Support structure for disk-shaped substrate

Abstract

A support structure (1) for a disk-shaped substrate (D) is provided with a support part (20) having a support surface that: is disposed around a vertically-extending center line (C1); is inclined downward toward the center line (C1); and abuts against the circumferential part (D1) of the disk-shaped substrate (D) from below to support the self-weight of the disk-shaped substrate (D).

Description

Support structure for disk-shaped substrate

[0001] The present invention relates to a support structure for a disk-shaped substrate.

[0002] Conventionally, in the manufacturing process of semiconductor wafers (disk-shaped substrates), a mechanism for supporting the wafer is required for transporting the wafer. One example of a wafer support mechanism is a mechanism for holding the peripheral portion of the wafer, the so-called edge portion, which is the portion not targeted for device manufacturing.

[0003] For example, Patent Document 1 discloses an aligner device having a fixed stage on which a wafer is placed, multiple grippers for gripping the edges of the wafer, and a gripping mechanism that moves each gripper toward the center of the wafer. In the aligner device disclosed in Patent Document 1, the gripping mechanism moves each gripper toward the center of the wafer so that each gripper engages with the edge of the wafer placed on the fixed stage. This holds the wafer.

[0004] Japanese Patent Application Laid-Open No. 2003-243294

[0005] The technique described in Patent Document 1 requires a gripping mechanism that moves the gripping parts closer to the center of the wafer, which makes the aligner device configuration complex.

[0006] Furthermore, in the above-mentioned technology, the wafer is held by each gripper applying force to the edge of the wafer, which may result in excessive force being applied to the edge of the wafer, which may damage the edge.

[0007] The object of the present invention has been made in consideration of the above-mentioned problems, and is to provide a support structure for a disk-shaped substrate that is capable of supporting a disk-shaped substrate with a simple configuration and that can prevent damage to the disk-shaped substrate.

[0008] The present invention provides a support structure for supporting a disk-shaped substrate, comprising a support part having a support surface arranged around a center line extending in a vertical direction and inclined downward toward the center line, the support surface abutting the circumferential portion of the disk-shaped substrate from below to support the weight of the disk-shaped substrate.

[0009] Fig. 1 is a cross-sectional view of a support structure according to one embodiment of the present invention. Fig. 2 is an enlarged side view of a disk-shaped substrate according to one embodiment of the present invention. Fig. 3 is a top view of the periphery of a support portion of a support structure according to one embodiment of the present invention. Fig. 4 is a top view of a main body portion of a support structure according to one embodiment of the present invention. Fig. 5 is a cross-sectional view of the main body portion of a support structure according to one embodiment of the present invention. Fig. 6 is an enlarged cross-sectional view of region VI of Fig. 5.

[0010] A support structure 1 according to one embodiment of the present invention will be described below with reference to the drawings. Fig. 1 is a cross-sectional view of the support structure 1. Fig. 2 is an enlarged side view of a disk-shaped substrate D. Note that, hereinafter, the Z direction in each figure will be referred to as the up-down direction, and in particular, the +Z direction will be referred to as the up-down direction and the -Z direction will be referred to as the down-down direction.

[0011] The support structure 1 according to this embodiment supports a disk-shaped substrate D that is transported in a predetermined direction (here, the X direction).

[0012] Referring to FIG. 2 , the disk-shaped substrate D according to this embodiment will be described. The disk-shaped substrate D is, for example, a silicon wafer, which is a raw material for semiconductor chips. The disk-shaped substrate D has, on its circumferential portion D1, an upper inclined surface facing upward and a lower inclined surface D11 (an example of a supported surface) facing downward. The upper inclined surface is a flat surface that slopes upward (as it approaches) toward the center O of the disk-shaped substrate D. The lower inclined surface D11 is a flat surface that slopes downward (as it approaches) toward the center O of the disk-shaped substrate D. In this embodiment, the lower inclined surface inclination angle θ1 of the disk-shaped substrate D is set to 22.5°. The lower inclined surface inclination angle θ1 is the exterior angle formed by the lower inclined surface D11 and a functional surface D12 used in device manufacturing, which intersects with the lower inclined surface D11. The upper inclined surface and the lower inclined surface D11 are formed by chamfering the circumferential portion D1.

[0013] As shown in FIG. 1, the support structure 1 has a table unit 10, a support portion 20 that is removably fixed to the table unit 10 and supports a disk-shaped substrate D, and a transport mechanism 40 that transports the table unit 10 in the X direction.

[0014] The table unit 10 raises, lowers, and rotates the disk-shaped substrate D supported by the support portion 20. The table unit 10 has a table main body 11, a weight portion 12, a table support portion 13, a drive portion 14, and a casing 15.

[0015] Figure 3 is a top view of the support portion 20 and its surroundings of the support structure 1. The table body 11 is a rotary table having a circular plate shape and capable of rotating around a center line C1. The table body 11 has an upper surface facing upward, to which the support portion 20 and the weight portion 12 are detachably fixed. Note that the weight portion 12 is not shown on the left side of the page in Figure 3.

[0016] The weight portion 12 is disposed on the upper surface of the table body 11 and adjusts the rotational balance of the table body 11. The weight portion 12 is made of a circular flat plate and is fixed to the table body 11 via a plurality of weight fasteners 31. The plurality of weight fasteners 31 are formed, for example, by dowel pins or bolts. As shown in FIG. 3 , the weight portion 12 is provided with a plurality of notches 12A cut out along the radial direction of the table body 11.

[0017] Returning to FIG. 1 , the table support 13 supports the table body 11 in a state in which it can rotate and move up and down. Specifically, the table support 13 has an upper end and a lower end. The upper end is connected to the lower surface of the table body 11, which faces downward. The lower end is connected to the drive unit 14 and is driven by the drive unit 14. The table support 13 passes through the ceiling of the casing 15 and extends in the vertical direction between the table body 11 and the drive unit 14.

[0018] The driving unit 14 is disposed inside the casing 15, and generates a driving force for raising and lowering the table main body 11 and a driving force for rotating the table main body 11. For example, the driving unit 14 includes a servo motor (not shown) and a pneumatic cylinder (not shown).

[0019] The support unit 20 is disposed on the upper surface of the table body 11 around a center line C1 extending in the vertical direction, and horizontally supports the disk-shaped substrate D. As shown in Fig. 3, the support unit 20 according to this embodiment has three support members 200. In other embodiments, the support unit 20 may have two support members 200, or four or more support members 200.

[0020] The three support members 200 are arranged at equal intervals around the center line C1 of the support portion 20 so that the center line C1 and the center O of the disk-shaped substrate D are concentric, and support the disk-shaped substrate D. Specifically, each of the three support members 200 is arranged so that the distance between the center O and each support member 200 is equal in the radial direction of a circle (virtual circle) centered on the center line C1. This configuration allows each support member 200 to support the disk-shaped substrate D horizontally. It is preferable to use a material for each support member 200 that does not scratch or contaminate the disk-shaped substrate D. For example, a resin material such as polyether ether ketone or polyacetal is preferably used.

[0021] Next, the detailed configuration of the three support members 200 will be described with reference to FIGS. 3 to 6. FIG. 4 is a top view of the main body 220 of the support member 200. Specifically, FIG. 4 is a top view of the main body 220 of the support member 200 shown in the upper center of FIG. 3. FIG. 5 is a cross-sectional view of the main body 220. Specifically, FIG. 5 is a cross-sectional view of the main body 220 shown in the upper center of FIG. 3, taken along a cross section including the center line C1. FIG. 6 is an enlarged cross-sectional view of region VI shown in FIG. 5. In this embodiment, the three support members 200 each have the same configuration. Therefore, the following description will focus on the configuration of one support member 200, and descriptions of the remaining support members 200 will be omitted. As shown in FIG. 3, the support member 200 includes a connecting portion 210 and a main body 220 detachably fixed to the connecting portion 210.

[0022] The connection portion 210 is detachably fixed to the table body 11 and supports the body portion 220. Specifically, the connection portion 210 has a connection base portion 211 and an extension portion 212.

[0023] The connection base 211 is disposed in an area surrounded by the cutout 12A on the table body 11. The connection base 211 is fixed to the table body 11 by a plurality of connection base fasteners 32. That is, the connection base 211 is fixed directly to the table body 11 without the weight portion 12 being interposed therebetween. This configuration facilitates removal of the connection base 211 or the weight portion 12 from the table body 11. That is, it is easy to remove the weight portion 12 while the connection base 211 is fixed to the table body 11, and it is easy to remove the connection base 211 while the weight portion 12 is fixed to the table body 11. The plurality of connection base fasteners 32 are, for example, bolts having a head and a shaft (not shown). As shown in FIG. 3 , the plurality of connection base fasteners 32 are arranged in a radial line.

[0024] The extension portion 212 extends radially outward from the connection base portion 211 to support the main body portion 220. Specifically, the extension portion 212 extends from the connection base portion 211 so that its radially outer end portion is positioned radially outward from the outer edge of the table main body 11.

[0025] The main body 220 is detachably fixed to the extension 212, and supports the disk-shaped substrate D. As shown in FIGS.

[0026] The base 221 is fixed to the radially outer end of the extension 212. As shown in FIGS. 4 and 5 , the base 221 is a base having a substantially rectangular parallelepiped shape and has a plurality of base fixing holes H. Each base fixing hole H can communicate with a fixing hole (not shown) formed in the upper part of the extension 212. Each base fixing hole H has a counterbore shape, allowing a base fastener 33 ( FIG. 3 ) to be inserted therethrough in the vertical direction. The base fasteners 33 are, for example, bolts having a head and a shaft. As shown in FIG. 3 , the base fasteners 33 are arranged side by side in the radial direction. Each base fastener 33 passes through the base fixing hole H in the vertical direction and is threaded into the fixing hole, thereby fastening the base 221 and the extension 212 together.

[0027] As shown in FIGS. 4 and 5 , the support 222 is a substantially triangular prism-shaped structure connected to the base 221 and has an upper surface 222a. Specifically, the upper surface 222a is a flat surface facing radially inward of the support 222. The upper surface 222a is disposed around the center line C1 and forms a support surface that abuts against the lower inclined surface D11 of the disk-shaped substrate D from below, supporting the weight of the disk-shaped substrate D. As shown in FIG. 5 , the upper surface 222a is inclined downward toward the center line C1. In this embodiment, the upper surface inclination angle θ2 (see FIG. 5 ) of the upper surface 222a with respect to the radial direction (horizontal plane) is set to be equal to or greater than 15° and equal to or less than 30°. More specifically, the upper surface inclination angle θ2 is set to be 22.5°. In other words, the upper surface 222a is inclined so as to extend parallel to the lower inclined surface D11 of the disk-shaped substrate D. 1 and 5, when the disk-shaped substrate D is supported by the support part 20, the portions of the support part 20 other than the upper surface 222a are disposed at a distance from the disk-shaped substrate D. In this embodiment, the support members 200 are disposed so that the lengths of imaginary lines extending radially from the center line C1 toward the upper surface 222a of each support member 200 are the same.

[0028] The upper surface 222a includes an anti-slip portion K that prevents the disk-shaped substrate D from slipping. Specifically, the anti-slip portion K according to this embodiment has an uneven shape consisting of steps as shown in FIG. 6. The anti-slip portion K has the function of increasing the static friction coefficient between the upper surface 222a and the lower inclined surface D11. Note that the edge of the disk-shaped substrate D may be caught in the uneven shape to prevent slippage. The anti-slip portion K may be formed by subjecting the upper surface 222a to processing such as embossing or graining, or may be formed by subjecting the upper surface 222a to a so-called hairline processing, in which a large number of thin linear grooves are formed in the upper surface 222a.

[0029] 1 , the transport mechanism 40 has a function of transporting the disk-shaped substrate D supported by the support unit 20 in a predetermined direction (here, the X direction). The transport mechanism 40 according to this embodiment has a roller unit 41 and a cylinder unit 42.

[0030] The roller section 41 is disposed below the table unit 10 and supports the table unit 10 in a state in which it is possible to guide the movement of the table unit 10 in the X direction.

[0031] The cylinder portion 42 includes an air cylinder that expands and contracts in the X direction in response to the supply of air ejected from an air pump (not shown), and presses the casing 15, thereby moving the table unit 10 (casing 15) in the expansion / contraction direction.

[0032] As described above, according to the configuration of this embodiment, the circumferential portion D1 of the disk-shaped substrate D is supported from below by the upper surface 222a that constitutes the support surface of the support portion 20. Therefore, compared to using a device that grips the disk-shaped substrate D using, for example, a plurality of gripping portions that engage with the circumferential portion D1 of the disk-shaped substrate D and a gripping mechanism that moves each gripping portion toward the center O of the disk-shaped substrate D, the disk-shaped substrate D can be supported with a simpler configuration. That is, the disk-shaped substrate D can be supported without requiring a complex mechanism. Furthermore, since the disk-shaped substrate D is supported by the upper surface 222a supporting the disk-shaped substrate D's own weight, a force greater than the disk-shaped substrate D's own weight is prevented from acting on the disk-shaped substrate D. That is, excessive force is prevented from acting on the disk-shaped substrate D. Therefore, the disk-shaped substrate D can be supported with a simple configuration, and damage to the disk-shaped substrate D can be prevented.

[0033] In addition, in this embodiment, since the upper surface 222a of the support member 200 is inclined, the disk-shaped substrate D is supported with the position of the center O of the disk-shaped substrate D aligned with the center line C1 of the support portion 20, and the disk-shaped substrate D can be prevented from moving horizontally on the support portion 20.

[0034] In addition, even if the disk-shaped substrate D is chamfered and the supported surface (lower inclined surface D11) of the circumferential portion D1 that is supported by the upper surface 222a is inclined, in this embodiment, the upper surface 222a and the supported surface can be in surface contact with each other because the upper surface 222a is inclined. This allows the upper surface 222a to stably support the supported surface.

[0035] Furthermore, according to this embodiment, compared to a case where a mechanism for holding the disk-shaped substrate D is provided above the disk-shaped substrate D, the space above the disk-shaped substrate D is opened up, which makes it easier to inspect the quality of the disk-shaped substrate D by, for example, taking an image of the disk-shaped substrate D from above.

[0036] Furthermore, according to this embodiment, the disk-shaped substrate D can be stably supported even if the shape of the disk-shaped substrate D is slightly deformed. For example, consider a case where the disk-shaped substrate D is warped rather than flat, specifically, where the circumferential portion D1 of the disk-shaped substrate D has a partially wavy shape. Here, in the device that grips the disk-shaped substrate D using the multiple gripping portions and the gripping mechanism, if the gripping portions engage with the wavy portion, they cannot transmit force evenly to the circumferential portion D1, and there is a possibility that they will fail to grip the disk-shaped substrate D. In contrast, the support structure 1 according to this embodiment supports the weight of the disk-shaped substrate D from below, and can therefore stably support the disk-shaped substrate D regardless of the shape of the disk-shaped substrate D.

[0037] Furthermore, in this embodiment, the upper surface 222a includes the anti-slip portion K, which prevents the circumferential portion D1 of the disk-shaped substrate D from slipping relative to the upper surface 222a. As a result, the disk-shaped substrate D can be supported with its posture stabilized.

[0038] Furthermore, in this embodiment, the uneven shape improves the surface roughness of the non-slip portion K. This increases the static friction coefficient between the upper surface 222a and the circumferential portion D1 compared to when the non-slip portion K does not have an uneven shape, thereby further preventing the circumferential portion D1 from slipping against the upper surface 222a.

[0039] Generally, when the edge portion of the disk-shaped substrate D has an inclined surface (lower inclined surface D11) formed by chamfering or the like, the lower inclined surface inclination angle θ1, which is the exterior angle between the functional surface D12 used in device manufacturing and the lower inclined surface D11, is set in the range of 15° to 30°. In contrast, in this embodiment, the upper surface inclination angle θ2 of the upper surface 222a is set to be equal to or greater than 15° and equal to or less than 30°. Therefore, by using the lower inclined surface D11 as the supported surface and supporting it with each upper surface 222a, the contact area between the upper surface 222a and the lower inclined surface D11 can be increased. As a result, the lower inclined surface D11 can be stably supported by the upper surface 222a.

[0040] In addition, if the inclination angle θ1 of the lower inclined surface is set to be smaller than 15°, the angle is too shallow, making it difficult to sufficiently restrain the disk-shaped substrate D in the horizontal direction. In this case, the impact generated when transporting the disk-shaped substrate D makes it easy for the center O of the disk-shaped substrate D to become displaced. Furthermore, if the inclination angle θ1 of the lower inclined surface is set to be larger than 30°, the disk-shaped substrate D may become tightly stuck in the support part 20, making it difficult to remove the disk-shaped substrate D from the support part 20. In contrast, according to this embodiment, the disk-shaped substrate D can be suitably removed from the support part 20 while aligning the position of the center O of the disk-shaped substrate D with the center line C1 of the support part 20.

[0041] Furthermore, in this embodiment, the inclination angles of the upper surface 222 a of the main body 220 and the lower inclined surface D11 of the disk-shaped substrate D match, so that the contact area between the upper surface 222 a and the lower inclined surface D11 can be increased, thereby enabling the upper surface 222 a to stably support the lower inclined surface D11.

[0042] Furthermore, in this embodiment, the table body 11 and the support portion 20 are configured to be detachable. Specifically, the table body 11 and the connection portion 210 (connection base portion 211) of each support member 200 are fastened to each other by connection base fasteners 32. This configuration allows the support member 200 to be replaced depending on the size (diameter) of the disk-shaped substrate D. That is, when supporting a disk-shaped substrate D with a relatively small diameter, it is sufficient to fix a support member with a relatively short radial length to the table body 11, and when supporting a disk-shaped substrate D with a relatively large diameter, it is sufficient to fix a support member with a relatively long radial length to the table body 11. Thus, in this embodiment, the versatility of the support structure 1 is improved by making the support member 200 replaceable. Note that, as a support member with a relatively short radial length, for example, a support member with a relatively short radial distance from the platform fixing hole H located radially outward to the upper surface 222a can be used. Furthermore, as a support member having a relatively long length in the radial direction, for example, a support member having a relatively long radial distance from the base fixing hole H located on the radially outer side to the upper surface 222a can be used.

[0043] Furthermore, in this embodiment, the connection portion 210 and the main body portion 220 are configured to be detachable. Specifically, in this embodiment, the extension portion 212 of the connection portion 210 and the base portion 221 of the main body portion 220 are fastened together by base fasteners 33. This configuration allows the main body portion 220 to be replaced so that the upper surface inclination angle θ2 of the upper surface 222a can be adjusted according to the lower inclined surface inclination angle θ1 of the lower inclined surface D11. For example, assume that the type of disk-shaped substrate D transported by the support structure 1 is changed and the lower inclined surface inclination angle θ1 of the lower inclined surface D11 is changed to 30°. In this case, the worker simply removes the main body portion 220 attached to the connection portion 210 and fixes a new main body portion to the connection portion 210 that can suitably support the new type of disk-shaped substrate D. That is, the worker simply fixes a new main body portion having an upper surface with an upper surface inclination angle θ2 set to 30° or an angle close to this to the connection portion 210. This increases the contact area between the lower inclined surface D11 and the upper surface, making it possible to support the disk-shaped substrate D more stably.

[0044] Furthermore, in this embodiment, since spaces are formed between the support members 200, it is possible to use these spaces to place devices such as sensors, etc. In other words, the degree of freedom in designing the support structure 1 is improved.

[0045] Furthermore, in this embodiment, since a space is formed between each of the support members 200, even if the disk-shaped substrate D does not have a flat shape, the disk-shaped substrate D can be stably supported. For example, even if the disk-shaped substrate D partially has a bending portion having a bending shape, the disk-shaped substrate D can be stably supported by the support members 20 with the bending portion released into the space.

[0046] Furthermore, in this embodiment, since the support unit 20 has three support members 200, the disk-shaped substrate D can be supported in a more balanced manner than when the disk-shaped substrate D is supported at two points. This makes it possible to prevent the disk-shaped substrate D from falling off the support members 200 when the posture of the disk-shaped substrate D is distorted, for example.

[0047] Furthermore, in this embodiment, the circumferential portion D1 is supported by three support members 200 that are arranged at equal intervals from one another, so that the disk-shaped substrate D can be supported in a well-balanced manner.

[0048] Furthermore, in this embodiment, when the disk-shaped substrate D is supported by the support part 20, the portions of the support part 20 other than the upper surface 222a are disposed at a distance from the disk-shaped substrate D. As a result, the portions of the disk-shaped substrate D other than the circumferential portion D1 are prevented from being supported by the support part 20. Specifically, the functional surface D12 is prevented from being supported. This prevents foreign matter and the like from adhering to the functional surface D12.

[0049] The support structure 1 according to one embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment. The following modified embodiments are possible in the present invention.

[0050] (1) In the above embodiment, an example was described in which the support section 20 has three support members 200, but the number of support members 200 can be changed as appropriate.

[0051] For example, the support unit 20 may have a single support member having a mortar shape and whose diameter at the top is set to be approximately the same as the diameter of the disk-shaped substrate D. Alternatively, the support unit 20 may have a pair of support members that are opposed to each other in the radial direction and each have an approximately U-shape. In other words, the support unit 20 may have two support members.

[0052] (2) In the above embodiment, an example was described in which the upper surface 222a has a flat shape. However, the shape of the upper surface 222a is not limited to this, and the upper surface 222a may have a curved shape that bulges downward or upward.

[0053] The present invention provides a support structure for supporting a disk-shaped substrate, the support structure comprising a support portion having a support surface arranged around a center line extending in an up-down direction and inclined downward toward the center line, the support surface abutting the circumferential portion of the disk-shaped substrate from below to support the weight of the disk-shaped substrate.

[0054] According to this configuration, the circumferential portion of the disk-shaped substrate is supported from below by the support surface of the support part, so that the disk-shaped substrate can be supported without requiring a complex mechanism. Furthermore, since the support surface supports the disk-shaped substrate by supporting its own weight, the disk-shaped substrate is supported, so that a force greater than its own weight is prevented from acting on the disk-shaped substrate. In other words, excessive force is prevented from acting on the disk-shaped substrate. Therefore, it is possible to support the disk-shaped substrate with a simple configuration, and damage to the disk-shaped substrate can be prevented.

[0055] Furthermore, in this configuration, since the support surface is inclined, the disk-shaped substrate is supported with its center position aligned with the center line of the support portion, and the disk-shaped substrate can be prevented from moving horizontally on the support portion.

[0056] In addition, even if the circumferential portion of the disk-shaped substrate is chamfered and the supported surface of the circumferential portion that is supported by the supporting surface is inclined, the supporting surface and the supported surface can be in surface contact because the supporting surface is inclined, so that the supporting surface can stably support the supported surface.

[0057] In the above configuration, the support surface may include an anti-slip portion that prevents the disk-shaped substrate from slipping.

[0058] According to this configuration, the circumferential portion of the disk-shaped substrate is prevented from slipping on the support surface, so that the disk-shaped substrate can be supported in a stable position.

[0059] In the above configuration, the anti-slip portion may have an uneven shape formed on the support surface when viewed in a cross section including the center line.

[0060] According to this configuration, the uneven surface roughness of the non-slip portion is improved, which increases the static friction coefficient between the support surface and the circumferential portion compared to when the non-slip portion does not have an uneven surface, thereby further preventing the circumferential portion from slipping on the support surface.

[0061] In the above configuration, an inclination angle of the support surface with respect to a radial direction of a circle centered on the center line may be equal to or greater than 15° and equal to or less than 30°.

[0062] Generally, when the edge portion of a disk-shaped substrate has an inclined surface due to chamfering or the like, the exterior angle between the functional surface used in device manufacturing and the inclined surface is often set within a range of 15° to 30°. Therefore, according to the above configuration, by using the inclined surface as the supported surface and supporting it with the supporting surface, the contact area between the supporting surface and the supported surface can be increased. As a result, the supported surface can be stably supported by the supporting surface.

[0063] In the above configuration, the circumferential portion of the disk-shaped substrate has a supported surface that is inclined downward toward the center of the disk-shaped substrate and can be supported by the supporting surface, and the supporting surface may be inclined so as to extend parallel to the supported surface.

[0064] With this configuration, the inclination angles of the supporting surface and the supported surface are the same, which increases the contact area between the supporting surface and the supported surface, thereby enabling the supported surface to be stably supported by the supporting surface.

[0065] In the above configuration, the support portion may have a plurality of support members arranged at intervals around the center line, and each of the plurality of support members may include an upper surface that constitutes the support surface.

[0066] According to this configuration, since a space is formed between each support member, this space can be used to place devices such as sensors, thereby increasing the degree of freedom in designing the support structure for the disk-shaped substrate.

[0067] In the above configuration, the plurality of support members may include at least three support members.

[0068] This configuration allows the disk-shaped substrate to be supported in a more balanced manner than when the disk-shaped substrate is supported at two points, thereby preventing the disk-shaped substrate from falling off the support member when the disk-shaped substrate loses its position.

[0069] In the above configuration, the plurality of support members may be arranged at equal intervals around the center line.

[0070] According to this configuration, the circumferential portion is supported by a plurality of support members arranged at equal intervals from one another, so that the disk-shaped substrate can be supported in a well-balanced manner.

[0071] In the above configuration, when the disk-shaped substrate is supported by the support portion, a portion of the support portion other than the support surface may be disposed at a distance from the disk-shaped substrate.

[0072] According to this configuration, the support portion prevents portions of the disk-shaped substrate other than the circumferential portion from being supported by the support portion. Specifically, the support portion prevents the functional surface of the disk-shaped substrate used in device manufacturing from being supported. This makes it possible to suppress adhesion of foreign matter and the like to the functional surface.

Claims

1. A support structure for supporting a disk-shaped substrate comprising a support part having a support surface arranged around a center line extending in the vertical direction and inclined downward toward the center line, the support surface contacting the circumferential portion of the disk-shaped substrate from below to support the weight of the disk-shaped substrate.

2. A support structure for a disk-shaped substrate as claimed in claim 1, wherein the support surface includes an anti-slip portion for preventing the disk-shaped substrate from slipping.

3. A support structure for a disk-shaped substrate as described in claim 2, wherein the anti-slip portion has an uneven shape formed on the support surface when viewed in a cross section including the center line.

4. A support structure for a disk-shaped substrate as claimed in any one of claims 1 to 3, wherein the inclination angle of the support surface relative to the radial direction of a circle centered on the center line is 15° or more and 30° or less.

5. A support structure for a disk-shaped substrate as claimed in any one of claims 1 to 3, wherein the circumferential portion of the disk-shaped substrate has a supported surface that is inclined downwardly towards the centre of the disk-shaped substrate and capable of being supported by the supporting surface, and the supporting surface is inclined so as to extend parallel to the supported surface.

6. A support structure for a disk-shaped substrate as claimed in any one of claims 1 to 3, wherein the support portion has a plurality of support members arranged at intervals around the center line, and each of the plurality of support members includes an upper surface constituting the support surface.

7. A support structure for a disk-shaped substrate according to claim 6, wherein the plurality of support members include at least three support members.

8. A support structure for a disk-shaped substrate as set forth in claim 6, wherein the plurality of support members are disposed at equal intervals around the center line.

9. A support structure for a disk-shaped substrate as described in any one of claims 1 to 3, wherein, when the disk-shaped substrate is supported by the support portion, a portion of the support portion other than the support surface is positioned at a distance from the disk-shaped substrate.

Images