JP2019114590A - Vacuum suction member - Google Patents

Abstract

To provide a vacuum suction member capable of improving overall flatness of a base plate including an outer region.SOLUTION: A vacuum suction member comprises: a base body 1; a plurality of convex sections 10 protruded from a main surface 102 of the base body 1; and a ventilation passage 20 which passes through the base body 1 and has an opening section 202 on the main surface 102 of the base body 1. The plurality of convex sections 10 are made up of an inner convex section group 11 arranged in an inner region Son the main surface 102 of the base body 1 and an outer convex section group 12 arranged in an annular outer region Ssurrounding the inner region Son the main surface 102 of the base body 1. A position (a protrusion height H) of an edge face 1220 measured from the main surface 102 of the base body 1 on each of a plurality of designated outer convex sections 122 which is at least a portion of a plurality of outer convex sections 122 constituting the outer convex section group 12 is higher than the position (a protrusion height H) of an edge face 1120 measured from the main surface 102 of the base body 1 on each of a plurality of inner convex sections 112 constituting the inner convex section group 11.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vacuum suction member used to vacuum hold a substrate such as a semiconductor wafer.

  An adsorption portion made of porous ceramic having an adsorption surface for adsorbing and holding a workpiece such as a semiconductor wafer, and an annular seal portion formed of a sponge-like elastic member surrounding the adsorption portion and having an upper surface height higher than the adsorption surface There has been proposed a chuck table provided with (see, for example, Patent Document 1).

  When the workpiece is placed on the chuck table, the workpiece is in contact with the annular seal at least in the peripheral region. In this state, when a negative pressure region is generated on the side opposite to the suction surface of the suction portion, a negative pressure region is formed in the space defined by the annular seal portion and the workpiece. In response to this, a suction force acting on the work surface acts on the work surface, and the annular seal portion is formed until the height of the upper surface of the annular seal portion becomes the same as the height of the work surface due to the work object approaching the work surface. Is crushed. Thereby, the flatness of the workpiece is improved.

JP, 2014-072510, A

However, it may bow or sag in the outer area, which is the peripheral area of the substrate. In this case, even if the flatness of the substrate is ensured in the inner region, it locally decreases in the outer region. As a result, it becomes difficult to perform predetermined processing such as etching processing for forming a desired circuit on the outer region of the substrate.
Then, an object of this invention is to provide the vacuum suction member which can aim at the improvement of the whole planarity of a board | substrate including an outer side area | region.

  The vacuum suction member of the present invention comprises a substrate, a plurality of convex portions projecting from the main surface of the substrate, a vacuum suction path having an opening in the main surface of the substrate passing through the inside of the substrate, and a plurality of the plurality An inner convex group disposed in an inner area of the main surface of the base and an outer convex group disposed in an annular outer area surrounding the inner area of the main surface of the base An end surface position based on the main surface of the base of each of the plurality of designated outer convex portions constituting at least a part of the outer convex portion group is constituted by a plurality of inner convex portions constituting the inner convex portion group And a part of each of the plurality of designated outer convex parts is made of an elastic material having a lower elastic modulus than the remaining parts, which is higher than the end face position based on the main surface of the base of each part It is characterized by

  According to the vacuum suction member of the present invention, the substrate is mounted on the vacuum suction member on the main surface side of the substrate, whereby at least a part of the plurality of convex portions protruding from the main surface of the substrate is the substrate Is supported. Because the end surface position of each designated outer convex portion (description of “position of surface” means “position of the surface with reference to the main surface of the base”) is higher than the end surface position of each inner convex portion Even if at least a portion of the outer region of the substrate is warped or sagging, at least a portion of the outer region of the substrate can be supported by the corresponding designated outer convex portion. At this time, at least a portion of the outer region of the substrate is received from the designated outer convex portion by elastically deforming an elastic material constituting a portion of the designated outer convex portion so as to lower the end surface position of the designated outer convex portion. Drag can be mitigated.

  In this state, air is discharged from the space sandwiched between the main surface of the base and the back surface of the substrate through the ventilation path to form a negative pressure region in the space. As a result, the inner region of the substrate is supported by the inner convex group, and the outer region of the substrate is supported by the plurality of designated outer convex portions constituting at least a part of the outer convex group. Even if at least a part of the outer region of the substrate is warped or drooping, the elastic material forming a part of the designated outer convex portion causes the end face position of the designated outer convex portion to coincide with the end face position of the inner convex portion. Can be elastically deformed. In addition, since a part of the designated outer convex part is made of an elastic material having a lower elastic modulus than the remaining part, it is more elastic than in the case where all of the designated outer convex parts are made of the elastic material. The amount of change in the end surface position of the designated outer convex portion due to elastic deformation is limited. Therefore, even in the case of the substrate having the above-mentioned shape, the substrate can be held by vacuum suction so as to improve the overall flatness of the substrate surface.

  In the vacuum suction member according to the present invention, the elastic material wherein each of the plurality of designated outer convex portions is provided continuously to a first element protruding from the main surface of the base and an end face of the first element And an end surface position of the second element with respect to the main surface of the base is an end surface position with respect to the main surface of the base of each of the plurality of inner protrusions. Higher than is preferable.

  According to the vacuum suction member of the configuration, the second element constituting a part of the designated outer convex part is an end face of the designated outer convex part even if at least a part of the outer region of the substrate is warped or sagging. The position can be elastically deformed so as to make the end surface position of the second element coincide with the end surface position of the inner convex portion. Also, while the second element which is a part of the designated outer convex portion is made of an elastic material, the first element which is the remaining part has a higher elastic modulus than the second element, so the elastic deformation of the elastic material The amount of change in the end surface position of the designated outer convex portion is suppressed. Therefore, even in the case of the substrate having the above-mentioned shape, the substrate can be held by vacuum suction so as to improve the overall flatness of the substrate surface.

In the vacuum suction member according to the present invention, the elastic modulus E [Pa] of the elastic material, the length L [m] of the elastic material in the direction perpendicular to the main surface of the substrate and the main surface of the elastic material The cross-sectional area S [m ² ] in parallel cross sections satisfies the condition represented by 4 [MPa] ≦ E and 1.0 × 10 ⁻⁷ ≦ L / (E × S) ≦ 5.0 × 10 ⁻⁶ Is preferred.

  According to the vacuum suction member having the above configuration, the elastic modulus E, the length L, and the cross-sectional area S of the elastic material constituting a part of the designated outer convex portion are substrates having a warp or sag in at least a part of the outer region. It is designed appropriately from the viewpoint of improving the flatness of the

  In the vacuum suction member according to the present invention, each of the plurality of designated outer convex portions is a first element which is configured separately from the base, and the first element is supported by the base at an end It is preferable that a second element configured of the supporting elastic element is provided, and an end surface position of the first element is higher than an end surface position of each of the plurality of inner convex portions.

  According to the vacuum suction member of the configuration, the second element constituting a part of the designated outer convex part is an end face of the designated outer convex part even if at least a part of the outer region of the substrate is warped or sagging. The position can be elastically deformed so as to make the end surface position of the first element coincide with the end surface position of the inner convex portion. Also, while the second element which is a part of the designated outer convex portion is made of an elastic material, the first element which is the remaining part has a higher elastic modulus than the second element, so the elastic deformation of the elastic material The amount of change in the end surface position of the designated outer convex portion is suppressed. Therefore, even in the case of the substrate having the above-mentioned shape, the substrate can be held by vacuum suction so as to improve the overall flatness of the substrate surface.

  In the vacuum suction member according to the present invention, the vacuum suction member further comprises a recess provided recessed from the main surface of the base, the first element being partially displaceably inserted in the recess, and the second element being the recess It is preferable that the first element is supported while being accommodated inside and supported by the bottom of the recess.

  According to the vacuum suction member of the configuration, the first element is displaced while being guided by the recess along with the elastic deformation of the second element, whereby the end face position of the designated outer convex part and hence the end face position of the first element is highly accurate It can be adjusted with

  The vacuum suction member of the present invention further includes an annular convex portion protruding from the main surface of the base so as to surround each of the plurality of convex portions, and an end face of the annular convex portion with respect to the main surface of the base An end surface position relative to the main surface of the base of each of the plurality of designated outer convex portions, or a position lower than an end surface position relative to the main surface of the base of each of the plurality of designated outer convex portions; Preferably they are identical.

  According to the vacuum suction member of the configuration, the space between the back surface of the substrate supported by at least a part of the convex portion and the main surface of the base is surrounded by the annular convex portion. A stronger negative pressure region may be formed in the space. Therefore, when the negative pressure region is formed in the space, the end face of the back surface of the substrate can be reliably brought into contact with the end faces of the plurality of inner protrusions and the plurality of designated outer protrusions. Further, when a gap exists between the end face of the annular convex portion and the back surface of the substrate, when a negative pressure region is formed in the space, the flow velocity of air flowing into the space through the gap locally increases. Bernoulli force can be exerted on the outer area of the substrate. Therefore, when the negative pressure region is formed in the space, the back surface of the substrate can be more reliably brought into contact with the end surfaces of the plurality of designated outer convex portions.

The top view of the vacuum suction member as a 1st embodiment of the present invention. The longitudinal cross-sectional view of the vacuum suction member which followed the II-II line of FIG. Explanatory drawing regarding the function of the vacuum suction member as a 1st embodiment of the present invention. Explanatory drawing regarding the function of the vacuum suction member as a 1st embodiment of the present invention. Explanatory drawing regarding the function of the vacuum suction member as a 1st embodiment of the present invention. The longitudinal cross-sectional view corresponding to FIG. 2 of the vacuum suction member as 2nd Embodiment of this invention. Explanatory drawing regarding the function of the vacuum suction member as a 2nd embodiment of the present invention. Explanatory drawing regarding the function of the vacuum suction member as a 2nd embodiment of the present invention. Explanatory drawing regarding the function of the vacuum suction member as a 2nd embodiment of the present invention. The longitudinal cross-sectional view corresponding to FIG. 2 of the vacuum suction member as 3rd Embodiment of this invention.

First Embodiment
(Constitution)
The vacuum suction member according to the first embodiment of the present invention shown in FIGS. 1 and 2 comprises a base 1, a plurality of projections 10 projecting from the main surface 102 of the base 1, and a plurality of projections 10. An annular convex portion 14 extending so as to surround and project from the main surface 10 of the base 1 and a ventilation path 20 having an opening 202 in the main surface 102 of the base 1 through the inside of the base 1 .

The substrate 1 is made of, for example, a substantially flat plate-like sintered body of ceramic such as SiC, AlN, Al ₂ O ₃ or the like. Each of the plurality of protrusions 10, the annular protrusion 14 and the passage 20 is formed by grinding, blasting, milling, laser processing, or a combination thereof. The main surface 102 of the base 1 is formed in a substantially planar shape.

  The plurality of convex portions 10 are arranged in a lattice form such as a triangular lattice or a square lattice on the main surface 102 of the base body 1, and are arranged along each of a plurality of concentric circles or a plurality of radiations extending from the center They may be regularly arranged, such as regularly arranged along each of the two, or may be irregularly arranged. Each convex portion 10 is a columnar body, a hemisphere, a semi-elliptic sphere or a frustum having a bottom or a lower base of a small area on the end face or upper bottom of a substantially columnar, substantially frustum shape, columnar body or frustum shape It may be formed in various shapes, such as a substantially columnar shape with a plurality of steps, such as the ones on which it rides.

  In the longitudinal sectional view of the vacuum suction member, in addition to the substantially rectangular shape, the shape of the annular convex portion 14 is a substantially trapezoidal shape, a semielliptical shape, a perfect circle shape, or a combination of a rectangle and a semicircle having one side of the rectangle as a diameter The shape may be various, such as the shape that has been made. The annular convex portion 14 may be omitted.

The plurality of convex portions 10 are configured by the inner convex portion group 11 and the outer convex portion group 12. Inner convex portion group 11 is composed of a plurality of inner protrusions 112 are arranged from the center in the main surface 102 of the substrate 1 to the circular inner area S ₁ of radius R _1. The outer convex group 12 is constituted by a plurality of outer convex parts 122 disposed in an annular outer area S ₂ having an outer edge of radius R ₂ from the center and surrounding the inner area S ₁ on the main surface 102 of the base 1 ing. It is coincident with the inner edge of the outer edge and the annular convex portion 14 of the outer region S _2.

To the total area of the inner region S ₁ and the outer region ^{_{S 2 (= πR 2 2)}} , the area of the outer region _{S 2 (= π (R 2} 2 -R 1 2)) Ratio of ^{_{(= 1-R 1 2 /}} R ₂ ^2), the inner region S ₁ and the outer area S ₂ are defined to be within the scope of example 0.03 to 0.20. The outer edge of the inner area S ₁ is not limited to the annular shape, or may be a wavy or zigzag line shape extending along the torus. The outer edge of the outer region S ₂ is not limited to the annular shape, or may be a wavy or zigzag line shape extending along the torus.

  In the main surface 102 of the base 1, the arrangement of the plurality of inner projections 112 and the arrangement of the plurality of outer projections 122 may be the same, and the plurality of inner projections 112 are arranged in a triangular lattice shape. On the other hand, the plurality of outer projections 122 may be arranged to be arranged along one circle or a plurality of concentric circles. The shape of each inner protrusion 112 and the shape of each outer protrusion 122 may be the same or different.

The position (protruding height H ₂ ) of the end face 1220 based on the major surfaces 102 of the plurality of designated outer convex portions 122 constituting at least a part of the outer convex portion group 12 with respect to the inner convex portion group 11 It is higher than the position (protruding height H ₁ ) of the end face 1120 based on the main surface 102 of the base 1 of each of the plurality of inner projections 112 to be configured. In the present embodiment, the plurality of outer protrusions 122 that constitute "all" of the outer protrusion group 12 correspond to "designated outer protrusions", but as another embodiment, "only a part of the outer protrusion group 12 is A plurality of outside convex parts 122 which constitute "" may correspond to a "designated outside convex part".

The height difference H ₂ −H ₁ between the positions of the end surfaces 1220 of the plurality of designated outer convex portions 122 and the positions of the end surfaces 1120 of the plurality of inner convex portions 112 is, for example, in the range of ₂ μm to 20 μm. include. The position (protruding height H ₄ ) of the end surface 140 of the annular convex portion 14 with respect to the main surface 102 of the base 1 is the end surface 1220 with respect to the main surface 102 of each of the plurality of designated outer convex portions 122. position the position (protruding height H ₂₎ lower or the end surface 1220 than (protruding height H ₂₎ to be identical. In the present embodiment, at least a portion of each of the end surfaces 1220 of the plurality of designated outer convex portions 122 and at least a portion of each of the end surfaces 1120 of each of the plurality of inner convex portions 112 It is parallel.

  A portion of each designated outer convex portion 122 is made of an elastic material having a lower elastic modulus than the remaining portion. Specifically, each designated outer convex portion 122 is constituted by a first element 1221 projecting from the main surface 102 of the base body 1 and an elastic material provided continuously to an end face of the first element 1221. And a second element 1222. The first element 1221 may be integrally formed with the base 1 or may be constituted by a separate member attached to the base 1. When the first element 1221 is formed of a ceramic sintered body such as SiC, the second element 1222 is made of, for example, silicon resin, fluorine resin (PFA) or polyimide resin, metal spring or silicon nitride spring, etc. It is comprised by the raw material whose elasticity modulus is lower than a body, or the member whose spring constant is low.

The end face position (protruding height H ₂₁ ) of the first element 1221 is lower than the position (protruding height H ₁ ) of the end face 1120 of each inner convex portion 112, and the position (protruding height) of the end face 1120 of each inner convex portion 112 It may be the same as H ₁ ). The end surface position (projecting height H ₂₁ + H ₂₂ ) of the second element 1222, that is, the position (projecting height H ₂ ) of the end surface 1220 of the designated outer convex portion 122 is the position (projecting height) of the end surface 1120 of each inner convex portion 112 H ₁ ) higher than.

Modulus of elastic material constituting the second element 1222 E [Pa], the length of the perpendicular direction of the main surface 102 of the substrate 1 of elastic material L [m] (see H ₂₂ in FIG. 2) and the substrate of the elastic material The combination of the cross-sectional area S [m ² ] in the cross section parallel to the main surface 102 of 1 satisfies the conditions represented by the relational expressions (1) and (2).

  4 [MPa] E E .. (1).

1.0 × 10 ⁻⁷ ≦ L / (E × S) ≦ 5.0 × 10 ⁻⁶ .. (2).

  A pressure adjusting device or vacuum suction which adjusts the air pressure of the ventilation passage 20 through the opening (opening in the surface opposite to the main surface 102) different from the opening 202 in the main surface 102 of the base 1 It is connected to a device (not shown).

  1 and 2 schematically show the vacuum suction member, and the aspect ratio, interval, number, etc. of the components of the vacuum suction member are basically different from the actual design values. This is the same in all embodiments.

(function)
According to the vacuum suction member as the first embodiment of the present invention, the substrate W is mounted on the vacuum suction member on the main surface 102 side of the substrate 1 so that the substrate W is at least partially projected by the convex portion 10. Supported (see FIGS. 3A and 3B). The position of the end face 1220 of each designated outer convex portion 122 is higher than the position of the end face 1120 of each inner convex portion 112 (see FIG. 2). Therefore, even when the substrate W is warped in at least a part of the outer region X _2, it may be supported by specified outer projection 122 which at least part of the outer region X ₂ of the substrate W corresponding (see FIG. 3A ). On the other hand, even when the substrate W is hanging at least a part of the outer region X _2, at least a portion of the outer region X ₂ of the substrate W can be supported by the corresponding designated outer projection 122 (see FIG. 3B). Under the present circumstances, the 2nd element 1222 (elastic material) which constitutes a part of designated outside convex part 122 elastically deforms so that the position of end face 1220 of the designated outside convex part 122 concerned may fall, and the outside field of substrate W The resistance that at least a part of X ₂ receives from the designated outer protrusion 122 can be alleviated.

In this state, the air is discharged from the space between the back surface W ₂ of the main surface 102 and the substrate W of the substrate 1 through the vent path 20, a negative pressure region is formed in the space, the substrate W On the other hand, a force acts on the main surface 102 of the substrate 1 (see white arrows in FIGS. 3A and 3B). As a result, while the inner region X ₁ of the substrate W is supported by a plurality of inner convex portion 112, the outer region X ₂ of the substrate W is supported by a plurality of specified outer projection 122.

Even if upward warping or sagging on at least a portion of the outer region X ₂ of the substrate W, the second element 1222 which constitutes a part of the designated outer protrusions 122 (elastic material), the end face of the designated outer projection 122 It can be elastically deformed so as to match the position of 1220 with the position of the end face 1120 of the inner protrusion 112 (see FIGS. 3A and 3B → FIG. 3C). Further, since the second element 1222 is made of an elastic material having a lower elastic modulus than the first element 1221, the elasticity of the elastic material is greater than when all of the designated outer convex portions 122 are made of the elastic material. The amount of change in the position of the end face 1220 of the designated outer convex portion 122 due to the deformation is limited.

Therefore, even in the substrate W having a shape as described above, the substrate W can be held vacuum suction as improving the overall flatness of the surface W ₁ of the substrate W can be achieved. Then, the surface W ₁ of the substrate W, even in the outer region X ₂ not only the inner region X _1, such as an etching process for circuit formation of the desired pattern, the predetermined processing may be performed.

Second Embodiment
(Constitution)
In the vacuum suction member according to the second embodiment of the present invention shown in FIG. 4, each designated outer convex portion 122 is supported by the first element 1221 configured separately from the base 1 and the base 1. And a second element 122 constituted by an elastic element supporting the first element 1221 at its end in the closed state. The end surface position of the first element 1221, that is, the position of the end surface 1220 of the designated outer convex portion 122 is higher than the position of the end surface 1120 of each inner convex portion 112. Specifically, the vacuum suction member includes a concave portion 104 which is provided in a substantially columnar shape and recessed from the main surface 102 of the base 1. A substantially columnar first element 1221 is partially displaceably inserted in the recess 104. The second element 1222 is accommodated inside the recess 104 and supports the first element 1221 while being supported by the bottom of the recess 104.

  The configuration other than the configuration of the designated outer convex portion 122 is the same as that of the vacuum suction member of the first embodiment, so the same reference numerals are used and the description is omitted.

(function)
According to the vacuum suction member as the second embodiment of the present invention, the substrate W is mounted on the vacuum suction member on the main surface 102 side of the substrate 1 so that the substrate W is at least partially projected by the convex portion 10. Supported (see FIGS. 5A and 5B). The position of the end face 1220 of each designated outer convex portion 122 is higher than the position of the end face 1120 of each inner convex portion 112 (see FIG. 4). Therefore, even when the substrate W is warped in at least a part of the outer region X _2, it may be supported by specified outer projection 122 which at least part of the outer region X ₂ of the substrate W corresponding (see FIG. 5A ). On the other hand, even when the substrate W is hanging at least a part of the outer region X _2, at least a portion of the outer region X ₂ of the substrate W can be supported by the corresponding designated outer projection 122 (see FIG. 5B). Under the present circumstances, the 2nd element 1222 (elastic material) which constitutes a part of designated outside convex part 122 elastically deforms so that the position of end face 1220 of the designated outside convex part 122 concerned may fall, and the outside field of substrate W The resistance that at least a part of X ₂ receives from the designated outer protrusion 122 can be alleviated.

In this state, the air is discharged from the space between the back surface W ₂ of the main surface 102 and the substrate W of the substrate 1 through the vent path 20, a negative pressure region is formed in the space, the substrate W On the other hand, a force acts on the main surface 102 of the substrate 1 (see white arrows in FIGS. 5A and 5B). As a result, while the inner region X ₁ of the substrate W is supported by a plurality of inner convex portion 112, the outer region X ₂ of the substrate W is supported by a plurality of specified outer projection 122.

Even if upward warping or sagging on at least a portion of the outer region X ₂ of the substrate W, the second element 1222 which constitutes a part of the designated outer protrusions 122 (elastic material), the end face of the designated outer projection 122 It can be elastically deformed so as to match the position of 1220 with the position of the end face 1120 of the inner convex portion 112 (see FIGS. 5A and 5B → FIG. 5C). In addition, since the second element 1222 is made of an elastic material having a lower elastic modulus than the first element 1221 or a member having a low spring constant, it is more preferable than the case where the entire designated outer convex portion 122 is made of the elastic material. Also, the amount of change in the position of the end face 1220 of the designated outer convex portion 122 due to the elastic deformation of the elastic material is limited.

Therefore, even in the substrate W having a shape as described above, the substrate W can be held vacuum suction as improving the overall flatness of the surface W ₁ of the substrate W can be achieved. Then, the surface W ₁ of the substrate W, even in the outer region X ₂ not only the inner region X _1, such as an etching process for circuit formation of the desired pattern, the predetermined processing may be performed.

Third Embodiment
(Constitution)
In the vacuum suction member according to the third embodiment of the present invention shown in FIG. 6, the second element 1222 is fixed to the main surface 102 of the base 1 and the first element 1221 is fixed to the end face of the second element 1221. It is done. The configuration other than the configuration of the designated outer convex portion 122 is the same as that of the vacuum suction member of the first embodiment, so the same reference numerals are used and the description is omitted.

(function)
According to the vacuum suction member according to a third embodiment of the present invention, similarly to the vacuum suction member according to the second embodiment of the present invention, the substrate is drooping or are warped in the outer region X ₂ as Even in the case of W, the substrate W can be held by vacuum suction so as to improve the overall flatness of the surface W ₁ of the substrate W (see FIGS. 5A to 5C). Then, the surface W ₁ of the substrate W, even in the outer region X ₂ not only the inner region X _1, such as an etching process for circuit formation of the desired pattern, the predetermined processing may be performed.

(Example)
Example 1
The vacuum suction member of Example 1 was produced according to the first embodiment (see FIG. 1). A substrate 1 was produced from a substantially disk-shaped silicon carbide (SiC) ceramic sintered body having an outer diameter of 300 mm and a thickness of 1.2 mm.

In the inner region S ₁ of φ292 [mm] of the main surface 102 of the substrate 1, the diameter was placed on each lattice point of a triangular lattice of pitch 3.5 [mm] φ1.0 [mm] , the protruding height H ₁ = A plurality of 150 [μm] substantially cylindrical projections are formed as the plurality of inner protrusions 112.

Inner diameter φ292 of the main surface 102 of the substrate 1 [mm], the outer diameter φ299 diameter located at each lattice point of a triangular lattice of pitch 3.5 [mm] in the outer region S ₂ of the annular [mm] φ1.0 [ A plurality of substantially cylindrical protrusions having a projection height H ₂₁ = 150 μm] are formed as the first element 1221. A plurality of substantially cylindrical protrusions made of silicon resin and having a diameter of φ1.0 [mm] and a height of H ₂₂ = 10 [μm] fixed to the end face of the protrusion are formed as the second element 1222. That is, in the outer region S ₂ of the main surface 102 of the substrate 1, the diameter ø1.0 [mm], the protruding height H ₂ = 160 substantially cylindrical plurality of outer projection 122 of the [[mu] m] is a pitch 3.5 [ mm] were placed at each grid point of the triangular grid. The second element 1222 is fixed by depositing on the first element 1221. Density of the specified outer projection 122 (to the area of the outer region S _2, the total percentage of the area of the end faces of the plurality of specified outer projection 122) is 6.43%.

The elastic modulus E (Young's modulus) of hardness 70 (meaning hardness according to type A durometer (JIS K6253) which is an elastic material. The same applies hereinafter) is 40.3 [MPa] and is represented by the relational expression (1) The conditions are met. Since the length L (height H ₂₂ ) of the second element 1222 is 1.0 × 10 ⁻⁵ [m] and the cross-sectional area S is 7.85 × 10 ⁻⁷ [m ² ], L / ( ² ) E × S) = 3.16 × 10 ⁻⁷ , which satisfies the condition represented by the relational expression (2).

On the main surface 102 of the base 1, an annular convex having an outer diameter of 299 [mm], a width of 0.5 [mm], and a protruding height H ₄ = 147 [μm] is formed as the annular convex part 14. In the base 1, one through hole penetrating in the thickness direction of φ 3.0 [mm] at the center of the main surface 102 was formed as the ventilation path 20.

(Example 2)
A vacuum suction member of Example 2 was produced in the same manner as Example 1 except that the length L (height H ₂₂ ) of the second element 1222 was 2.0 × 10 ⁻⁵ [m].

(Example 3)
The vacuum suction member of Example 3 was produced in the same manner as Example 1 except that the length L (height H ₂₂ ) of the second element 1222 was 3.0 × 10 ⁻⁵ [m].

(Example 4)
A vacuum suction member of Example 4 was produced in the same manner as Example 1, except that the length L (height H ₂₂ ) of the second element 1222 was 4.0 × 10 ⁻⁵ [m].

(Example 5)
The vacuum suction member of Example 5 was produced in the same manner as Example 1 except that the length L (height H ₂₂ ) of the second element 1222 was 5.0 × 10 ⁻⁵ [m].

(Example 6)
Example 6 is the same as Example 2 except that the diameter φ of each of the first element 1221 and the second element 1222 is 1.2 [mm], and the density of the designated outer convex portion 122 is 9.26%. The vacuum suction member of

(Example 7)
Example 7 is the same as Example 2 except that the diameter φ of each of the first element 1221 and the second element 1222 is 1.4 [mm], and the density of the designated outer convex portion 122 is 12.6%. The vacuum suction member of

(Example 8)
Example 8 is the same as Example 2 except that the diameter φ of each of the first element 1221 and the second element 1222 is 1.6 [mm], and the density of the designated outer convex portion 122 is 16.5%. The vacuum suction member of

(Example 9)
Example 9 is the same as Example 2 except that the diameter φ of each of the first element 1221 and the second element 1222 is 1.8 [mm], and the density of the designated outer convex portion 122 is 20.8%. The vacuum suction member of

(Example 10)
A vacuum suction member of Example 10 was produced in the same manner as in Example 2 except that the second element 1222 was formed of a silicone resin having a hardness of 30 and an elastic modulus E of 5.4 [MPa].

(Example 11)
A vacuum suction member of Example 11 was produced in the same manner as Example 2 except that the second element 1222 was formed of a silicone resin having a hardness of 40 and an elastic modulus E of 8.9 [MPa].

(Example 12)
A vacuum suction member of Example 12 was produced in the same manner as in Example 2 except that the second element 1222 was formed of a silicon resin of hardness 50 having an elastic modulus E of 14.2 [MPa].

(Example 13)
A vacuum suction member of Example 13 was produced in the same manner as in Example 2 except that the second element 1222 was formed of a silicone resin having a hardness of 60 and an elastic modulus E of 28.1 [MPa].

(Example 14)
The diameter φ of each of the first element 1221 and the second element 1222 is 2.0 [mm], the density of the designated outer convex portion 122 is 25.7%, and the second element 1222 has an elastic modulus E A vacuum suction member of Example 14 was produced in the same manner as in Example 2 except that it was formed of a silicone resin having a hardness of 20 and a pressure of 4 MPa.

(Example 15)
The diameter φ of each of the first element 1221 and the second element 1222 is 0.5 mm, the density of the designated outer convex portion 122 is 1.61%, and the second element 1222 has an elastic modulus E The vacuum suction member of Example 15 was produced in the same manner as in Example 5 except that it was formed of a fluorine resin (FPA) of 350 [MPa].

(Example 16)
The vacuum suction member of Example 16 was produced in the same manner as in Example 15 except that the diameter φ of each of the first element 1221 and the second element 1222 was 1.0 [mm].

(Example 17)
The diameter φ of each of the first element 1221 and the second element 1222 was 0.5 [mm], and the second element 1222 was formed of a polyimide resin having an elastic modulus E of 3000 [MPa]. The length L (height H ₂₂ ) of the second element 1222 is 7.0 × 10 ⁻⁵ [m]. The density of the designated outer convex portion 122 was set to 0.80% by adjusting the grating pitch. A vacuum suction member of Example 17 was manufactured in the same manner as Example 1 except for these.

(Comparative example)
(Comparative example 1)
The vacuum suction member of Comparative Example 1 was produced in the same manner as in Example 14 except that the diameter φ of each of the first element 1221 and the second element 1222 was 1.0 [mm].

(Comparative example 2)
The diameter φ of each of the first element 1221 and the second element 1222 is 1.0 [mm], and the length L (height H ₂₂ ) of the second element 1222 is 1.0 × 10 ⁻⁵ [m]. A vacuum suction member of Comparative Example 2 was produced in the same manner as Example 15 except for the above.

(Comparative example 3)
The diameter φ of each of the first element 1221 and the second element 1222 is 1.0 [mm], the density of the designated outer convex portion 122 is set to 3.22%, and the length L of the second element 1222 A vacuum suction member of Comparative Example 3 was produced in the same manner as in Example 17 ^except that the (height H ₂₂ ) was 2.0 × 10 ⁻⁵ [m].

(Evaluation)
A substrate W (silicon wafer) with a diameter of 300 mm and a thickness of 0.7 mm was placed on the main surface 102 side of the base 1 of the vacuum suction member of each of the example and the comparative example. The maximum value of the PV value of the flatness (local flatness) of the surface W ₁ of the substrate W (local flatness) 20 [mm] x 20 [mm] measured using a non-contact type laser interferometer (GPI Hs manufactured by ZYGO) It was 0.5 μm. Thereafter, the space sandwiched by the back surface W ₂ of the substrate W and the main surface 102 of the base 1 was depressurized by the vacuum suction device through the ventilation path 20. Thus, the substrate W was held by the vacuum suction member. In this state, PV value of the surface W ₁ of the substrate W 20 [mm] × 20 [ mm] was measured using a laser interferometer of the non-contact type.

  These measurement results are shown together in Table 1 together with the characteristic design items of the designated outer convex portion 122.

From Table 1, according to the vacuum suction member of each Example, it can be seen that the improvement in the overall flatness of the surface W ₁ of the substrate W is achieved than vacuum suction member of each comparative example.

1. base body 10. convex portion 11. inner convex portion group 12. outer convex portion group 14. annular convex portion 20 ventilating path 102 main surface of base 104 concave portion 112 inner convex portion , 122 .. outer protrusion (designated outer protrusion), 202 .. opening, 1120 .. end surface of inner protrusion, 1220 .. end surface of outer protrusion, 1221 .. first element, 1222 .. second element, S ₁ .. main Substrate inner area, S ₂ .. Principal surface outer area, W .. Substrate (wafer), W ₁ .. Substrate surface, W ₂ .. Substrate back surface, X ₁ .. Substrate inner area, X ₂ .. Substrate outer area.

Claims (6)

A substrate,
A plurality of projections projecting from the main surface of the substrate;
A vacuum suction path having an opening in the main surface of the substrate passing through the inside of the substrate;
The plurality of convex portions are an inner convex group arranged in an inner area on the main surface of the base, and an outer convex group arranged in an annular outer area surrounding the inner area on the main surface of the base And consists of
The end surface position based on the main surface of the above-mentioned base of each of a plurality of specified outside convex parts which constitute at least one copy among the above-mentioned outside convex part group is each of a plurality of inner convex parts which constitute the above-mentioned inner convex part group. And a part of each of the plurality of designated outer convex parts is made of an elastic material having a lower elastic modulus than the remaining part. Vacuum suction member to be. In the vacuum suction member according to claim 1,
Each of the plurality of designated outer protrusions is a first element protruding from the main surface of the base, and a second element formed of the elastic material continuously provided on the end face of the first element. And
An end surface position based on the main surface of the base of the second element is higher than an end surface position based on the main surface of the base of each of the plurality of inner protrusions. In the vacuum suction member according to claim 1 or 2,
The elastic modulus E [Pa] of the elastic material, the length L [m] of the elastic material in the direction perpendicular to the main surface of the base, and the cross-sectional area S [in elastic cross section parallel to the main surface of the base Vacuum adsorption member characterized in that m ² ] satisfies the conditions represented by 4 [MPa] ≦ E and 1.0 × 10 ⁻⁷ ≦ L / (E × S) ≦ 5.0 × 10 ^−6. . In the vacuum suction member according to claim 1,
Each of the plurality of designated outer protrusions is a first element configured separately from the base, and the elastic element supporting the first element at an end while being supported by the base And a second element being configured;
A vacuum suction member characterized in that an end surface position of the first element is higher than an end surface position of each of the plurality of inner convex portions. In the vacuum suction member according to claim 4,
The semiconductor device further comprises a recess recessed from the main surface of the base,
The first element is partially displaceably inserted in the recess, and the second element is accommodated in the recess and supported by the bottom of the recess. Vacuum suction member characterized by In the vacuum suction member according to any one of claims 1 to 5,
An annular convex portion protruding from the main surface of the base body is further provided to surround each of the plurality of convex portions,
The end surface position of the annular convex portion based on the main surface of the base is lower than the end surface position based on the main surface of the base of each of the plurality of designated outer convex portions or the plurality of designated outer convex portions The vacuum suction member characterized in that it is the same as the end face position based on the main surface of each of the substrates.