JP2008034553A - Substrate retaining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To retain a substrate after being correctly positioned, and to relieve the shock when releasing the retention. <P>SOLUTION: A spin chuck 1 is provided with three sets of positioning and retaining members F1-F3 and three sets of auxiliary retaining members S1-S3, which are respectively abutted against different positions of the circumferential rim parts of a wafer W, to retain the same in substantially horizontal posture. The positioning and retaining members F1-F3 are operated together by a first operation conversion mechanism FT1, while the auxiliary retaining members S1-S3 are operated together by the second operation conversion mechanism FT2. When the wafer W is to be retained, the wafer W is positioned and retained by the positioning and retaining members F1-F3 at first; and thereafter, the wafer W is retained auxiliarily by the auxiliary retaining members S1-S3. When the retention of the wafer W is released, the retention by the auxiliary retaining members S1-S3 is released first; and thereafter, retention by the positioning and retaining members F1-F3 is released. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate holding device that holds a substrate. Examples of substrates to be held include semiconductor wafers, liquid crystal display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, and photomask substrates. A substrate etc. can be mentioned.

  In a manufacturing process of a semiconductor device or a liquid crystal display device, a substrate processing apparatus is used for processing a substrate with a processing liquid or the like. A single-wafer type substrate processing apparatus that processes substrates one by one is provided with a spin chuck that holds and rotates the substrate. The spin chuck holds and rotates the substrate while rotating the substrate. Then, the substrate processing is performed by supplying a processing solution or the like.

  The spin chuck includes a disc-shaped spin base, a plurality of clamping members provided on the peripheral edge of the spin base, and a clamping member driving mechanism that operates the plurality of clamping members. For example, in a spin chuck applied to holding a semiconductor wafer that is a substantially circular substrate, six clamping members are provided at equal intervals on the peripheral edge of the spin base, and these six clamping members cooperate with each other. A semiconductor wafer is clamped.

  Some of the spin chucks provided in the conventional substrate processing apparatus in which a wafer having a diameter of about 20 centimeters is the mainstream, have held the wafer by three clamping members, but have a diameter of about 30 centimeters or more. In a recent substrate processing apparatus that needs to handle a large-diameter wafer, it is usual to provide six clamping members. This is because, when a large-diameter wafer is sandwiched between three clamping members, non-negligible bending occurs at the peripheral edge of the substrate, and not only the substrate holding becomes unstable, but also processing irregularities on the substrate surface may occur. .

  The clamping member has, for example, a wafer support portion that comes into contact with the peripheral portion of the lower surface of the wafer and an end surface contact portion that comes into contact with the peripheral end surface of the wafer. The end surface abutting portion has, for example, a minute roll-shaped holding groove that opens toward the wafer end surface in a side view, and is configured to receive and hold the wafer peripheral end surface in the holding groove. The wafer to be held is once placed on the wafer support portion, and then the end surface abutting portion moves so as to abut on the peripheral end surface of the wafer, and the wafer is moved in cooperation with the end surface abutting portions of other clamping members. Hold. At this time, the end surface abutting portion slightly lifts the peripheral edge of the wafer, whereby the peripheral edge of the wafer is held at a position spaced apart from the wafer supporting portion by a slight distance. When the end surface abutting portion is separated from the peripheral surface of the wafer to release the wafer, the peripheral portion of the wafer is lowered by its own weight and landed on the wafer support portion.

When holding the wafer carried by the substrate transfer robot on the spin chuck and when releasing the wafer held by the spin chuck in order to dispense the processed wafer, the six clamping members are driven simultaneously. The
Each clamping member is urged toward the holding position by a spring. Therefore, the holding member driving mechanism generates a driving force that moves the holding member to the open position against the spring force when the holding of the wafer is to be released, and an external force to the holding member when the wafer is to be held. And the clamping member is guided to the holding position by the spring force. This spring force holds the wafer.
JP 2004-111902 A

  When the substrate transfer robot carries the wafer into the spin chuck and places the wafer on the wafer support portion of the holding member, it is rare that the center of the wafer coincides with the rotation center of the spin chuck. Therefore, the wafer is normally placed on the spin chuck in an eccentric state. If the wafer in the eccentric state is clamped simultaneously by the six clamping members, the wafer is held with almost no correction for the eccentric state. This is presumed to be because the other clamping members contact the peripheral edge surface of the wafer earlier than the first clamping member that contacted the wafer peripheral edge surface corrects the wafer position, thereby obstructing correction of the wafer position. Is done. Although it is possible if the six end surface abutting portions can be adjusted so as to sandwich the wafer at a position that does not decenter, the adjustment takes time, and even if a jig or the like is used, complicated adjustment is required.

In addition, due to the limit of processing accuracy of individual parts, the limit of assembly accuracy, and variations in spring constant, it is actually necessary to bring the end surface abutting portions of the six clamping members into contact with the peripheral surface of the wafer with equal force. It is impossible. From the above, it is impossible to make the center of the wafer exactly coincide with the rotation center of the spin chuck (within the required accuracy range).
As described above, when the spin chuck is rotated in a state where the wafer is eccentric, the larger the diameter of the wafer is, the larger centrifugal force is generated, which may make the wafer holding unstable.

Further, when the wafer is released from the spin chuck, since the wafer is in an eccentric state, the substrate transfer robot receives the eccentric wafer. Therefore, there is a possibility that the wafer may fall when the substrate is delivered.
Further, when the holding of the wafer by the six clamping members is simultaneously released, the wafer held in a state of being spaced apart upward from the wafer support unit falls to the wafer support unit all at once. Due to the impact at the time of dropping, particles may be generated to contaminate the wafer, the wafer may fall from the spin chuck, or the wafer may be chipped.

Accordingly, an object of the present invention is to provide a substrate holding device that can accurately align and hold a substrate.
Another object of the present invention is to provide a substrate holding device that can alleviate an impact when releasing the holding of the substrate.
Still another object of the present invention is to provide a substrate holding apparatus capable of accurately aligning and holding a substrate with a simple configuration.

  Still another object of the present invention is to provide a substrate holding apparatus that can reduce an impact when releasing the holding of the substrate with a simple configuration.

  In order to achieve the above object, at least four of the inventions according to the first aspect of the present invention are in contact with different positions of the edge of the substrate (W) and cooperate to hold the substrate (for example, hold in a substantially horizontal position). Holding members (F1 to F3, S1 to S3) and holding member driving means (FT1, FT2, 51; FT1, FT2, M1; FT1, FT2, M1) for driving the at least four holding members when holding and releasing the substrate M2, 161, 162, 168, 178, 181, 182), and the at least four holding members are classified into a plurality of groups (F, S) each including at least one holding member, The holding member driving means drives the holding members of each group while shifting the timing from the holding members of at least one other group when holding or releasing the substrate. It is a holding device. The alphanumeric characters in parentheses indicate corresponding components in the embodiments described later. The same applies hereinafter.

  According to this configuration, when holding the substrate or releasing the holding of the substrate, the holding members of the plurality of groups are driven at different timings. If the timing is shifted when holding the substrate, the substrate position is first corrected by the group of holding members that contact the edge of the substrate, and then the remaining holding member contacts the edge of the substrate. Will come to hold. As a result, the substrate can be accurately aligned and held. In addition, if the timing is shifted when releasing the holding of the substrate, the holding of the substrate can be released in stages, so that the substrate does not fall at a stretch, and the impact at the time of releasing the holding of the substrate Can be relaxed.

  According to a second aspect of the present invention, the at least four holding members are configured to be able to contact each of different positions on the peripheral end surface of the substrate, and the plurality of groups can position and hold the substrate 3 A first group (F) made up of a plurality of positioning and holding members and a second group (S) made up of holding members other than the three positioning and holding members, wherein the holding member driving means holds the substrate. The substrate is held by the three positioning holding members (preferably only the first group positioning holding member) constituting the first group, and then the second group holding member is held by the three positioning holding members. 2. The substrate holding device according to claim 1, wherein the substrate holding device is brought into contact with a substrate held by a member.

  According to this configuration, when the substrate is held, the substrate is first sandwiched from the three directions by the three positioning holding members. Accordingly, the substrate is held in a positioned state, and thereafter, the substrate is held by the second group holding member. In this way, the edge of the substrate can be held at four or more locations with the substrate positioned accurately. In this case, since the substrate position is corrected by the three positioning holding members, the accuracy of the substrate holding position is determined by the processing accuracy and assembly accuracy of the components of the three positioning holding members. It is much easier to adjust the processing accuracy and the like of the three positioning holding members than to adjust the processing accuracy and the like between four or more (for example, six) holding members. Therefore, according to the configuration of the present invention, the substrate can be aligned and held within the required accuracy (for example, ± 0.3 mm or less).

According to a third aspect of the present invention, when the holding member driving means releases the holding of the substrate, the holding member of the second group is separated from the substrate, and thereafter, the three positioning members constituting the first group are arranged. The substrate holding apparatus according to claim 2, wherein the holding member is separated from the substrate.
According to a fourth aspect of the present invention, the at least four holding members are configured to be able to abut on different positions on the peripheral end surface of the substrate, respectively, and the plurality of groups can position and hold the substrate. A first group (F) composed of three positioning and holding members; and a second group (S) composed of a holding member other than the three positioning and holding members. When releasing the substrate held by the holding member, the second group holding member is separated from the substrate, and thereafter, the three positioning holding members constituting the first group are separated from the substrate. The substrate holding device according to claim 1.

  According to the inventions of these claims, since the holding by the positioning holding member is released (finally released) after the substrate holding by the holding member other than the positioning holding member is released, the positioning by the positioning holding member is performed. The holding of the substrate can be released in a state where the substrate is arranged at the correct position. Thereby, when a board | substrate is carried out by the hand of a board | substrate conveyance robot etc. after that, it can suppress or prevent that conveyance defects, such as a fall of a board | substrate, arise.

According to a fifth aspect of the present invention, the at least four holding members move to a holding position while lifting the substrate when abutting against the substrate, and are opened while allowing the substrate to descend by its own weight when being separated from the substrate. It is a board | substrate holding apparatus as described in any one of Claims 1-4 comprised so that it may move to.
According to this configuration, if the driving timing of the plurality of holding members is shifted when holding the substrate, the rising timing of the edge of the substrate is shifted at each portion, so that the substrate can be gradually lifted, and the substrate holding The shock at the time can be reduced. Also, if the drive timing of the plurality of holding members is shifted when the substrate is released, the lowering timing of the edge of the substrate will be shifted in each part, so that the substrate will not drop at once, and the substrate holding release The impact at the time can be reduced.

  According to a sixth aspect of the present invention, the holding member driving means includes a plurality of operating members (34, 44) respectively connected to the holding members of the individual groups, and sequential operating means for sequentially operating the plurality of operating members ( 51; M1, M2, 161, 162, 168, 178, 181, 182). The substrate holding device according to any one of claims 1 to 5. According to this configuration, the plurality of holding members can be operated with a time interval between the groups by sequentially operating the plurality of operating members.

  According to a seventh aspect of the invention, the plurality of actuating members are between a holding position corresponding to a state where the holding member holds the substrate and an open position corresponding to a state where the holding member is separated from the substrate. The sequential actuating means (51) displaces the actuating member between a holding position and an open position, and applies a driving force in common to the actuating members of the individual groups. A drive force transmitting member (52) capable of engaging, wherein engagement or disengagement of the drive force transmitting member and each of the plurality of groups of actuating members occurs at intervals. It is a board | substrate holding apparatus of description.

  According to this configuration, by driving the driving force transmission member, the operating member operates with a time interval, and accordingly, the plurality of holding members operate with a time interval between the groups. In this way, a plurality of holding members can be driven at different timings for each group using a single driving source (59) that applies a driving force to the driving force transmitting member. Accordingly, the substrate can be accurately aligned and held with a simple configuration, and the impact on the substrate when the substrate holding is released can be reduced.

According to an eighth aspect of the present invention, a stroke of the driving force transmission member from the disengaged state to the engaged state of the driving force transmitting member and the plurality of operating members is different for each operating member. The substrate holding device according to claim 7. With this configuration, the plurality of actuating members can be driven at different timings.
The invention according to claim 9 is a rotation base (21) for supporting the at least four holding members, a rotation drive mechanism (2) for rotating the rotation base, the rotation drive mechanism, and the holding member driving means. And a control means (100) for operating the holding member drive means in a state in which the rotation drive mechanism is stopped and rotation of the rotation base is stopped. The substrate holding device according to the item.

  With this configuration, the substrate can be accurately positioned and held in a state where the rotation of the spin base is stopped, and then the substrate can be rotated by rotating the spin base. By accurately positioning the substrate, the center of gravity of the substrate and the rotation center of the spin base can be matched with high accuracy, so that the centrifugal force acting on the substrate can be minimized, and the substrate during rotation Can be maintained stably. On the other hand, in a state where the rotation of the spin base is stopped, the holding of the substrate can be released while alleviating the impact caused by the falling of the substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an illustrative view for explaining the configuration of a substrate processing apparatus according to an embodiment of the present invention. This substrate processing apparatus simultaneously combines a thin film formed on the back surface of a semiconductor wafer (hereinafter simply referred to as “wafer”) W, which is a substantially circular substrate, and a thin film formed on the peripheral edge and end surface of the front surface of the wafer W. It can be removed. The substrate processing apparatus holds a wafer W substantially horizontally with its surface facing upward, and a spin cup 1 that rotates about a vertical axis passing through the substantially center of the held wafer W as a processing cup (not shown). It is prepared in.

  The spin chuck 1 is coupled to a rotation shaft that is a drive shaft of a motor 2 as a rotation drive mechanism and is rotated. The rotary shaft is a hollow shaft, and a treatment liquid supply pipe 3 capable of supplying pure water (deionized pure water) or an etching liquid is inserted into the rotation shaft. A central axis nozzle (fixed nozzle) having a discharge port is coupled to the processing liquid supply pipe 3 at a position close to the center of the lower surface of the wafer W held by the spin chuck 1. Then, pure water or an etching solution can be supplied toward the lower surface of the wafer W.

Pure water or etching liquid is supplied to the processing liquid supply pipe 3 at a required timing via the pure water supply valve 4 connected to the pure water supply source or the etching liquid supply valve 5 connected to the etching liquid supply source. It has come to be.
As the etching solution, a type corresponding to the type of thin film to be removed from the surface (upper surface or lower surface) of the wafer W is applied. For example, when removing a metal film such as a copper thin film from the lower surface of the wafer W, for example, a mixed solution of hydrochloric acid and hydrogen peroxide solution, a mixed solution of hydrofluoric acid and hydrogen peroxide solution, or hydrofluoric acid and nitric acid Is used as an etching solution. Further, when removing the polysilicon film, the amorphous silicon film or the silicon oxide film from the wafer W, for example, a mixed solution of hydrofluoric acid and nitric acid is used as an etching solution. Further, when removing the oxide film on the wafer W, for example, dilute hydrofluoric acid is used as an etching solution.

Although not shown, in order to supply pure water or an etching solution toward the upper surface of the wafer W, there is further provided a scan nozzle that can reciprocate between the position above the wafer W and a position off the wafer W. It may be provided. This scan nozzle is used when processing is performed on the entire upper surface of the wafer W.
Above the spin chuck 1, a disc-shaped blocking plate 6 that faces the wafer W held by the spin chuck 1 is provided horizontally. The blocking plate 6 is formed in a size that can cover almost the entire upper surface of the wafer W, and can be rotated around the vertical axis in the vicinity of the tip of the arm 8 coupled to the lifting drive mechanism 7. It is attached as follows.

  The blocking plate 6 can be moved up and down with respect to the spin chuck 1 by the lifting drive mechanism 7. Further, the blocking plate 6 can be rotated on the same rotation axis as the rotation axis of the spin chuck 1 by the rotation drive mechanism 9, and nitrogen gas as an inert gas is removed from the blocking plate 6. And the wafer W can be discharged into a space. Nitrogen gas is introduced from the nitrogen gas supply valve 10 through the nitrogen gas supply pipe 11 to a nitrogen gas discharge port (not shown) provided near the center of the lower surface of the blocking plate 6. In addition, pure water or other processing liquid from the pure water supply valve 12 can be supplied to the upper surface of the wafer W from a nozzle provided on the central lower surface of the blocking plate 6 as necessary.

  FIG. 2 is a plan view of the spin chuck 1. The spin chuck 1 includes a disk-shaped spin base 21 (rotation base), and a plurality of (six in this embodiment) holding members F1 are arranged on the upper surface of the spin base 21 at substantially equal angular intervals on the peripheral edge thereof. -F3, S1-S3 are arranged. Among these, the three holding members F1 to F3 arranged every other along the circumferential direction constitute a first holding member group F (first group), and these work together to form the wafer W. It operates to hold and release the holding. The remaining three holding members S1 to S3 constitute a second holding member group S (second group), which operate in conjunction with each other to hold the wafer W and release the holding.

  The holding members F1 to F3 constituting the first holding member group F hold the wafer W at end face positions at an angular interval of approximately 120 degrees. Further, the holding members S1 to S3 constituting the second holding member group S hold the wafer W at the end face positions at an angular interval of approximately 120 degrees. In the case where the wafer W is held by both the first and second holding member groups F and S, that is, all of the holding members F1 to F3 and S1 to S3, six end face positions at an angular interval of approximately 60 degrees are used. The wafer W can be clamped.

  In this embodiment, the holding members F <b> 1 to F <b> 3 constituting the first holding member group F are positioning holding members for positioning the wafer W so as to be centered with respect to the rotation axis of the spin base 21. That is, the center of the wafer W can be positioned on the rotation axis of the spin base 21 by sandwiching the wafer W by the positioning holding members F1 to F3. On the other hand, the holding members S <b> 1 to S <b> 3 constituting the second holding member group S are auxiliary holding members that auxiliaryly hold the wafer W positioned and held by the first holding member group F. The processing accuracy, assembly accuracy, and adjustment accuracy of the positioning holding members F1-F3 and the drive mechanism that drives the positioning holding members F1-F3 are higher than the processing accuracy, assembly accuracy, and adjustment accuracy of the auxiliary holding members S1-S3 and the drive mechanism. In other words, regarding the auxiliary holding members S1 to S3 and the drive mechanism thereof, the processing accuracy and assembly accuracy of the components and the adjustment accuracy thereof do not have to be very high. This is because the positioning accuracy of the wafer W is ensured by holding the wafer W by the positioning holding members F1 to F3.

3 and 4 are perspective views for explaining the arrangement of the motion conversion mechanism provided in the spin base 21. FIG. FIG. 3 shows a configuration in which the upper plate 22 (see FIG. 5) of the spin base 21 is removed, and FIG. 4 shows the upper plate 22 and the lower plate 23 (see FIG. 5) of the spin base 21. The configuration is also shown in FIG.
The spin base 21 includes a first motion conversion mechanism FT1 for operating the holding members F1, F2, and F3 in conjunction with each other, and a second motion conversion mechanism FT2 for operating the holding members S1, S2, and S3 in conjunction with each other. And are provided. The first motion conversion mechanism FT1 includes link mechanisms 31, 32, and 33 for operating the holding members F1, F2, and F3, respectively, and a first interlocking ring as an operation member for interlocking these link mechanisms 31 to 33. 34. Similarly, the second motion conversion mechanism FT2 includes link mechanisms 41, 42, and 43 for operating the holding members S1, S2, and S3, respectively, and a first operation member as an operating member for linking these link mechanisms 41 to 43. 2 interlocking rings 44.

  The first interlocking ring 34 and the second interlocking ring 44 are substantially annular members arranged concentrically with the rotation axis of the spin base 21, and the second interlocking ring 44 is outside the first interlocking ring 34. Is arranged. These first and second interlocking rings 34 and 44 can be moved up and down along the rotation axis of the spin base 21, and the holding members F <b> 1 to F <b> 3 are operated by moving the first interlocking ring 34 up and down. The holding members S1 to S3 can be operated by raising and lowering the second interlocking ring 44.

  FIG. 5 is a longitudinal sectional view of the spin chuck 1. The spin base 21 is configured by fixing an upper plate 22 and a lower plate 23 with bolts, and accommodates the first and second motion conversion mechanisms FT1 and FT2 between the upper plate 22 and the lower plate 23. A space is formed. A through hole 24 that penetrates the spin base 21 is formed in the center of the upper plate 22 and the lower plate 23. The treatment liquid supply pipe 3 is disposed so as to pass through the through hole 24 and further through the rotation shaft 25 of the spin chuck 1. A central axis nozzle 26 having a discharge port 26 a facing the center of the lower surface of the wafer W held by the spin chuck 1 is fixed to the upper end of the processing liquid supply pipe 3.

  The rotary shaft 25 is integrated with the drive shaft of the motor 2 and is provided through the motor 2. A casing 27 is disposed so as to surround the motor 2, and the casing 27 is further surrounded by a cylindrical cover member 28. The upper end of the cover member 28 extends to the vicinity of the lower surface of the spin base 21, and a seal mechanism 29 is disposed on the inner surface near the upper end. The seal mechanism 29 is in sliding contact with a seal member 30 fixed to the lower surface of the spin base 21, so that the spin base 21, the cover member 28, A mechanism housing space 50 is formed which is a sealed space that is partitioned by the outer space and is shielded from the external atmosphere.

  The mechanism housing space 50 is provided with a sequential operation mechanism 51 for sequentially operating the first and second interlocking rings 34 and 44 as operation members. The sequential operation mechanism 51 includes a driving ring 52 as a driving force transmitting member disposed below the first and second interlocking rings 34 and 44 so as to face the lower surfaces thereof, and the driving ring 52 as a rotating shaft. And a vertical drive mechanism 55 that moves up and down along 25. The drive ring 52 is a plate-like annular member disposed along a plane (horizontal plane) orthogonal to the rotation shaft 25, and the surface of the first and second interlocking rings 34, 44 side has a plate-like ring shape. A resin plate 53 is fixed. The upper surface of the resin plate 53 forms a horizontal contact surface 54 that contacts the lower surfaces of the first and second interlocking rings 34 and 35 (hereinafter referred to as the contact surface of the drive ring 52).

  By raising the drive ring 52 by the vertical drive mechanism 55, the contact surface 54 can be brought into contact with the lower surfaces of the first and second interlocking rings 34 and 44. The first and second interlocking rings 34 and 44 are moved up and down by the vertical drive mechanism 55 in a state where the contact surface 54 is in contact with the first and second interlocking rings 34 and 44. Can be moved up and down.

  In a state where the drive ring 52 is at a sufficiently lower position and the contact surface 54 is not in contact with any of the first and second interlocking rings 34 and 44 (the state shown in FIG. 5), the first and second Between the lower surfaces of the two interlocking rings 34 and 44, a height difference of only a step Δh is generated. More specifically, the lower surface of the first interlocking ring 34 corresponding to the positioning holding members F1 to F3 is higher by the step Δh than the lower surface of the second interlocking ring 44 corresponding to the auxiliary holding members S1 to S3. It is in. Therefore, when the drive ring 52 moves up, the contact surface 54 first lifts the second interlocking ring 44 and lifts the first interlocking ring 34 with a delay corresponding to the step Δh. On the other hand, when the drive ring 52 descends, the abutment surface 54 is first separated from the lower surface of the first interlocking ring 34 and then separated from the lower surface of the second interlocking ring 44 with a delay corresponding to the step Δh. . In this way, the stroke of the vertical movement of the drive ring 52 from the disengaged state (separated state) to the engaged state (contact state) of the drive ring 52 and the first and second interlocking rings 34 and 44 is as follows. The first and second interlocking rings 34 and 44 are different.

  In this embodiment, the holding members F1 to F3 corresponding to the first interlocking ring 34 arranged on the inner side are used as positioning holding members, and the holding members S1 to S3 corresponding to the second interlocking ring 44 arranged on the outer side are used. Although the auxiliary holding member is used, the holding members F1 to F3 may be used as auxiliary holding members and the holding members S1 to S3 may be used as positioning holding members. In this case, the lower surface of the second interlocking ring 44 may be arranged at a position higher than the lower surface of the first interlocking ring 34 by a step Δh.

  6 and 7 are perspective views for explaining the configuration of the sequential operation mechanism 51, and FIG. 8 is a partially cutaway view of the drive ring 52 and the resin plate 53 for explaining the configuration of the vertical drive mechanism 55. FIG. The vertical drive mechanism 55 is a base 56 fixed to the upper lid portion 27 a of the casing 27, a main body portion 57 A is fixed to the base 56, and an upper end of the shaft portion 57 B is connected as a vertical movement guide means to the drive ring 52. A linear bush 57, a rotating ring 58 rotatably held between the base 56 and the driving ring 52, and an air cylinder 59 as a rotation driving means for reciprocatingly rotating the rotating ring 58 by a predetermined angle; And a cam mechanism 60 as a motion converting means for converting the rotation of the rotary ring 58 into the vertical movement of the drive ring 52.

  The base 56 is formed in an annular shape having an insertion hole through which the rotary shaft 25 is inserted at the center. Three linear bushes 57 are arranged on the upper surface side of the base 56 at equal intervals in the circumferential direction. Each of these linear bushes 57 is configured to guide the shaft portion 57B in the vertical direction by a cylindrical main body portion 57A fixed along the vertical direction parallel to the rotation shaft 25. The upper end of each shaft portion 57B is coupled to the lower surface of the drive ring 52. As a result, the drive ring 52 can move up and down along the rotation shaft 25. A coil spring 57C is wound around the shaft portion 57B. When the drive ring 52 descends, the coil spring 57 receives this and softens the shock.

  From the inner periphery of the base 56, the fixed cylinder 61 rises upward along the rotation shaft 25. The rotating shaft 25 is inserted through the inside of the fixed cylinder 61. An outward flange 61a is formed in the vicinity of the upper edge portion of the fixed cylinder 61, and a bearing mounting portion is formed above the flange 61a. An inner ring of a ring-shaped bearing 62 is fixed to the bearing mounting portion. The outer ring of the bearing 62 is fixed to the inner peripheral part of the rotating ring 58. Thereby, the rotating ring 58 is supported so as to be rotatable around the rotating shaft 25. In the rotating ring 58, elongated holes 63 are formed at three locations at substantially equal intervals in the circumferential direction. The long hole 63 is formed to extend in the circumferential direction. The shaft portion 57 </ b> B of the linear bush 57 is inserted into the long hole 63. The length of the long hole 63 in the circumferential direction is slightly longer than the reciprocating rotation width of the rotating ring 58, so that the rotating ring 58 can reciprocate without interfering with the shaft portion 57 </ b> B of the linear bush 57. It is like that.

  The air cylinder 59 includes a cylinder body 59A fixed to the upper surface of the base 56, and a rod 59B that advances and retreats relative to the cylinder body 59A. In this embodiment, the air cylinder 59 performs control to expand and contract the rod 59B into the cylinder body 59A by an electromagnetic valve. The cylinder body 59A is attached to the base 56 so as to advance and retract the rod 59B in a direction substantially parallel to the tangent to the outer periphery of the rotary ring 58. A joint 65 is fixed to the tip of the rod 59B. The joint 65 is coupled to a shaft 67 attached to the link block 66. The link block 66 is fixed to the lower surface of the rotating ring 58. The shaft 67 is attached to the link block 66 in a posture along the vertical direction, and projects downward from the link block 66. The joint 65 couples the rod 59B to the shaft 67 in a state in which relative rotation around the vertical axis is allowed. With this configuration, when the air cylinder 59 is driven to move the rod 59B forward and backward, the linear motion of the rod 59B is transmitted to the rotary ring 58 via the joint 65 and the link block 66, and the rotation of the rotary ring 58 is rotated. Converted into movement.

  Three cam mechanisms 60 are provided at substantially equal intervals along the outer periphery of the rotating ring 58. Each cam mechanism 60 includes a cam block 70 fixed to the upper surface of the rotating ring 58 and a cam follower 71 that engages with the cam block 70. The three cam followers 71 respectively corresponding to the three cam blocks 70 are attached to the outer surface of the drive ring 52 at substantially equal intervals in the circumferential direction. In this embodiment, the cam follower 71 is composed of a roller member that can rotate around a rotation axis along the radial direction of the drive ring 52.

  The cam block 70 is generally formed in a rectangular parallelepiped shape that extends along the tangential direction of the outer periphery of the rotating ring 58. The cam block 70 is formed with a cam groove 72 that is opened inward (rotating shaft 25 side). The cam groove 72 is formed obliquely from the bottom surface of the cam block 70 toward the top surface. The bottom surface of the cam groove 72 is along the tangential direction of the rotating ring 58 and forms a cam surface 73 formed of an inclined surface having a constant gradient.

  The cam follower 71 is located in a space defined by the cam groove 72 of the cam block 70 and the upper surface of the rotating ring 58. When drive air is not supplied to the air cylinder 59, the rod 59B is in the maximum extended state. At this time, the cam follower 71 is at the lowest part in the cam groove 72 and is in contact with the upper surface of the rotating ring 58. This state is shown in FIG.

  From this state, when driving air is supplied to the air cylinder 59, the rod 59B expands and contracts to the cylinder body 59A. Thereby, when the rotating ring 58 rotates, the cam block 70 and the cam follower 71 are relatively displaced. As a result, the cam follower 71 rolls along the cam surface 73 to displace upward from the upper surface of the rotating ring 58 and reach the state shown in FIG. As a result, the drive ring 52 fixed to the cam follower 71 is displaced upward. That is, the cam surface 73 is formed in an inclined surface that becomes higher toward the upstream side in the rotational direction of the rotating ring 58 caused by the air cylinder 59 being driven and the rod 59B contracting.

  When the supply of driving air to the air cylinder 59 is stopped, the rod 59B returns to the extended state. As a result, the cam follower 71 rolls and descends on the cam surface 73 and returns to the state of contacting the upper surface of the rotating ring 58 (see FIG. 6). Along with this, the drive ring 52 also descends. The coil spring 57C wound around the shaft portion 57B of the linear bush 57 receives the drive ring 52 that descends to the initial position when the supply of drive air to the air cylinder 59 is stopped, and absorbs the impact.

  FIG. 9 is a perspective view for explaining the configuration of the link mechanism 31 constituting the first motion conversion mechanism FT1. The holding member F1 is fixed to the upper end of the shaft 35 that can rotate in the vertical direction, and faces the end surface of the wafer W at a position away from the rotational axis of the shaft 35 in a substantially wedge-shaped plate-like portion 95 in plan view. In this way, the contact portion 96 is erected. A wafer support portion 95 a is projected from the rotation center of the plate-like portion 95. The wafer support portion 95a is provided at a position corresponding to a position that enters inward from the peripheral portion by a minute distance on the lower surface of the wafer W, and supports the peripheral portion of the lower surface of the wafer W from below.

  A lever 36 that protrudes laterally below the holding member F <b> 1 is fixed to the shaft 35, and a pin 36 a that extends vertically upward is provided at the tip of the lever 36. The link mechanism 31 includes a lever 36, a swing plate 37 having an elongated hole 37 a that engages with the lever 36, a crank member 38 coupled to the swing plate 37, and a shaft portion 38 a of the crank member 38. A lever 39 having a bearing portion 39a that is rotatably supported, a crank member 40 coupled to the lever 39, a bearing member 45 that rotatably supports one shaft portion 40a of the crank member 40, and a crank member And a lifting member 46 having a long hole 46a that engages with the other shaft portion 40b. The lower end of the elevating member 46 is coupled to the upper surface of the first interlocking ring 34.

As shown in FIGS. 4 and 5, a plurality of (three in this embodiment) guide shafts 47 are equidistantly spaced vertically along the rotation shaft 25 on the upper surface side of the first interlocking ring 34. It is erected. The guide shaft 47 passes through the lower plate 23 of the spin base 21 and is held by a bush 48 provided in the spin base 21 so as to be movable up and down.
Therefore, when the first interlocking ring 34 is lifted from below by the drive ring 52, the first interlocking ring 34 moves up and down along the rotation shaft 25 while maintaining the horizontal posture. Accordingly, when the elevating member 46 moves up and down, the crank member 40 rotates around the shaft portion 40 a supported by the bearing member 45. The elongated hole 46 a formed in the elevating member 46 extends in the horizontal direction, and thereby the elevating motion of the elevating member 46 is smoothly converted into the rotation of the crank member 40.

  As the crank member 40 rotates, the lever 39 swings, and the crank member 38 supported by the bearing portion 39a moves along the circumferential direction of the spin base 21 in plan view. The long hole 37a formed in the rocking plate 37 is formed long along the radial direction of the spin base 21, and the pin 36a is engaged with the long hole 37a along the vertical direction. The plate 37 swings while moving up and down slightly with respect to the spin base 21 while maintaining a horizontal posture. As the swing plate 37 swings, the pin 36 a is displaced along the circumferential direction of the spin base 21, thereby causing the lever 36 to rotate the holding member F <b> 1 via the shaft 35. In this way, the link mechanism 31 converts the lifting / lowering movement of the first interlocking ring 34 into the turning movement of the holding member F1.

The structures of the link mechanisms 32 and 33 are the same as the structure of the link mechanism 31, and these operate in conjunction with each other by the function of the first interlocking ring 34.
Since the structures of the link mechanisms 41, 42, and 43 corresponding to the holding members S1, S2, and S3 are substantially the same as those of the link mechanism 31, the same reference numerals as those in the case of the link mechanism 31 are attached to the main parts thereof. The description is omitted. However, since the second interlocking ring 44 is located on the radially outer side of the spin base 21 with respect to the first interlocking ring 34, the shaft portion 40a of the crank member 40 is shorter than that of the link mechanism 31. Accordingly, the configuration of the bearing member 45 is slightly different. 3 to 5, reference numeral 49 denotes a guide shaft erected on the second interlocking ring 44, which has the same function as the guide shaft 47 erected on the first interlocking ring 34, and Similarly to the guide shaft 47, it is coupled to the spin base 21 via the bush 92 so as to be movable up and down.

  As shown in FIGS. 4 and 5, the elevating member 46 of the link mechanism 31, 32, 33 has a compression coil spring between the lower surface of the lower plate 23 of the spin base 21 and the upper surface of the first interlocking ring 34. 93 is wound. As a result, the first interlocking ring 34 is urged downward, and as a result, the holding member F1 is urged in the closing direction in which the abutting portion 96 faces inward in the radial direction of the spin base 21. ing.

  Further, similarly for the link mechanisms 41, 42, 43, a compression coil spring 94 is wound around the elevating member 46 between the lower surface of the lower plate 23 of the spin base 21 and the upper surface of the second interlocking ring 44. Yes. Therefore, the holding members F1, F2, F3, S1, S2, and S3 are urged toward the closing direction in which the contact portion 96 is directed inward in the radial direction of the spin base 21. Therefore, if the drive ring 52 is sufficiently below, the wafer W is held by the holding members F1 to F3 and S1 to S3 biased in the closing direction by the spring force of the compression coil springs 93 and 94. As described above, since the wafer W is elastically held by using the elastic force of the compression coil springs 93 and 94, there is an advantage that the wafer W is hardly damaged.

FIG. 10 is a side view for explaining the configuration of the holding member F1. However, the other holding members F2, F3, S1 to S3 have a common configuration.
As described above, the holding member F1 includes the wafer support portion 95a that supports the lower surface of the peripheral portion of the wafer W and the contact portion 96 that holds the peripheral end surface of the wafer W from the side. It is rotated around a vertical axis about 95a. By this rotation, the abutting portion 96 can be brought close to / separated from the peripheral end surface of the wafer W, a holding position for holding the wafer W, and an open position for releasing such holding and separating from the wafer W. And can be displaced. The contact portion 96 includes a groove-shaped wafer receiving portion 97 having an inward V-shaped cross section facing the peripheral end surface of the wafer W. When the contact portion 96 is pressed against the peripheral end surface of the wafer W and moved to the holding position, in the process, the wafer W rises to the wafer receiving portion 97 and floats upward by a minute distance from the wafer support portion 95a. It becomes a state. On the contrary, when the contact part 96 is moved from the holding position to the open position, the wafer W is lowered according to the inclination of the wafer W receiving part 97 by its own weight and placed on the wafer support part 95a.

  FIG. 11 is a block diagram for explaining a configuration related to control of the substrate processing apparatus. The substrate processing apparatus is provided with a control device 100 for controlling each part. The control device 100 includes a motor 2 for rotating the spin chuck 1, a pure water supply valve 4, an etching solution supply valve 5, a lift drive mechanism 7, a rotation drive mechanism 9, a nitrogen gas supply valve 10, and a pure water supply valve 12. The operation of the air cylinder 59 and the like is controlled.

The operation at the time of delivery of the wafer W is as follows.
When the processing is not performed on the wafer W, the control device 100 controls the lifting drive mechanism 7 to retract the blocking plate 6 to the upper retracted position, and also controls the rotation driving mechanism 9 to block it. The plate 6 is controlled to stop rotating. Further, the control device 100 controls all of the pure water supply valves 4 and 12, the etching solution supply valve 5, and the nitrogen gas supply valve 10 to be closed. Further, the control device 100 stops the motor 2 and controls the spin chuck 1 to be in a rotation stopped state.

  When an unprocessed wafer W is loaded into the spin chuck 1 by a substrate transfer robot (not shown), the control device 100 drives the air cylinder 59 prior to this. That is, driving air is supplied to the air cylinder 59. As a result, the rod 59B contracts and causes the rotation of the rotation ring 58. As a result, the drive ring 52 is raised by the action of the cam mechanism 60. The contact surface 54 of the drive ring 52 first contacts the second interlocking ring 44 and contacts the first interlocking ring 34 after a time corresponding to the step Δh. Then, when the first and second interlocking rings 34 and 44 are pushed up against the spring force of the compression coil springs 93 and 94, the holding members F1 to F3 and S1 to S3 are all in the holding position. Displace from (initial position) to open position. The position (upper position) of the drive ring 52 at this time is the “open position” of the drive ring 52.

In this state, the substrate transfer robot places the wafer W on the spin chuck 1 and then withdraws from the spin chuck 1. At this time, the wafer W is supported at six positions on the lower surface of the peripheral edge by the wafer support portions 95a of the six holding members F1 to F3 and S1 to S3.
Next, the control device 100 stops supplying drive air to the air cylinder 59. Then, the drive ring 52 is pushed downward by the first and second interlocking rings 34 and 44 urged downward by the spring force of the compression coil springs 93 and 94 and further lowered by its own weight. In this process, first, the first interlock ring 34 is separated from the contact surface 54 of the drive ring 52 and released from the support by the drive ring 52. Accordingly, the three positioning holding members F1 to F3 constituting the first holding member group F are brought into contact with the peripheral end surface of the wafer W by the action of the compression coil spring 93 and sandwich the wafer W. As a result, the wafer W is positioned so that the center of the wafer W coincides with the rotation axis of the spin base 21. Thereafter, the second interlocking ring 44 is separated from the contact surface 54 of the drive ring 52 and released from the support by the drive ring 52 with a delay corresponding to the time corresponding to the step Δh. As a result, the auxiliary holding members S <b> 1 to S <b> 3 constituting the second holding member group S come into contact with the peripheral end surface of the wafer W by the action of the compression coil spring 94 and sandwich the wafer W. The position (downward position) of the drive ring 52 at this time is the “holding position” of the drive ring 52.

  In this way, after the wafer W is positioned from the three directions by the holding by the first holding member group F, the wafer W is auxiliaryly held by the second holding member group S. As a result, the wafer W can be stably held at the six positions on the peripheral edge thereof in a state where the wafer W is positioned. The peripheral portion of the held wafer W is held by the wafer receiving portion 97 at a position spaced apart from the wafer support portion 95a by a minute distance in the holding members F1 to F3 and S1 to S3. .

  When the processing on the wafer W is completed and the processed wafer W is unloaded from the spin chuck 1, the control device 100 supplies driving air to the air cylinder 59 and contracts the rod 59B. As a result, the drive ring 52 rises, and its abutment surface 54 first abuts on the second interlocking ring 44, pushes up the second interlocking ring 44 by the step Δh, and then abuts on the first interlocking ring 34. . Thereby, the holding of the wafer W by the auxiliary holding members S1 to S2 constituting the second holding member group S is released, and thereafter, the holding by the positioning holding members F1 to F3 constituting the first holding member group F is released. It will be.

  By finally releasing the clamping by the positioning holding members F1 to F3, the wafer W can be accurately positioned with respect to the spin chuck 1 even after the clamping is released. As a result, when the wafer W is subsequently unloaded by the substrate transfer robot, the substrate transfer robot can hold the wafer W at an appropriate position, so that transfer defects can be suppressed or prevented.

  In addition, by first releasing the holding by the auxiliary holding members S1 to S3, in these auxiliary holding members S1 to S3, the peripheral edge portion of the wafer W is lowered according to the inclination of the wafer receiving portion 97 and is moved to the wafer support portion 95a. It reaches a supported state. Thereafter, the holding by the positioning and holding members F1 to F3 is released, and in these positioning and holding members F1 to F3, the peripheral portion of the wafer W descends according to the inclination of the wafer receiving portion 97 and is supported by the wafer support portion 95a. It reaches the state that was done. As a result, the wafer W does not fall on the wafer support portions 95a of the six holding members F1 to F3 and S1 to S3 at a stretch, and the wafer W can be gently landed on the wafer support portions 95a. . Thereby, generation | occurrence | production of the particle accompanying the fall of the wafer W, the defect | deletion of the wafer W, the fall of the wafer W from the spin chuck 1, etc. can be suppressed or prevented.

An example of processing contents of the wafer W from when the wafer W is loaded to when it is unloaded will be outlined below.
When the wafer W is loaded into the spin chuck 1, the control device 100 energizes the motor 2 to rotate the spin chuck 1 and controls the lift drive mechanism 7 to lower the blocking plate 6 to lower the wafer W. After being guided to a nearby height, the rotational drive mechanism 9 is energized to rotate the blocking plate 6 synchronously with the spin chuck 1.

  Thereafter, the control device 100 opens the etching solution supply valve 5 and the nitrogen gas supply valve 10. As a result, the etching solution is supplied from the central axis nozzle 26 toward the center of the lower surface of the wafer W. This etching solution is guided to the radially outward side along the lower surface of the wafer W, and goes around to the upper surface side along the end surface of the wafer W. This amount of wraparound is regulated by nitrogen gas blown from the center of the blocking plate 6. As a result, the entire back surface of the wafer W can be etched, unnecessary materials on the end surface of the wafer W can be removed by etching, and unnecessary materials on the periphery of the upper surface of the wafer W can be removed by etching.

After processing the wafer W with the etchant, the control device 100 closes the etchant supply valve 5 and opens the pure water supply valves 4 and 12. Thereby, pure water is supplied to the upper and lower surfaces of the wafer W, and pure water rinsing processing is performed.
Thereafter, the control device 100 closes the pure water supply valves 4 and 12 and controls the motor 2 to rotate the spin chuck 1 at high speed. Thereby, the moisture on the upper and lower surfaces of the wafer W is shaken off, and the drying process is performed.

After the drying process, the control device 100 stops the rotation of the spin chuck 1 and the blocking plate 6 and further retracts the blocking plate 6 to the upper retracted position. In this state, the processed wafer W on the spin chuck 1 is unloaded by the substrate transfer robot. If there is an unprocessed wafer W to be further processed, the same processing is repeated.
As described above, according to this embodiment, after the wafer W is positioned and sandwiched by the first holding member group F including the three positioning holding members F1 to F3, another three auxiliary holding members S1 to S1 are positioned. The wafer W is supplementarily clamped by the second holding member group S made of S3. It is relatively easy to match the component processing accuracy and assembly accuracy of the three positioning holding members F1 to F3, and the wafer W is positioned with respect to the rotation axis of the spin chuck 1 with an accuracy within ± 0.3 mm, for example. can do. By performing the positioning by the three positioning holding members F1 to F3 first, the position of the wafer W can be accurately maintained even when the wafer W is subsequently held by the auxiliary holding members S1 to S3. it can. In addition, the auxiliary holding members S1 to S3 do not require high parts processing accuracy and assembly accuracy.

Thus, since the wafer W can be accurately aligned and held with respect to the rotation axis of the spin chuck 1, the centrifugal force generated on the wafer W when the spin chuck 1 is rotated can be reduced. . Thereby, the wafer W can be stably held.
Furthermore, according to this embodiment, after the holding of the wafer W by the three auxiliary holding members S1 to S3 is released, the holding by the three positioning holding members F1 to F3 is released. As a result, the wafer W after being released from the nipping state is placed on the spin chuck 1 in an accurately positioned state. Therefore, it is possible to satisfactorily carry out the wafer W by the substrate transfer robot.

  In addition, since the holding of the wafer W is released in stages, the wafers W held at a minute distance above the wafer support portions 95a of the holding members F1 to F3 and S1 to S3 are all at once. Never fall. Thereby, generation | occurrence | production of the particle resulting from an impact, the defect | deletion of the wafer W, and the fall of the wafer W from the spin chuck 1 can be suppressed or prevented.

Furthermore, in this embodiment, the first holding member group F and the second holding member group S can be driven at different timings using a single drive source (air cylinder 59). Thereby, it is possible to satisfactorily hold / release the wafer W with a simple configuration.
FIG. 12 is a cross-sectional view for explaining the configuration of the substrate processing apparatus according to the second embodiment of the present invention. A configuration example of the spin chuck 1 that can be used instead of the configuration shown in FIG. 5 is shown. It is shown. In FIG. 12, parts corresponding to those shown in FIG. 5 are given the same reference numerals as those in FIG.

  In this embodiment, a substantially annular gear case 151 surrounding the rotating shaft 25 is attached to the upper cover portion 27 a of the casing 27 in the mechanism portion accommodating space 50. On the gear case 151, as shown in the plan view of FIG. 13, the first motor M <b> 1 and the second motor M <b> 2 are fixed at positions symmetrical to the rotation shaft 25. 12 is a cross-sectional view taken along line XII-XII in FIG.

  As shown in FIG. 12, bearings 152 and 153 are press-fitted inside the gear case 151 on the inner and outer peripheral sides of the inner wall surface thereof. The bearings 152 and 153 are arranged coaxially with the rotating shaft 25. A ring-shaped first gear 154 surrounding the rotation shaft 25 is fixed to the rotation-side ring of the inner bearing 152, and a ring-shaped first gear 154 surrounding the rotation shaft 25 is fixed to the rotation-side ring of the outer bearing 153. Two gears 155 are fixed. Therefore, in the gear case 151, the first gear 154 and the second gear 155 can rotate coaxially with respect to the rotation shaft 25, and the second gear 155 is located outside the first gear 154. The first gear 154 has gear teeth on the outer peripheral side, and the second gear 155 has gear teeth on the inner peripheral side.

  The pinion 156 fixed to the drive shaft of the first motor M1 enters between the first gear 154 and the second gear 155, and meshes with the first gear 154 disposed inside. Similarly, as shown in FIG. 13, the pinion 157 fixed to the drive shaft of the second motor M2 is positioned between the first gear 154 and the second gear 155, and the second pinion 157 disposed outside. It meshes with the gear 155.

  On the gear case 151, a pair of first ball screw mechanisms 161, 161 are further disposed at positions where the motors M 1, M 2 are avoided at positions facing the rotation shaft 25 (that is, the sides of the rotation shaft 25). ing. Further, on the gear case 151, the other pair of second ball screw mechanisms 162 and 162 are opposed to each other with the rotation shaft 25 interposed therebetween at positions avoiding the motors M 1 and M 2 and the first ball screw mechanisms 161 and 161. Is disposed at the position (that is, to the side of the rotation shaft 25).

  As shown in FIG. 12, the first ball screw mechanisms 161 and 161 include a screw shaft 163 arranged in parallel with the rotation shaft 25 and a ball nut 164 screwed into the screw shaft 163. . The screw shaft 163 is attached to the upper lid portion of the gear case 151 via a bearing portion 165, and the lower end thereof extends into the gear case 151. A gear 166 is fixed to the lower end of the screw shaft 163. The gear 166 enters between the first gear 154 and the second gear 155 and meshes with the first gear 154 disposed on the inner side. .

  On the other hand, a first non-rotating side movable member 168 is attached to the ball nut 164. The first non-rotating side movable member 168 is an annular member that surrounds the rotating shaft 25, and the non-rotating side ring 171 f of the first bearing 171 provided on the inner peripheral surface so as to surround the rotating shaft 25. Is fixed. The rotation-side ring 171r of the first bearing 171 is disposed on the inner side with respect to the rotation shaft 25 than the non-rotation-side ring 171f. The rotation-side ring 171r is fixed to the outer peripheral surface side of the annular first rotation-side movable member 181 that surrounds the rotation shaft 25. The first rotation-side movable member 181 is engaged with a guide rail 191 provided so as to protrude from the outer peripheral surface of the rotation shaft 25. The guide rail 191 is formed along a direction parallel to the rotation shaft 25, whereby the first rotation-side movable member 181 is guided in the direction along the rotation shaft 25 and is movable in a movable state. Coupled to the shaft 25.

  When the first motor M1 is driven to rotate the pinion 156, this rotation is transmitted to the first gear 154. As a result, the gear 166 meshing with the first gear 154 rotates, and the screw shaft 163 of the ball screw mechanisms 161 and 161 rotates. As a result, the ball nut 164 and the first non-rotating side movable member 168 coupled thereto are moved up and down along the rotation shaft 25. Since the first rotation-side movable member 181 that rotates together with the rotation shaft 25 is coupled to the first non-rotation-side movable member 168 via the bearing 171, the first non-rotation-side movable member 168 is moved up and down. Then, it is moved up and down along the guide rail 191.

  As shown in FIG. 14, another ring-shaped second non-rotating side movable member 178 is disposed outside the ring-shaped first non-rotating side movable member 168 that is moved up and down by the first ball screw mechanisms 161 and 161. Has been placed. The first non-rotating side movable member 168 is formed with a pair of projecting portions 169 and 169 projecting radially outward at positions corresponding to the ball nuts 164 of the pair of first ball screw mechanisms 161 and 161. Furthermore, another pair of protrusions 170, 170 are formed at positions shifted from the protrusions 169, 169 along the circumferential direction. Guide shafts 167 and 167 extending in a direction along the rotation shaft 25 are coupled to the pair of projecting portions 170 and 170. The guide shafts 167 and 167 are guided along the vertical direction along the rotation shaft 25, so that the first non-rotation side movable member 168 is moved to the rotation shaft 25 while maintaining a horizontal posture. Will move up and down.

  On the other hand, the ring-shaped second non-rotating side movable member 178 has a pair of projecting portions 179 and 179 projecting inward in the radial direction at positions corresponding to the second ball screw mechanisms 162 and 162. The second ball screw mechanisms 162 and 162 have the same configuration as the first ball screw mechanism 161, but the gear provided at the lower end of the screw shaft is the same as the first gear 154 in the gear case 151. The second gear 155 meshes with the second gear 155 from the inside. Accordingly, when the pinion 157 that is also meshed with the second gear 155 is driven by the second motor M2, the ball nuts of the second ball screw mechanisms 162 and 162 are raised and lowered. This ball nut is coupled to the projecting portions 179 and 179 of the second non-rotating side movable member 178.

  In the second non-rotating side movable member 178, another pair of protrusions 180, 180 are provided in a state protruding inward in the radial direction at positions shifted in the circumferential direction with respect to the protrusions 179, 179. Yes. Guide shafts 177 and 177 are coupled to the protrusions 180 and 180, respectively. These guide shafts 177 and 177 are guided along a vertical direction along the rotation shaft 25. As a result, the second non-rotating side movable member 178 moves up and down in the vertical direction along the rotation shaft 25 while maintaining a horizontal posture.

  As shown in FIG. 12, the non-rotating side ring 172 f of the second bearing 172 provided so as to surround the rotating shaft 25 is fixed to the outer peripheral surface of the second non-rotating side movable member 178. The rotation-side ring 172 r of the second bearing 172 is fixed to the inner peripheral surface of a ring-shaped second rotation-side movable member 182 that surrounds the rotation shaft 25. On the upper surface of the second rotation side movable member 182, a guide pin 192 is planted vertically upward along the rotation shaft 25.

When the second non-rotating side movable member 178 moves up and down together with the nuts of the second ball screw mechanisms 162 and 162, the second rotating side movable member 182 coupled through the second bearing 172 also moves up and down at the same time.
FIG. 15 is a perspective view for explaining the configuration of the link mechanism 31 constituting the first motion conversion mechanism FT1. Although the configuration is substantially the same as in the case of the first embodiment described above, the first interlocking ring 34 is arranged at a position where it engages with the shoulder portion 181a on the outer peripheral side of the first rotation side movable member 181. Different. Therefore, the first interlocking ring 34 moves up and down along the rotation shaft 25 together with the first rotation side movable member 181.

  FIG. 16 is an exploded perspective view showing a configuration in the vicinity of a coupling portion between the second interlocking ring 44 and the elevating member 46 of the link mechanisms 41, 42, 43. Three elevating members 46 are erected on the upper surface of the second interlocking ring 44 at intervals of 120 degrees. Further, two stepped through holes 194 are formed at intervals of 180 degrees on the upper surface of the second interlocking ring 44 at a position deviated from the elevating member 46 so that the bush 193 is fitted into the through hole 194. It has become. A guide pin 192 erected on the upper surface of the second rotation side movable member 182 is inserted into the bush 193. The guide pin 192 is fixed to the second rotary movable member 182 by screwing a screw portion 192a at the lower end thereof into a screw hole 182a formed on the upper surface of the second rotary movable member 182.

Thus, when the guide pin 192 engages with the bush 193, the second rotation side movable member 182, the second interlocking ring 44, and the lifting member 46 (however, corresponding to the link mechanisms 41, 42, 43). Relative rotation with is regulated.
Therefore, when the second non-rotating side movable member 178 is moved up and down by the second ball screw mechanism 162, the lifting member 46, the second interlocking ring 44, and the second rotating side movable member 182 are along the direction of the rotating shaft 25. Will move up and down.

  In order to detect the holding state of the wafer W by the holding members F1 to F3 and S1 to S3, as shown in FIGS. 13, 15, and 16, the height (rotation) of the first interlocking ring 34 and the second interlocking ring 44 is achieved. Position sensors 197 and 198 for detecting positions in the direction along the axis 25 are provided. The position sensors 197 and 198 are arranged in the mechanism housing space 50 (see FIG. 12), and are respectively fixed to the upper surface of the gear case 151 as shown in the partially enlarged sectional view of FIG.

  The position sensors 197 and 198 output detection signals that continuously vary according to the distance from the predetermined reference position to the first and second interlocking rings 34 and 44. As shown in FIGS. 15 and 16, for example, the position sensors 197 and 198 are constituted by reflection-type laser displacement sensors, and the laser beams L1 and L2 are sent to the predetermined lower surfaces of the first and second interlocking rings 34 and 44, respectively. A light projecting portion La that emits light toward the position, and a light receiving portion Lb that receives the reflected lights L1 ′ and L2 ′ from the first and second interlocking rings 34 and 44, respectively. According to the state, the distances from the reference position to the first and second interlocking rings 34 and 44 are detected. In order to secure the optical paths of the laser beams L1 and L2 and the reflected lights L1 ′ and L2 ′, a concave portion is formed at a corresponding position on the outer peripheral edge of the first non-rotating side movable member 168 and the inner peripheral edge of the second non-rotating side movable member 178. 168a and 178a (see FIG. 14) are respectively formed.

The light receiving unit Lb is composed of, for example, a line sensor such as a CCD element, and each detection pixel constituting the line sensor receives reflected light from a direction that forms a predetermined angle θ with respect to the optical path of the laser light L1. To do. Accordingly, the distance can be detected depending on which detection pixel receives the reflected light.
Since the position sensors 197 and 198 output detection signals that continuously fluctuate according to the heights of the first and second interlocking rings 34 and 44, the first and second interlocking rings 34 and 44 are used as holding members. A first height (open position) corresponding to a state where the contact portions 96 of F1 to F3 and S1 to S3 are retracted from the end surface of the wafer W (open state), and the holding members F1 to F3 and S1 to S3 are the wafer. A second height (holding position) corresponding to a state where the wafer W is held in contact with the end face of W (holding state), and the wafer W does not exist on the spin base 21, and the holding members F1 to F1 Each detection when the contact portion 96 of F3, S1 to S3 is at a third height corresponding to a state (no wafer state) where the contact portion 96 enters the radially inner side of the spin base 21 from the end face position of the wafer W. The signal is examined in advance during the adjustment stage and By teaching the control device 100 (see FIG. 18) of the processing apparatus, the states of the holding members F1 to F3 and S1 to S3 are detected through the detection of the heights of the first and second interlocking rings 34 and 44, respectively. can do. In this embodiment, the first height is the highest, the second height is the next highest, and the third height is the lowest.

In this embodiment, the first and second interlocking rings 34 and 44 can be moved up and down independently. Therefore, the first and second interlocking rings 34 and 44 need not have different heights on the lower surfaces in a state where they are not supported by the first and second rotation-side movable members 181 and 182 from below.
FIG. 18 is a block diagram for explaining the electrical configuration of the substrate processing apparatus. A control device 100 including a microcomputer or the like controls the first and second motors M1 and M2, and further controls a motor 2 for rotating the spin chuck 1, a rotation drive mechanism 9, and a lift drive mechanism 7. . Further, the control device 100 controls the opening and closing of the nitrogen gas supply valve 10, the pure water supply valve 12, the pure water supply valve 4 and the etching solution supply valve 5.

  The control device 100 includes a first digitizing process that digitizes detection signals output from the position sensors 197 and 198 and generates position information that is numerical information representing the positions of the first and second interlocking rings 34 and 44, respectively. Position information from the unit 101 and the second numerical processing unit 102 is input. Further, the storage unit 100M provided in the control device 100 detects a threshold value for detecting the open state of the holding members F1 to F3 and S1 to S3 and the holding state of the holding members F1 to F3 and S1 to S3. And threshold values for detecting the absence of wafers in the holding members F1 to F3 and S1 to S3 are stored in advance.

The control device 100 takes in the position information output from the first and second numerical processing units 101 and 102, and based on the position information and the threshold value, the holding members F1 to F3 and the holding members S1 to S3. The holding member state determination process for determining each state (open state, sandwiched state, no-wafer state) is executed.
When the wafer W is delivered to the spin chuck 1 by a substrate transfer robot (not shown), the control device 100 controls the motors M1 and M2 to the stop state, controls the rotation drive mechanism 9 to the stop state, and further moves the lift drive mechanism 7 to the stop state. Is controlled so that the blocking plate 6 is retracted to the retracted position above the spin chuck 1. Further, the control device 100 controls all the valves 10, 12, 4, and 5 to be closed.

  In addition, the control device 100 refers to the position information output from the first and second digitization processing units 101 and 102, and the first and second interlocking rings 34 and 44 are both in the raised position (the first height The first and second motors M1, M2 are controlled so as to be in the open state. As a result, the holding members F1 to F3 and S1 to S3 are all in an open state in which the contact portion 96 is retracted to the radially outer side of the spin base 21. In this state, the substrate transfer robot places the wafer W on the wafer support portion 95a of the plate-like portion 95 of the holding members F1 to F3 and S1 to S3.

  From this state, the control device 100 drives the first ball screw mechanism 161 and lowers the ball nut 164 by controlling the first motor M1. Thereby, since the 1st rotation side movable member 181 falls, the 1st interlocking ring 34 descends, and the raising / lowering member 46 receives the spring force and gravity from the compression coil spring 93, and descends. As a result, the positioning and holding members F1 to F3 rotate, the contact portions 96 abut against the end surface of the wafer W, and the wafer W is held by the positioning and holding members F1 to F3. Thereby, the positioning of the wafer W is achieved so that the center of the wafer W coincides with the rotation axis of the spin chuck 1.

  Next, the control device 100 controls the second motor M2 to drive the second ball screw mechanism 162 and lower the ball nut. Thereby, since the 2nd rotation side movable member 182 falls, the 2nd interlocking ring 44 falls, and the raising / lowering member 46 couple | bonded with this receives the spring force and gravity from the compression coil spring 94, and falls. As a result, the auxiliary holding members S <b> 1 to S <b> 3 are rotated by the action of the second motion conversion mechanism FT <b> 2, and the abutting portions 96 abut against the end surface of the wafer W. Thus, the wafer W is held at the six peripheral end surfaces by the six holding members F1 to F3 and S1 to S3. In each of the holding members F1 to F3 and S1 to S3, the peripheral edge of the wafer W enters the laterally V-shaped wafer receiving portion 97, so that the lower surface of the peripheral edge of the wafer W is a minute distance above the wafer support portion 95a. It is held at a separated height.

Thereafter, the control device 100 energizes the motor 2 to rotate the spin chuck 1 and controls the elevating drive mechanism 7 to lower the blocking plate 6 to guide it to a height in the vicinity of the wafer W, and then rotationally drive it. The mechanism 9 is energized and the blocking plate 6 is rotated synchronously with the spin chuck 1.
Thereafter, the control device 100 opens the etching solution supply valve 5 and the nitrogen gas supply valve 10. As a result, the etching solution is supplied from the central axis nozzle 26 toward the center of the lower surface of the wafer W. This etching solution is guided to the radially outward side along the lower surface of the wafer W, and goes around to the upper surface side along the end surface of the wafer W. This amount of wraparound is regulated by nitrogen gas blown from the center of the blocking plate 6. As a result, the entire back surface of the wafer W can be etched, unnecessary materials on the end surface of the wafer W can be removed by etching, and unnecessary materials on the periphery of the upper surface of the wafer W can be removed by etching.

After processing the wafer W with the etchant, the control device 100 closes the etchant supply valve 5 and opens the pure water supply valves 4 and 12. Thereby, pure water is supplied to the upper and lower surfaces of the wafer W, and pure water rinsing processing is performed.
Thereafter, the control device 100 closes the pure water supply valves 4 and 12 and controls the motor 2 to rotate the spin chuck 1 at high speed. Thereby, the moisture on the upper and lower surfaces of the wafer W is shaken off, and the drying process is performed.

After the drying process, the control device 100 stops the rotation of the spin chuck 1 and the blocking plate 6 and further retracts the blocking plate 6 to the upper retracted position.
Furthermore, the control device 100 drives the second motor M <b> 2 to raise the second non-rotating side movable member 178 against the spring force of the compression coil spring 94. Accordingly, the second rotation side movable member 182 is pushed up, and accordingly, the auxiliary holding members S1 to S3 are rotated by the action of the second motion conversion mechanism FT2. As a result, the contact portions 96 are retracted from the peripheral end surface of the wafer W, so that the peripheral edge portion of the wafer W is landed on the wafer support portion 95a while being guided by the inclined surface below the wafer receiving portion 97. Thus, the holding of the wafer W by the auxiliary holding members S1 to S3 is released.

  Next, the control device 100 drives the first motor M <b> 1 to raise the first non-rotating side movable member 168 against the spring force of the compression coil spring 93. Thereby, the 1st rotation side movable member 181 is pushed up, and rotation of the positioning holding members F1-F3 arises according to the effect | action of 1st operation | movement conversion mechanism FT2. Thereby, those contact portions 96 are retracted from the peripheral end surface of the wafer W. Accordingly, the peripheral edge portion of the wafer W is landed on the wafer support portion 95 a while being guided by the lower inclined surface of the wafer receiving portion 97. Thus, the holding by the positioning holding members F1 to F3 is released.

Thereafter, the wafer W on the spin chuck 1 is unloaded by the substrate transfer robot. If there is an unprocessed wafer W to be further processed, the same processing is repeated.
As described above, also in this embodiment, after the wafer W is positioned and clamped in the three directions by the first holding member group F including the three positioning holding members F1 to F3, another three auxiliary holding members are used. The wafer W is supplementarily clamped by the second holding member group S composed of S1 to S3. Accordingly, as in the case of the first embodiment described above, the wafer W can be positioned and held on the rotation axis of the spin chuck 1 with high accuracy.

Also in this embodiment, since the holding by the three positioning holding members F1 to F3 is released after the holding of the wafer W by the three auxiliary holding members S1 to S3 is released, the wafer W is accurate. The wafer W can be released from being clamped in a well-positioned state. As a result, it is possible to satisfactorily carry out the wafer W by the substrate transfer robot.
Furthermore, since the holding of the wafer W is released in stages, the wafer W held at a small distance above the wafer support portion 95a of the holding members F1 to F3 and S1 to S3 falls at once. There is nothing. Thereby, generation | occurrence | production of the particle resulting from an impact, the defect | deletion of the wafer W, and the fall of the wafer W from the spin chuck 1 can be suppressed or prevented.

  While the two embodiments of the present invention have been described above, the present invention can also be implemented in other forms. For example, in the first embodiment described above, a height difference of a step Δh is provided in the height of the lower surface between the first interlocking ring 34 and the second interlocking ring 44, whereby the positioning and holding member F1. ~ F3 and the auxiliary holding members S1 to S3 are caused to have a time difference in the opening / closing operation. However, the same operation is possible without providing a step Δh at the height of the lower surfaces of the first and second interlocking rings 34 and 44. For example, a step may be formed on the contact surface 54 of the drive ring 52. That is, while the heights of the lower surfaces of the first and second interlocking rings 34 and 44 are made equal, the height of the portion of the contact surface 54 that faces the first interlocking ring 34 is set to be the second interlocking ring 44. What is necessary is just to make it lower than the height of the part which opposes. Moreover, you may vary the attachment angle of the plate-shaped part 95 with respect to the axis | shaft 35 between positioning holding member F1-F3 and auxiliary | assistant holding member S1-S3. That is, for example, while the first and second interlocking rings 34 and 44 are operated simultaneously, the contact portion 96 of the positioning holding members F1 to F3 is more than the contact portion 96 of the auxiliary holding members S1 to S3. The attachment angle of the plate-like portion 95 may be adjusted so that it is located slightly inward (closer to the rotation shaft 25).

  In the first and second embodiments described above, the configuration including the three positioning holding members F1 to F3 and the three auxiliary holding members S1 to S3 has been described. The configuration may include one or two auxiliary holding members, or may include three positioning holding members and four or more auxiliary holding members. Further, the auxiliary holding member does not have to hold / release the wafers W at once, and may operate to hold / release the wafers W one by one, or in a group unit including at least one auxiliary holding member, You may operate | move so that a time interval may be opened and pinched / released.

  Furthermore, a problem caused by dropping the wafer W when releasing the holding of the wafer W can be suppressed or prevented by sequentially releasing the holding of the peripheral edge of the wafer W by four or more holding members. That is, for example, when the peripheral portion of the wafer W is held by four holding members, the holding of the wafers W by the four holding members may be released one by one, for example. You may release them one by one. Of course, the number of holding members may be five or more.

  For example, by modifying the configuration of the first embodiment described above, six interlocking rings corresponding to each of the six holding members F1 to F3 and S1 to S3 are provided concentrically around the rotation shaft 25, and The height of the lower surface of the interlocking ring is varied by a minute height, and the drive ring having a horizontal contact surface facing these is moved up and down below the six interlocking rings. Conceivable. As a result, the holding / releasing of the wafer W by the six holding members can be generated with the timing shifted.

In the above-described second embodiment, the first and second non-rotating side movable members 168 and 178 are moved up and down by the motors M1 and M2 and the ball screw mechanisms 161 and 162. The first and second non-rotating side movable members 168 and 178 can be moved up and down using a mechanism.
In the above-described embodiment, the semiconductor wafer is taken as an example of the substrate to be processed. However, the present invention is applicable to other circular substrates such as an optical disk and rectangular substrates such as a glass substrate for a liquid crystal display device. Is also applicable.

  In addition, various design changes can be made within the scope of matters described in the claims.

It is an illustration for demonstrating the structure of the substrate processing apparatus which concerns on one Embodiment of this invention. It is a top view of the spin chuck with which the above-mentioned substrate processing device was equipped. It is a perspective view for demonstrating arrangement | positioning of the motion conversion mechanism with which the spin base was equipped. It is a perspective view for demonstrating arrangement | positioning of the motion conversion mechanism similarly provided in the spin base. It is a longitudinal cross-sectional view of a spin chuck. It is a perspective view for demonstrating the structure of the sequential operation mechanism for operating a positioning holding member and an auxiliary holding member in order. It is a perspective view for demonstrating the structure of the sequential operation mechanism for operating a positioning holding member and an auxiliary holding member in order similarly. It is a perspective view for demonstrating the structure of the up-and-down drive mechanism with which the sequential operation mechanism was equipped. It is a perspective view for demonstrating the structure of the link mechanism for operating a holding member. It is a side view for demonstrating the structure of a holding member. It is a block diagram for demonstrating the structure relevant to control of the said substrate processing apparatus. It is sectional drawing for demonstrating the structure relevant to the spin chuck of the substrate processing apparatus which concerns on 2nd Embodiment of this invention (XII-XII sectional view taken on the line of FIG. 13). It is a top view for demonstrating the structure of the drive mechanism for driving a holding member in the said 2nd Embodiment. It is a top view for demonstrating the structure of the 1st and 2nd non-rotation side movable member driven by the drive mechanism of FIG. It is a perspective view for demonstrating the structure of the operation | movement conversion mechanism which converts the driving force transmitted from the said 1st and 2nd non-rotation side movable member into operation | movement of a holding member. It is a perspective view for demonstrating the structure of the other part of a motion conversion mechanism. It is a partial expanded sectional view for demonstrating the structure for detecting the height of the 1st and 2nd interlocking ring interlock | cooperated with a holding member. It is a block diagram for demonstrating the electrical structure of the substrate processing apparatus of the said 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spin chuck 2 Motor 3 Process liquid supply pipe 4 Pure water supply valve 5 Etching liquid supply valve 6 Blocking plate 7 Lifting drive mechanism 8 Arm 9 Rotation drive mechanism 10 Nitrogen gas supply valve 11 Nitrogen gas supply pipe 12 Pure water supply valve 21 Spin Base 22 Upper plate 23 Lower plate 24 Through hole 25 Rotating shaft 26 Center shaft nozzle 26a Discharge port 27 Casing 27a Upper lid portion 28 Cover member 29 Seal mechanism 30 Seal member 31-33 Link mechanism 34 First interlocking ring 35 Shaft 36 Lever 36a Pin 37 Oscillating plate 37a Elongated hole 38 Crank member 38a Shaft portion 39 Lever 39a Bearing portion 40 Crank member 40a, 40b Shaft portion 41-43 Link mechanism 44 Second interlocking ring 45 Bearing member 46 Elevating member 46a Elongated hole 47 Guide shaft 48 Bush 49 Guide shaft DESCRIPTION OF SYMBOLS 0 Mechanism part accommodation space 51 Sequential actuating mechanism 52 Drive ring 53 Resin plate 54 Contact surface 55 Vertical drive mechanism 56 Base 57 Linear bushing 57A Main body part 57B Shaft part 58 Rotating ring 59 Air cylinder 59A Cylinder main body 59B Rod 60 Cam mechanism 61 Fixed Tube 61a Flange 62 Bearing 63 Long hole 65 Joint 66 Link block 67 Shaft 70 Cam block 71 Cam follower 72 Cam groove 73 Cam surface 92 Bush 93, 94 Compression coil spring 95 Plate-like portion 95a Wafer support portion 96 Contact portion 97 Wafer receiving portion 97 DESCRIPTION OF SYMBOLS 100 Control apparatus 100M Memory | storage part 101 1st digitization process part 102 2nd digitization process part 151 Gear case 152,153 Bearing 154 1st gear 155 2nd gear 156,157 Pinion 161 1st ball screw mechanism 62 Second ball screw mechanism 163 Screw shaft 164 Ball nut 165 Bearing portion 166 Gear 167 Guide shaft 168 First non-rotating side movable member 168a Recessed portion 169, 170 Protruding portion 171 First bearing 171f Non-rotating side ring 171r Rotating side ring 172 Bearing 172f Non-rotating side ring 172r Rotating side ring 177 Guide shaft 178 Second non-rotating side movable member 179,180 Protruding portion 181 First rotating side movable member 181a Shoulder portion 182 Second rotating side movable member 182a Screw hole 191 Guide rail 192 Guide Pin 192a Screw part 193 Bush 194 Through hole 197, 198 Position sensor F First holding member group F1-F3 Positioning holding member S Second holding member group S1-S2 Auxiliary holding member FT1 First motion conversion mechanism FT2 Second motion conversion mechanism La Floodlight Part Lb light receiving part M1 first motor M2 second motor W wafer Δh step

Claims (9)

At least four holding members that respectively abut against different positions on the edge of the substrate and cooperate to hold the substrate;
Holding member driving means for driving the at least four holding members when holding and releasing the substrate,
The at least four holding members are classified into a plurality of groups each including at least one holding member;
The holding member driving means drives the holding members of each group while shifting the timing from the holding members of at least one other group when holding or releasing the substrates. The at least four holding members are configured to be able to abut on different positions on the peripheral end surface of the substrate,
The plurality of groups include a first group of three positioning holding members capable of positioning and holding the substrate, and a second group of holding members other than the three positioning holding members,
The holding member driving means holds the substrate by the three positioning holding members constituting the first group when holding the substrate, and thereafter holds the holding member of the second group by the three positioning holding members. The substrate holding device according to claim 1, wherein the substrate holding device is brought into contact with a substrate held by a member.   The holding member driving means separates the second group of holding members from the substrate when releasing the holding of the substrate, and then separates the three positioning holding members constituting the first group from the substrate. The substrate holding apparatus according to claim 2, wherein The at least four holding members are configured to be able to abut on different positions on the peripheral end surface of the substrate,
The plurality of groups include a first group of three positioning holding members capable of positioning and holding the substrate, and a second group of holding members other than the three positioning holding members,
The holding member driving means separates the second group of holding members from the substrate when opening the substrates held by the at least four holding members, and thereafter, the three members constituting the first group The substrate holding apparatus according to claim 1, wherein the positioning holding member is separated from the substrate.   The at least four holding members are configured to move to a holding position while lifting the substrate when contacting the substrate, and to move to an open position while allowing the substrate to descend due to its own weight when separating from the substrate. The substrate holding device according to any one of claims 1 to 4.   The said holding member drive means includes a plurality of actuating members respectively connected to the holding members of each group, and sequential actuating means for actuating the plurality of actuating members in order. A substrate holding apparatus according to the above. The plurality of actuating members are provided to be displaceable between a holding position corresponding to a state where the holding member holds the substrate and an open position corresponding to a state where the holding member is separated from the substrate. ,
The sequential actuating means is for displacing the actuating member between a holding position and an open position, and includes a driving force transmission member capable of giving a driving force in common to the actuating members of the individual groups,
The substrate holding apparatus according to claim 6, wherein engagement or disengagement of the driving force transmission member and each of the plurality of groups of operation members occurs at intervals of time.   The substrate holding according to claim 7, wherein a stroke of the driving force transmitting member from the disengaged state to the engaged state of the driving force transmitting member and the plurality of operating members is different for each operating member. apparatus. A rotating base that supports the at least four holding members;
A rotation drive mechanism for rotating the rotation base;
Control means for controlling the rotation driving mechanism and the holding member driving means, and operating the holding member driving means in a state where the rotation driving mechanism is stopped and rotation of the rotation base is stopped. The substrate holding device according to any one of 1 to 8.