JP6960293B2 - Board holding member - Google Patents

Description

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

A technique has been proposed in which a steel ball holding frame for supporting a wafer is mounted in a recess of the chuck body in a ball contact type wafer chuck (board holding member) in which the steel balls can be replaced. (See Patent Document 1). By reducing the pressure through the vacuum passage provided in the chuck body, the wafer is attracted and supported by the steel ball and the seal ring provided in the chuck body.

Tokushu Kohei 06-097674

However, when the substrate is repeatedly adsorbed by the substrate holding member, the support member that supports the substrate and the substrate slide during adsorption, and the support member wears. As a result, the flatness of the substrate to be adsorbed deteriorates, and a predetermined process cannot be performed. In that case, it is necessary to modify the surface shape of the vacuum chuck, which causes a problem that the downtime of the apparatus for the substrate process to which the vacuum chuck is attached becomes long and the productivity is lowered.

Therefore, according to the present invention, by easily replacing or repairing only the member supporting the substrate, the adsorption holding performance that can secure the flatness of the substrate is restored, and the substrate process is used as described above. An object of the present invention is to provide a substrate holding member capable of reducing downtime in an apparatus.

The substrate holding member of the present invention is provided on a substrate having a main surface, one or more first air passages provided on the substrate and having a plurality of first openings opened on the main surface, and the substrate. The second air passage having a second opening that opens on the main surface and the plurality of first openings are each closed at least partially, and at least a part thereof protrudes from the main surface. It is characterized by including a plurality of support members that are detachably arranged with respect to the substrate.

According to the substrate holding member having this configuration, a plurality of support members are arranged so that each of the plurality of first openings is at least partially closed on the main surface of the substrate and at least a part thereof protrudes from the main surface. Will be done. In this state, when the pressure in the first air passage is reduced, a vacuum suction force acts on each of the plurality of support members through the first opening, and each of the plurality of support members is attracted to the substrate. NS. Further, by placing the substrate on the main surface side of the substrate, the substrate comes into contact with at least a part of the plurality of support members. In this state, the pressure of the second air passage is reduced, so that the space sandwiched between the main surface of the substrate and the back surface of the substrate is decompressed through the second opening, and the vacuum suction force toward the main surface of the substrate with respect to the substrate is reduced. Acts, and the substrate is attracted and held by the substrate holding member in a state of being supported by a plurality of supporting members.

When the second air passage is released from the decompressed state (for example, returned to atmospheric pressure), the space sandwiched between the main surface of the substrate and the back surface of the substrate is also released from the decompressed state, and the substrate is removed from the substrate holding member. .. When the first air passage is released from the reduced pressure state (for example, returned to atmospheric pressure), each of the plurality of support members is released from the vacuum suction force and can be removed from the substrate. Therefore, when at least a part of the support members among the plurality of support members is worn or damaged, the substrate is flattened by easily replacing or repairing only at least a part of the support members, not the entire substrate holding member. The suction holding performance is restored so that the degree is ensured, and the downtime of the device for performing the process on the substrate can be shortened.

Each of the plurality of support members is partially housed in the first opening, and covers the entire circumference at a corner between an inner surface of the base and a main surface of the base that defines the first opening. It is preferable that the first opening is closed in a state of contact.

According to the substrate holding member having this configuration, when the pressure in the first air passage is reduced, a vacuum suction force acts on each of the plurality of support members through the first opening and is attracted to the substrate. Since each support member is partially housed in the first opening and is in contact with the corner portion between the inner surface of the substrate defining the first opening and the main surface of the substrate over the entire circumference. Displacement of each support member in the lateral direction is prevented, and the relative position and orientation of each support member with respect to the substrate is more reliably maintained.

It is preferable that the upper end edge portion of the first opening defined by the corner portion is circular, and the support member is a sphere having a diameter larger than that of the upper end edge portion of the first opening portion.

According to the substrate holding member having this configuration, when the first air passage is released from the decompression state, the partially worn support member is replaced, and when the spherical support member is worn, the support member is replaced. The height of the support member protruding from the main surface of the substrate can be restored by rotating the support member so that the worn portion is laterally oriented, for example, without replacing the support member. Even if the support member of the sphere rotates around its center, the relative posture of the support member with respect to the first opening does not change, so that a part of the support member is arranged on the substrate so as to be accommodated in the first opening. The work to be done is facilitated.

Each of the plurality of first openings is composed of a recess defined by a bottom surface recessed from the main surface and a hole portion opened in the bottom surface, and the support member abuts on the bottom surface. It is preferable that a part of the hole is housed in the recess with the hole at least partially closed.

According to the substrate holding member having the above configuration, by reducing the pressure in the first air passage, a vacuum suction force acts on each of the plurality of support members through the holes forming the first opening, so that a plurality of support members are subjected to vacuum suction force. When each of the support members is attracted to the substrate, each support member is partially accommodated in the recess, so that lateral displacement is suppressed by the inner side surface or side portion forming the recess, and the support member is suppressed with respect to the substrate. The relative position and orientation of each support member can be reliably maintained.

The support member has a lower element in which at least a part thereof is housed in a state where the lower end surface is in contact with the bottom surface defining the concave portion, and the lower element projects upward from the upper end surface of the lower element. It is preferably composed of an upper element having an upper end surface having a smaller area than the lower end surface of the above.

According to the substrate holding member having this configuration, when the pressure in the first air passage is reduced, the vacuum suction force acting on the lower end surface of the lower element constituting the support member is increased through the hole of the first opening. Therefore, the position and orientation of the support member with respect to the substrate are reliably maintained. In addition to this, the contact area between the upper end surface of the upper element constituting the support member and the back surface of the substrate can be reduced.

Each of the plurality of recesses has a shape of being recessed in a columnar shape from the main surface, and the support member is formed by the columnar lower element and the columnar upper element having a diameter smaller than that of the lower element. It is preferably configured.

According to the substrate holding member having this configuration, even if the columnar lower element constituting the support member rotates around its central axis, the relative posture of the lower element with respect to the first opening does not change, so that the support member The work of arranging the lower element of the substrate on the substrate so that at least a part of the lower element is accommodated in the first opening is facilitated.

The substrate holding member of the present invention is provided on the substrate, extends in an annular shape so as to surround the plurality of first openings and the second openings on the main surface, and the plurality of members extend from the main surface. It is preferable that the annular convex portion is further provided so as to project from the main surface at the same height as each of the support members or at a lower height than each of the plurality of support members.

According to the substrate holding member having this configuration, the space where the upper and lower sides are defined by the main surface of the substrate and the back surface of the substrate and the peripheral edge is defined by the annular convex portion is decompressed through the second opening of the second air passage. When this is done, it becomes easy to improve and maintain the vacuum suction force acting on the substrate toward the main surface of the substrate.

Top view of the substrate holding member as the first embodiment of the present invention. The vertical sectional view of the substrate holding member along the line IIA-IIA of FIG. The vertical sectional view of the substrate holding member along the line IIB-IIB of FIG. The vertical sectional view corresponding to FIG. 2A of the substrate holding member as the 2nd Embodiment of this invention. The vertical sectional view corresponding to FIG. 2B of the substrate holding member as the 2nd Embodiment of this invention.

(First Embodiment)
(composition)
The substrate holding member as the first embodiment of the present invention shown in FIGS. 1, 2A and 2B includes a substrate 1, a plurality of support members 12, an annular convex portion 14, and a first air passage 21. , A second vent passage 22 and the like.

The substrate 1 is formed of a ceramic sintered body such as SiC, AlN, and Al ₂ O _{3, and has a flat main surface 10.} The main surface 10 does not form a support surface for the substrate W. The main surface 10 is not flat and may be a concave curved surface or a convex curved surface. The first air passage 21 extends from the side surface of the substrate 1 in parallel with the main surface 10 and inside the substrate 1 so as to extend from the parallel extending portion toward the main surface 10. It has a plurality of first openings 210 that are formed and open on the main surface 10. The second ventilation passage 22 extends inside the substrate 1 so as to extend from the side surface of the substrate 1 in parallel with the main surface 10 and from the portion extending in parallel toward the main surface 10. It has a plurality of second openings 220 that are formed and open on the main surface 10.

In the present embodiment, the first opening 210 is recessed from the recess 211 (cylindrical counterbore portion) recessed from the main surface 10 of the substrate 1 in a columnar shape and from the main surface 10 of the substrate 1 defining the recess 211. It is composed of a hole 212 that opens to the bottom surface. The corners formed between the inner surface of the substrate 1 defining the first opening 210 (or the recess 211 constituting the opening 210) and the main surface 10 of the substrate 1 are chamfered. The first opening 210 is a plurality (for example, four) separated from each other on the main surface 10 of the substrate 1 for each of a center and a plurality of directions (for example, eight directions) constituting one direction group with respect to the center. Is arranged at each of the positions of, and at each of a plurality of (for example, two) positions separated from each of a plurality of directions (for example, eight directions) constituting another direction group different from the one direction group. There is. The plurality of first openings 210 are arranged so as to have rotational symmetry (for example, eight-fold symmetry) with respect to the center. The portion of the first air passage 21 extending parallel to the main surface 10 has a plurality of concentric annular portions and the plurality of annular portions in accordance with the positions of the plurality of first openings 210. It has a portion extending in the radial direction of the substrate 1 to be communicated with.

The second opening 220 is located at a plurality of (for example, four) positions on the main surface 10 of the substrate 1 that are separated from each other in a direction different from the plurality of directions in which the first opening 210 is arranged with respect to the center. Is located in. In the portion of the second air passage 22 extending parallel to the main surface 10, the plurality of second openings 220 are arranged from the center of the substrate 1 in accordance with the positions of the plurality of second openings 220. It has a part that extends in the direction.

Each of the first vent 21 and the second vent 22 is connected to a separate or common vacuum suction device. It is not necessary for all of the plurality of first openings 210 to form one first air passage 21, and each of the plurality of first openings groups consisting of one or more first openings 210 are independent of each other. Each of the plurality of first ventilation passages may be configured. Similarly, it is not necessary for all of the plurality of second openings 220 to form one second air passage 22, and each of the plurality of second openings groups consisting of one or more second openings 220 , Each of a plurality of separate and independent second air passages may be configured.

The support member 12 is formed of a ceramic sintered body such as SiC, AlN, or Al ₂ O _3. The ceramics sintered body constituting the support member 12 and the ceramics sintered body constituting the substrate 1 may have the same or different main components. Each of the plurality of support members 12 is arranged with respect to the substrate 1 so as to at least partially close each of the plurality of first openings 210 and at least a part of the support members 12 project from the main surface 10 at the same height. NS. The support member 12 is a removable member separate from the substrate 1.

In the present embodiment, the support member 12 is a sphere having a diameter larger than that of the upper end edge portion defined by the corner portions of the substrate 1 described above. That is, the support member 12 is partially housed in the recess 211 of the first opening 210, and closes the first opening 210 by abutting the corner portion chamfered as described above over the entire circumference. There is. Although the support member 12 is separated from the bottom surface defining the recess 211 of the first opening 210, the support member 12 comes into contact with the bottom surface defining the recess 211 of the first opening 210, so that the base 1 is formed. The height of the upper end surface or the upper end portion of the support member 12 with respect to the main surface 10 may be determined.

The annular convex portion 14 is provided on the substrate 1, extends in an annular shape so as to surround the plurality of first openings 210 and second openings 220 on the main surface 10 (see FIG. 1), and extends from the main surface 10 in an annular shape. It protrudes at the same height as each of the plurality of support members 12. The vertical cross-sectional shape of the annular convex portion 14 may have various shapes such as a rectangular shape, a trapezoidal shape, a triangular shape, and a semicircular shape. The annular convex portion 14 is formed by cutting, blasting, laser machining, or a combination thereof. The height (upper end surface position) of the annular convex portion 14 may be lower than each of the plurality of support members 12 from the main surface 10.

(function)
According to the substrate holding member as the first embodiment of the present invention, each of the plurality of first openings 210 is at least partially closed on the main surface 10 of the substrate 1, and at least a part thereof is the same from the main surface 10. A plurality of support members 12 are arranged so as to project at a height (see FIGS. 2A and 2B). Since the support member 12 is a sphere and the relative posture of the support member 12 with respect to the first opening 210 does not change even if the support member 12 is rotated around the center thereof, a part of the support member 12 is housed in the first opening 210. The work of arranging the substrate 1 is facilitated.

In this state, the pressure of the first air passage 21 is reduced, so that a vacuum suction force acts on each of the plurality of support members 12 through the first opening 210 and is attracted to the substrate 1. Each of the plurality of spherical support members 12 is partially housed in the first opening 210 having a diameter smaller than this, and is in contact with the corner portion of the substrate 1 over the entire circumference. 1 Each of the openings 210 is closed. Therefore, the support member 12 is prevented from being displaced laterally with respect to the first opening 210, and the relative position and orientation of each support member 12 with respect to the substrate 1 is more reliably maintained.

Further, by placing the substrate W on the main surface 10 side of the substrate 1, the back surface of the substrate W comes into contact with at least a part of the upper end surface or the upper end portion of the plurality of support members 12. In this state, the pressure of the second ventilation passage 22 is reduced, so that the space sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W through the second opening 220 and surrounded by the annular convex portion 14 is decompressed. Then, a vacuum suction force toward the main surface of the substrate 1 acts on the substrate W, and the substrate W comes into contact with all of the plurality of support members 12 and is attracted and held by the substrate holding member in a flat state.

When the second ventilation passage 22 is released from the decompressed state (for example, returned to atmospheric pressure), the space sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W is also released from the decompressed state, and the substrate W is released from the decompressed state. It is removed from the holding member. When the first air passage 21 is released from the reduced pressure state (for example, returned to atmospheric pressure), each of the plurality of support members 12 which are members separate from the base 1 is released from the vacuum suction force and is released from the base 1. It becomes removable.

Therefore, when at least a part of the support members 12 among the plurality of support members 12 is worn, only at least a part of the support members 12 is easily replaced or repaired, not the entire substrate holding member. The suction holding performance is restored so that the flatness of the substrate W is ensured, and the downtime of the apparatus for performing the process on the substrate W can be shortened. Further, by rotating the support member 12 which is a sphere so that the worn portion is oriented sideways, for example, the protruding heights of the plurality of support members 12 from the main surface 10 of the substrate 1 can be restored.

(Second Embodiment)
(composition)
In the substrate holding member as the second embodiment of the present invention shown in FIGS. 3A and 3B, the support member 120 abuts on the bottom surface of the substrate 1 defining the recess 211 constituting the first opening 210. The hole 212 is configured to be partially housed in the recess 211 with the hole 212 at least partially closed.

More specifically, the support member 120 has a columnar lower element 121 in which at least a part of the support member 120 is housed in the recess 211 in a state where the lower end surface is in contact with the bottom surface of the substrate 1 defining the recess 211, and a lower portion. It is composed of a columnar upper element 122 that protrudes upward from the upper end surface of the element 121 and has an upper end surface having a smaller area than the lower end surface of the lower element 121.

In the present embodiment, the columnar lower element 121 has a diameter smaller than the inner diameter of the inner surface of the base 1 that defines the recess 211, and is between the side surface of the lower element 121 and the inner surface that defines the recess 211 by that amount. There is a gap. The columnar lower element 121 has a larger diameter than the hole 212. Therefore, the first opening 210 or all the holes 212 forming the first opening 210 are closed by the support member 120 or the lower end surface of the lower element 121 constituting the support member 120.

Since the configuration of the substrate holding device other than the above is the same as that of the first embodiment, the same reference numerals are used and the description thereof will be omitted.

(function)
According to the substrate holding member as the second embodiment of the present invention, each of the plurality of first openings 210 is at least partially closed on the main surface 10 of the substrate 1, and at least a part thereof is the same from the main surface 10. A plurality of support members 120 are arranged so as to project at a height (see FIGS. 3A and 3B). Even if the columnar lower element 121 constituting the support member 120 rotates around its central axis, the relative posture of the lower element 121 with respect to the first opening 210 does not change, so that the lower element 121 of the support member 120 The work of arranging the substrate 1 so that at least a part thereof is accommodated in the recess 211 of the first opening 210 can be facilitated.

In this state, the pressure of the first air passage 21 is reduced, so that a vacuum suction force acts on each of the plurality of support members 120 through the first opening 210, and each of the plurality of support members 120 is a substrate 1. Is adsorbed against. The lower end surface of the columnar lower element 121 constituting the support member 120 closes each of the plurality of first openings 210 having a smaller diameter. At this time, the lateral displacement of the support member 120 with respect to the first opening 210 is suppressed by the inner surface defining the recess 211, and the relative position and posture of each support member 120 with respect to the substrate 1 is ensured. Be maintained.

Further, by placing the substrate W on the main surface 10 side of the substrate 1, the back surface of the substrate W is placed on the upper end surface or the upper end portion of at least a part of the plurality of support members 120 or the upper elements 122 constituting the support member 120. Contact. In this state, the pressure of the second ventilation passage 22 is reduced, so that the space sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W through the second opening 220 and surrounded by the annular convex portion 14 is decompressed. Then, a vacuum suction force toward the main surface of the substrate 1 acts on the substrate W, and the substrate W comes into contact with all of the plurality of support members 120 and is attracted and held by the substrate holding member in a flat state.

Since the area of the upper end surface of the upper element 122 is smaller than the area of the lower end surface of the lower element 121 constituting the support member 120, the hole 212 of the first opening 210 when the first air passage 21 is depressurized. Through this, the vacuum suction force acting on the lower end surface of the lower element 121 constituting the support member 120 is increased, so that the position and orientation of the support member 120 with respect to the substrate 1 are surely maintained. In addition to this, the contact area between the upper end surface of the upper element 122 constituting the support member 120 and the back surface of the substrate W can be reduced.

When the second ventilation passage 22 is released from the decompressed state (for example, returned to atmospheric pressure), the space sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W is also released from the decompressed state, and the substrate W is released from the decompressed state. It is removed from the holding member. When the first air passage 21 is released from the reduced pressure state (for example, returned to atmospheric pressure), each of the plurality of support members 120, which are members separate from the base 1, is released from the vacuum suction force and is released from the base 1. It becomes removable.

Therefore, when at least a part of the support members 120 out of the plurality of support members 120 is worn or damaged, only at least a part of the support members 120 is replaced or repaired instead of the entire substrate holding member, so that the substrate W is replaced or repaired. The suction holding performance that ensures flatness is restored, and the downtime of the device for performing the process on the substrate W can be shortened.

(Other Embodiments of the present invention)
In the first embodiment, the upper end edge of the first opening 210 defined by the corners between the inner surface of the substrate 1 and the main surface 10 is circular, and the support member 12 is spherical, but the support The shapes and sizes of the support member 12 and the upper end edge of the first opening 210 may be designed in various forms so that the member 12 abuts on the corners of the substrate 1 over the entire circumference. For example, the upper end edge of the first opening 210 may be formed in a circular shape, and the lower portion of the support member 12 may be formed in a spherical shape, an elliptical spherical shape, a downward conical shape, a downward conical cone shape, or the like. Further, the upper end edge of the first opening 210 may be formed in a rectangular shape, and the lower portion of the support member 12 may be formed in a downward quadrangular pyramid shape, a downward quadrangular pyramid shape, or the like. It is preferable that the corners of the substrate 1 are chamfered (C chamfering / R chamfering).

In the first embodiment, the shapes of the support member 12 and the upper end edge of the first opening 210 are changed so that the support member 12 abuts on the corner portion of the substrate 1 in a part in the circumferential direction. May be good. For example, the upper end edge of the first opening 210 is formed in a front-rear circular shape, the lower portion of the support member 12 has a spherical shape or a semi-elliptical spherical shape having a diameter larger than the rear circle, and the bottom surface has a diameter larger than the rear circle. It may be formed in a downward conical shape or a downward conical trapezoidal shape.

In the second embodiment, both the lower element 121 and the upper element 122 constituting the support member 120 are formed in a columnar shape, but they may be formed in various other shapes. For example, the lower element 121 may be formed in a columnar shape, and the upper element 122 may be formed in a truncated cone shape or a truncated cone shape in which the upper end surface and the bottom surface of the lower element 121 are shared.

In the second embodiment, the area of the upper end surface of the upper element 122 is designed to be smaller than the area of the lower end surface of the lower element 121 constituting the support member 120, but the area of the upper element 122 is smaller than the area of the lower end surface of the lower element 121. The area of the upper end surface may be designed to be large, or the area of the lower end surface of the lower element 121 and the area of the upper end surface of the upper element 122 may be designed to be the same. For example, the support member 120 may be formed in a columnar or cylindrical shape without distinguishing between the lower element 121 and the upper element 122.

In the second embodiment, each shape and size of the support member 120 may be designed in various forms so that the support member 120 closes all of the holes 212 constituting the first opening 210. For example, the support member 120 is formed in a shape such as an upward cone, a pyramid, a cone, a cone, a stepped cone, or a cone, and the bottom surface or the bottom surface thereof covers the entire hole 212. The size may be designed to block. In the second embodiment, each shape and size of the support member 12 may be designed in various forms so that the support member 120 closes a part of the hole 212 forming the first opening 210. For example, the support member 12 is formed in an upward conical shape, a pyramidal shape, a truncated cone shape, a truncated cone shape, or the like, and is sized so as to close only a part of the hole 212 by reducing the area of the bottom surface or the lower bottom surface. May be designed.

In the substrate holding member of the embodiment, the annular convex portion 14 in the substrate 1 may be omitted. In the substrate holding member of the above embodiment, the protrusion heights (upper end points or upper end surface height positions) of the plurality of support members 12 and 120 from the main surface 10 of the substrate 1 are all the same, but some of them are the same. The protruding height of the protruding members 12 and 120 from the main surface 10 of the base 1 may be different from the protruding height of the other protruding members 12 and 120 from the main surface 10 of the base 1.

In the substrate holding member of the above embodiment, the protruding height of the annular convex portion 14 from the main surface 10 of the substrate 1 was the same as the protruding height of the plurality of support members 12 and 120 from the main surface 10 of the substrate 1. However, the protruding height of the annular convex portion 14 from the main surface 10 of the base 1 may be lower than the protruding height of the plurality of support members 12 and 120 from the main surface 10 of the base 1. At this time, the annular convex portion 14 is sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W, and is high enough to secure a pressure difference of 50 kPa or more between the space surrounded by the annular convex portion 14 and the atmosphere. It is preferable to adjust to. When the protruding height of the annular convex portion 14 is made lower than the protruding height of the support members 12 and 120, the contact area between the substrate W and the substrate 1 is reduced by the amount that the contact between the annular convex portion 14 and the substrate W is avoided. , It is possible to suppress the generation of particles resulting from the contact of the substrate 1 with the substrate W.

In the substrate holding member of the above embodiment, the support members _{12 and} 120 _{were ceramic sintered bodies such as SiC, AlN, and A 2 lO 3} , but the materials constituting the support members 12 and 120 were polyimide and PTFE ( It may be a synthetic resin such as polytetrafluoroethylene) or PEEK (polyetheretherketone), a metal, or quartz glass. When the support members 12 and 120 are made of synthetic resin, chemical contamination can be suppressed as compared with the case where the support members 12 and 120 are ceramic sintered bodies.

(Example)
(Example 1)
The substrate holding device of Example 1 was manufactured according to the first embodiment of the present invention shown in FIGS. 1, 2A and 2B. A substrate 1 made of a substantially disk-shaped SiC ceramic sintered body having an outer diameter of φ300 mm and a thickness of 7 mm was produced. A substantially cylindrical recess 211 having a diameter of 1.5 mm and a depth of 2.0 mm from the main surface 10 of the substrate 1 and a substantially cylindrical recess 211 having a diameter of 1.0 mm and a depth of 3.0 mm from the main surface 10 of the substrate 1. A first opening 210 having a hole 212 and a substantially columnar second opening 220 having a diameter of 2.0 mm and a depth of 5.0 mm from the main surface 10 of the substrate 1 were formed. A plurality of support members 12 made of a substantially spherical alumina sintered body having a diameter of 4 mm were produced. An annular convex portion 14 having a substantially rectangular vertical cross-sectional shape having an outer diameter of φ299 mm, a width of 0.5 mm, and a height of 500 μm was formed on the peripheral edge of the main surface 10 of the substrate 1. When the corner portion between the main surface 10 of the base 1 and the inner surface of the base 1 defining the first opening 210 is chamfered so that the spherical support member 12 is brought into contact with the corner portion. , The height of the support member 12 was adjusted to be the same as the height of the annular convex portion 14.

After placing the silicon wafer as the substrate W on the main surface 10 side of the substrate 1, the first ventilation passage 21 and the second ventilation passage 22 are sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W by the vacuum suction device. Moreover, the pressure was reduced until the differential pressure between the space surrounded by the annular convex portion 14 and the atmosphere became 85 kPa. As a result, the substrate W was attracted and held by the flat surfaces formed on the upper end surfaces of the annular convex portion 14 and the support member 12. In this state, the flatness of the substrate W was measured with a laser interferometer (GPI Hs manufactured by ZYGO). The measurement result of the entire substrate W was 3.1 μm in PV value, and it was confirmed that the substrate W could be adsorbed and held by the substrate holding member while sufficient flatness was secured.

(Example 2)
The substrate holding device of Example 2 was manufactured according to the second embodiment of the present invention shown in FIGS. 3A and 3B. A substrate 1 made of a substantially disk-shaped SiC ceramic sintered body having an outer diameter of φ300 mm and a thickness of 7 mm was produced. A substantially cylindrical recess 211 having a diameter of 4.0 mm and a depth of 3.0 mm from the main surface 10 of the substrate 1 and a substantially cylindrical recess 211 having a diameter of 1.0 mm and a depth of 3.0 mm from the main surface 10 of the substrate 1. A hole 212 and a substantially columnar second opening 220 having a diameter of 2.0 mm and a depth of 5.0 mm from the main surface 10 of the substrate 1 were formed. A plurality of alumina sintered bodies composed of a substantially cylindrical lower element 121 having an outer diameter of φ3.9 mm and a height of 2.6 mm and a substantially cylindrical upper element 122 having an outer diameter of φ0.5 mm and a height of 0.5 mm. The support member 120 of the above was manufactured. An annular convex portion 14 having a substantially rectangular vertical cross-sectional shape having an outer diameter of φ299 mm, a width of 0.5 mm, and a height of 100 μm was formed on the peripheral edge of the main surface 10 of the substrate 1.

After placing a silicon wafer as the substrate W on the main surface 10 side of the substrate 1, the first ventilation passage 21 and the second ventilation passage 22 are sandwiched between the main surface 10 of the substrate 1 and the back surface of the substrate W by a vacuum suction device. Moreover, the pressure was reduced until the differential pressure between the space surrounded by the annular convex portion 14 and the atmosphere became 80 kPa. As a result, the substrate W was attracted and held by the flat surfaces formed on the upper end surfaces of the annular convex portion 14 and the support member 12. In this state, the flatness of the substrate W was measured with a laser interferometer (GPI Hs manufactured by ZYGO). The measurement result of the entire substrate W was 4.8 μm in PV value, and it was confirmed that the substrate W could be adsorbed and held by the substrate holding member while sufficient flatness was secured.

1-base, 10-main surface, 12, 120-support member, 14-annular convex portion, 21-first ventilation path, 22-second ventilation path, 121-lower element, 122-upper element, 210-first Opening, 211, concave, 212, hole, 220, second opening, W. Substrate (wafer).

Claims (7)

A substrate with a main surface and
One or more first vents provided on the substrate and having a plurality of first openings that open on the main surface.
A second vent that is provided on the substrate and has a second opening that opens on the main surface.
Provided with a plurality of support members that are at least partially closed to each of the plurality of first openings and that are detachably arranged with respect to the substrate so that at least a part thereof protrudes from the main surface. A substrate holding member characterized by being present. Each of the plurality of support members is partially housed in the first opening, and covers the entire circumference at a corner between an inner surface of the base and a main surface of the base that defines the first opening. The substrate holding member according to claim 1, wherein the first opening is closed in a state of being in contact with the first opening. The upper end edge of the first opening defined by the corner is circular.
The substrate holding member according to claim 2, wherein the support member is a sphere having a diameter larger than that of the upper end edge portion of the first opening. Each of the plurality of first openings is composed of a recess defined by a bottom surface recessed from the main surface and a hole portion opened in the bottom surface.
The substrate holding member according to claim 1, wherein the support member is partially housed in the recess in a state of being in contact with the bottom surface and at least partially closing the hole. The support member has a lower element in which at least a part of the lower element is housed in a state where the lower end surface is in contact with the bottom surface defining the concave portion, and the lower element projects upward from the upper end surface of the lower element. The substrate holding member according to claim 4, further comprising an upper element having an upper end surface having an area smaller than that of the lower end surface of the above. Each of the plurality of recesses has a shape of being recessed in a columnar shape from the main surface.
The substrate holding member according to claim 5, wherein the support member is composed of the columnar lower element and the columnar upper element having a diameter smaller than that of the lower element. It is provided on the substrate, extends in an annular shape on the main surface so as to surround the plurality of first openings and the second opening, and has the same height as each of the plurality of support members from the main surface. The substrate holding member according to any one of claims 1 to 6, further comprising an annular convex portion protruding from the main surface at a height lower than that of each of the plurality of support members. ..

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