a. Such an electrostatic attraction device 100 is suitable, for example, when it is desired to specialize in gripping an attraction target having a curved surface of a predetermined shape.

[0115] The structure 10 of the electrostatic attraction device 100 according to the embodiment may be configured to bend simultaneously in three or more directions. In other words, the structure 10 has additional bending directions in the X-Y plane other than the X and Y directions. This makes it easier to accommodate more complex surfaces of objects to be attracted.

[0116] In the embodiment, when the structure 10 is curved with a certain curvature, the curvature is constant from one side to the other in the X direction, but this is not limited to this. For example, the structure 10 may have a structure that can form a complex curve such that the curvature varies from one side to the other in the X direction. The same applies to curvature in the Y direction. Such a structure can be realized by various configurations, for example, by varying the configuration (size) of the storage unit 1 rather than making them the same.

[0117] In the embodiment, when stress is applied, bending occurs simultaneously in multiple directions, but the present invention is not limited to this. As in the embodiment described in Modification 1-2, bending may occur in only one direction.

[0118] Various embodiments are exemplified below. The embodiments of [Supplementary Note 1] to [Supplementary Note 20] shown below can be combined with each other.

[0119] [Supplementary Note 1] An electrostatic attraction device 100 configured to electrostatically attract an object to be attracted, comprising: a structure 10; and an electrode member 20; the structure 10 is configured so that a curved portion 10a can be formed by deformation of at least a portion of the structure 10; the curved portion 10a is curved from one side to the other side in a first direction (X direction); the first direction is a direction parallel to a plane perpendicular to a thickness direction (Z direction) of the structure 10; the electrode member 20 is provided so that at least a portion of the electrode member 20 is covered by the structure 10, and the electrode member 20 has an attraction surface 20A1 for electrostatically attracting the object to be attracted; and the attraction surface 20A1 of the electrode member is positioned at a position corresponding to the curvature of the curved portion 10a when the structure 10 is in a curved state in which the curved portion 10a is formed.

[0120] [Appendix 2] The electrostatic attraction device 100 according to Appendix 1, wherein the structure 10 has a plurality of accommodation sections 1, each accommodation section 1 having a gap section 1A and a partition wall 1B, the electrode member 20 is accommodated in each of the gap sections 1A, and each of the partition walls 1B partitions adjacent gap sections 1A.

[0121] [Supplementary Note 3] The electrostatic attraction device 100 according to Supplementary Note 2, wherein the partition wall 1B is provided so as to surround a lateral side surface of the electrode member 20.

[0122] [Supplementary Note 4] The electrostatic attraction device 100 according to Supplementary Note 2 or Supplementary Note 3, wherein the plurality of gaps 1A are arranged in a plane.

[0123] [Supplementary Note 5] The electrostatic attraction device 100 according to any one of Supplementary Notes 2 to 4, wherein the accommodation portion 1 is configured so that the attraction surface 20A1 of the electrode member 20 is exposed.

[0124] [Appendix 6] The electrostatic attraction device 100 according to any one of Appendices 1 to 5, wherein the structure 10 has a plurality of first plate-shaped portions 2A and a plurality of second plate-shaped portions 2B, the plurality of first plate-shaped portions 2A are spaced apart from one another, and the plurality of second plate-shaped portions 2B are spaced apart from one another and connected to a pair of adjacent first plate-shaped portions 2A.

[0125] [Appendix 7] The electrostatic adsorption device 100 according to Appendix 6, wherein at least one of the first plate-shaped portion 2A and the second plate-shaped portion 2B is configured in a wavy shape when the structure 10 is viewed in a plane.

[0126] [Appendix 8] The electrostatic adsorption device 100 according to Appendix 6 or 7, wherein each of the first plate-shaped portions 2A is arranged to extend in the first direction, and each of the second plate-shaped portions 2B is arranged to extend in a second direction, and the second direction is a direction parallel to a plane perpendicular to the thickness direction of the structure 10 and a direction intersecting the first direction.

[0127] [Supplementary Note 9] The electrostatic attraction device 100 according to any one of Supplementary Notes 6 to 8, wherein the elasticity of the first plate-shaped portion 2A and the elasticity of the second plate-shaped portion 2B are different from each other.

[0128] [Supplementary Note 10] The electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 9, wherein the curved portion 10a is curved from one side to the other side in a second direction in addition to the first direction, the second direction is a direction parallel to a plane perpendicular to a thickness direction of the structure 10, and the first direction and the second direction are directions intersecting each other.

[0129] [Supplementary Note 11] The electrostatic attraction device 100 according to Supplementary Note 10, wherein the structure 10 is configured so that bending in the first direction and bending in the second direction occur simultaneously.

[0130] [Supplementary Note 12] The electrostatic attraction device 100 according to Supplementary Note 10 or Supplementary Note 11, wherein the structure 10 is configured such that the width in the second direction is constant or increases when a tensile stress is applied in the first direction.

[0131] [Supplementary Note 13] The electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 12, wherein the structure 10 further has a force application unit 3, the force application unit being provided on an edge of the structure 10, and the force application unit 3 being configured to be connectable to a stress generating mechanism 30 that applies a stress to deform the structure 10.

[0132] [Appendix 14] The electrostatic attraction device 100 according to any one of Appendices 1 to 13, wherein the structure 10 is deformable between the curved state and a flat state, and in the flat state, the attraction surfaces 20A1 of the plurality of electrode members 20 are aligned in height.

[0133] [Supplementary Note 15] The electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 14, wherein the attraction target is a wafer or a film.

[0134] [Supplementary Note 16] The electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 15, wherein the structure 10 is made of a resin material or a metal material.

[0135] [Supplementary Note 17] The electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 16, wherein the height difference between the uppermost attraction surface and the lowermost attraction surface is 10 cm or less, the uppermost attraction surface is the attraction surface located at the highest position among the attraction surfaces in the curved portion 10 a, and the lowermost attraction surface is the attraction surface located at the lowest position among the attraction surfaces in the curved portion 10 a.

[0136] [Appendix 18] An electrostatic attraction device 100 configured to electrostatically attract an object to be attracted, comprising: a structure 10; and an electrode member 20; the structure 10 has a curved portion 10a; the curved portion 10a is curved from one side to the other side in a first direction; the first direction is a direction parallel to a plane perpendicular to a thickness direction of the structure 10; the electrode member 20 is provided so as to be at least partially covered by the structure 10; and the electrode member 20 has an attraction surface 20A1 for electrostatically attracting the object to be attracted; and the attraction surface 20A1 of the electrode member 20 is positioned at a position corresponding to the curvature of the curved portion 10a of the structure 10.

[0137] [Supplementary Note 19] A method for correcting warpage of an object to be attracted using the electrostatic attraction device 100 according to any one of Supplementary Notes 1 to 17, the method comprising: an attraction step; and a warpage correction step. In the attraction step, the object to be attracted is attracted to the attraction surface 20A1 of the electrode member 20 of the structure 10 in the curved state, or the object to be attracted is attracted to the attraction surface 20A1 of the electrode member 20 while deforming the structure 10 into the curved state. In the warpage correction step, the structure 10 is deformed from the curved state to a flat state while the object to be attracted is kept attracted to the attraction surface 20A1. In the flat state, height positions of the plurality of attraction surfaces 20A1 are aligned.

[0138] [Supplementary Note 20] A method for attaching an object to be attached using the electrostatic chucking device 100 according to any one of Supplementary Notes 1 to 18, the method comprising: an attachment step, a deformation step, and an attachment step; in the attachment step, the object to be attached is attached to the attachment surface 20A1 of the electrode member 20 of the structure 10; in the deformation step, the structure 10 is brought into the curved state, and the deformation step is a step performed before, after, or together with the attachment step; and in the attachment step, the object to be attached, which is attached to the structure 10 in the curved state, is attached to an attachment target.

[0139] Next, various embodiments will be illustrated. The embodiments of [Supplementary Note 1] to [Supplementary Note 11] shown below can be combined with each other.

[0140] [Appendix 1] An electrostatic adsorption device 100 in which an electrode member 20 for electrostatic adsorption is supported by an expanded auxetic structure (hereinafter referred to as structure 10) having a negative or zero Poisson's ratio in which the dimension in a direction perpendicular to the tensile direction is either elongated or constant.

[0141] [Supplementary Note 2] The electrostatic attraction device 100 according to Supplementary Note 1, wherein the structure 10 is capable of forming a main surface (imaginary surface Sr) that is deformable in a reciprocal direction between a flat surface and a curved surface or between a first curved surface and a second curved surface, the main surface (imaginary surface Sr) constitutes the main surface (imaginary surface Sr) of the electrostatic attraction device 100, and the main surface (imaginary surface) of the electrostatic attraction device 100 is an electrostatic attraction surface.

[0142] [Supplementary Note 3] The electrostatic attraction device 100 according to Supplementary Note 1 or Supplementary Note 2, wherein the structure 10 includes an elastic element (first plate-shaped portion 2A) and a non-elastic element (second plate-shaped portion 2B), and the non-elastic element restricts deformation of the elastic element.

[0143] [Supplementary Note 4] The electrostatic attraction device 100 according to Supplementary Note 3, wherein the elastic element (first plate-shaped portion 2A) is a plurality of chevron-shaped elements that are elastically deformable in at least a first direction (X direction) that is a longitudinal direction thereof, the plurality of chevron-shaped elements are arranged in parallel in a second direction (Y direction) that is perpendicular to the first direction, the plurality of chevron-shaped elements are arranged such that a peak of one chevron-shaped element coincides with a valley of the adjacent chevron-shaped element, and a valley of one chevron-shaped element coincides with a peak of the adjacent chevron-shaped element, respectively, in the first direction, the non-elastic element is connected in the second direction between the peak or valley of one chevron-shaped element that maximizes the distance between the adjacent chevron-shaped elements and the valley or peak of the adjacent chevron-shaped element, and the chevron-shaped element and the non-elastic element form an angle greater than 0° and less than 90° at the connection point.

[0144] [Supplementary Note 5] The electrostatic attraction device 100 according to Supplementary Note 3, wherein the elastic element (first plate-shaped portion 2A) is a plurality of chevron-shaped elements that are elastically deformable in at least the first direction (X direction) that is a longitudinal direction thereof, the plurality of chevron-shaped elements are arranged in parallel in a second direction (Y direction) perpendicular to the first direction, and the chevron-shaped elements are arranged such that a crest of one chevron-shaped element coincides with a crest of an adjacent chevron-shaped element, and a valley of one chevron-shaped element coincides with a valley of the adjacent chevron-shaped element, respectively, in the first direction, and the non-elastic element connects the crests of the adjacent chevron-shaped element to the adjacent chevron-shaped element on one side of the second direction, and the non-elastic element connects the valleys of the adjacent chevron-shaped element to the second direction on the other side of the second direction.

[0145] [Supplementary Note 6] The electrostatic attraction device 100 according to Supplementary Note 2, wherein the electrostatic attraction surface of the structure 10 can generate a double curved surface or a single curved surface.

[0146] [Supplementary Note 7] The electrostatic attraction device 100 according to Supplementary Note 1 or Supplementary Note 2, further comprising a driving means for applying a bending stress to the structure 10.

[0147] [Supplementary Note 8] The electrostatic attraction device 100 according to Supplementary Note 2, wherein when the main surface of the structure 10 is deformed from a flat surface to a curved surface or from the first curved surface to the second curved surface, the area of ​​the main surface of the structure 10 can expand or remain constant.

[0148] [Supplementary Note 9] An electrostatic attraction method using an electrostatic attraction device 100 to electrostatically attract a film with the electrostatic attraction device 100, transport the film to an object to be attracted, and release the film from the surface of the object to be attracted, the method comprising: using the electrostatic attraction device 100 described in any one of Supplementary Note 1 to Supplementary Note 8 as the electrostatic attraction device 100; and applying a bending stress to the electrostatic attraction surface of the electrostatic attraction device 100 during the period from when the electrostatic attraction device 100 electrostatically attracts the film to when the film is released from the surface of the object to deform the electrostatic attraction surface of the electrostatic attraction device 100 into a curved shape, thereby deforming the electrostatically attracted film into a curved shape.

[0149] [Supplementary Note 10] The electrostatic attraction method according to Supplementary Note 9, wherein the deformation of the electrostatic attraction surface of the electrostatic attraction device 100 is performed by a robot arm.

[0150] [Supplementary Note 11] The electrostatic attraction method according to Supplementary Note 9 or Supplementary Note 10, wherein the structure 10 constituting the electrostatic attraction device 100 is deformed so that an area of ​​the electrostatic attraction surface of the structure 10 is enlarged or remains constant.

[0151] 100 electrostatic adsorption device, 10 structure, 10a curved portion, 1 storage portion, 1A gap portion, 1B partition wall, 1C gap, 2 plate-shaped portion, 2A first plate-shaped portion (chevron-shaped element, high elasticity portion, elastic element), 2A1 inclined portion, 2A2 protruding portion, 2A3 end surface, R1 first high elasticity rod, R2 second high elasticity rod, R3 third high elasticity rod, R4 fourth high elasticity rod, R5 fifth high elasticity rod, 2B second plate-shaped portion (low elasticity portion, non-elastic element), 2B1 end surface, r1 first low elasticity rod, r2 second low elasticity rod, r3 third low elasticity rod, r4 fourth low elasticity rod, r5 fifth low elasticity rod, 2C third plate-shaped portion, 2C1 end surface, 3 force application portion, 20 electrode member, 20A base portion, 20A1 adsorption surface, 20B insertion portion, 20B1 Slit, 20B2: Cutout portion, 20C: Gap, 20a: Top portion, 30: Stress generating mechanism (driving means), 50: Voltage application device, Sr: Virtual surface

Claims

1. An electrostatic adhesion device configured to electrostatically adsorb an object to be attracted, comprising a structure and an electrode member, the structure being configured so that a curved portion can be formed by deformation of at least a portion of the structure, the curved portion being curved from one side to the other side in a first direction, the first direction being a direction parallel to a plane perpendicular to a thickness direction of the structure, the electrode member being arranged so that at least a portion of the electrode member is covered by the structure, and the electrode member has an adhesion surface for electrostatically adsorbing the object to be attracted, and the adhesion surface of the electrode member is positioned at a position corresponding to the curvature of the curved portion when the structure is in a curved state in which the curved portion is formed.

2. An electrostatic adsorption device as described in claim 1, wherein the structure has a plurality of storage sections, each of the storage sections has a gap and a partition wall, an electrode member is stored in each of the gaps, and each of the partition walls partitions adjacent gaps.

3. An electrostatic adhesion device according to claim 2, wherein the partition wall is provided so as to surround a lateral side surface of the electrode member.

4. An electrostatic adhesion device according to claim 2 or 3, wherein a plurality of the gaps are arranged in a planar manner.

5. An electrostatic attraction device according to claim 2 or 3, wherein the container is configured so that the attraction surface of the electrode member is exposed.

6. An electrostatic adsorption device as claimed in any one of claims 1 to 3, wherein the structure has a plurality of first plate-shaped portions and a plurality of second plate-shaped portions, the plurality of first plate-shaped portions are spaced apart from one another, and the plurality of second plate-shaped portions are spaced apart from one another and connected to an adjacent pair of the first plate-shaped portions.

7. An electrostatic adsorption device as described in claim 6, wherein at least one of the first plate-shaped portion and the second plate-shaped portion is configured in a wavy shape when the structure is viewed in a plane.

8. An electrostatic adsorption device as described in claim 6, wherein each of the first plate-shaped portions is arranged to extend in the first direction, and each of the second plate-shaped portions is arranged to extend in a second direction, the second direction being a direction parallel to a plane perpendicular to the thickness direction of the structure and a direction intersecting the first direction.

9. An electrostatic attraction device according to claim 6, wherein the elasticity of the first plate-shaped portion and the elasticity of the second plate-shaped portion are different.

10. An electrostatic adhesion device as claimed in any one of claims 1 to 3, wherein the curved portion is curved from one side to the other side in a second direction in addition to the first direction, the second direction is a direction parallel to a plane perpendicular to the thickness direction of the structure, and the first direction and the second direction are directions intersecting each other.

11. An electrostatic adhesion device according to claim 10, wherein the structure is configured so that bending in the first direction and bending in the second direction occur simultaneously.

12. An electrostatic adhesion device according to claim 10, wherein the structure is configured such that the width in the second direction remains constant or increases when a tensile stress is applied in the first direction.

13. An electrostatic adhesion device as defined in any one of claims 1 to 3, wherein the structure further has a force application portion, the force application portion being provided on an edge portion of the structure, and the force application portion being configured to be connectable to a stress generating mechanism that applies stress to deform the structure.

14. An electrostatic adhesion device as defined in any one of claims 1 to 3, wherein the structure is deformable between the curved state and a flat state, and in the flat state, the adhesion surfaces of the multiple electrode members are aligned at the same height.

15. An electrostatic attraction device according to any one of claims 1 to 3, wherein the object to be attracted is a wafer or a film.

16. An electrostatic attraction device according to any one of claims 1 to 3, wherein the structure is made of a resin material or a metal material.

17. An electrostatic adhesion device as claimed in any one of claims 1 to 3, wherein the height difference between an uppermost adhesion surface and a lowermost adhesion surface is 10 cm or less, the uppermost adhesion surface is the adhesion surface located at the highest position among the adhesion surfaces in the curved portion, and the lowermost adhesion surface is the adhesion surface located at the lowest position among the adhesion surfaces in the curved portion.

18. An electrostatic adsorption device configured to electrostatically adsorb an object to be adsorbed, comprising a structure and an electrode member, the structure having a curved portion, the curved portion being curved from one side to the other side in a first direction, the first direction being a direction parallel to a plane perpendicular to a thickness direction of the structure, the electrode member being arranged so that at least a portion of the electrode member is covered by the structure, and the electrode member has an adsorption surface for electrostatically adsorbing the object to be adsorbed, and the adsorption surface of the electrode member is positioned at a position corresponding to the curvature of the curved portion of the structure.

19. A method for straightening a warp of an object to be attracted using an electrostatic attraction device according to any one of claims 1 to 3, comprising: an attraction step; and a warp straightening step, in which, in the attraction step, the object to be attracted is attracted to the attraction surface of the electrode member of the structure in the curved state, or the object to be attracted is attracted to the attraction surface of the electrode member while the structure is being deformed into the curved state, and, in the warp straightening step, the structure is deformed from the curved state to a flat state while the object to be attracted is kept attracted to the attraction surface, and in the flat state, the height positions of the plurality of attraction surfaces are aligned.

20. A method for attaching an object to be attached using an electrostatic adhesion device according to any one of claims 1 to 3 and claim 18, comprising an adhesion step, a deformation step, and an attachment step, in which the adhesion step involves adsorbing the object to be attached to the adhesion surface of the electrode member of the structure, the deformation step involves bringing the structure into the curved state, and the deformation step is a step which is performed before, after, or together with the adhesion step, and the attachment step involves attaching the object to be attached which has been adsorbed to the structure in the curved state to a target body.

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