JP7731214B2 - Substrate gripping device - Google Patents

Description

The present invention relates to a substrate gripping device.

Patent Document 1 below discloses a substrate gripping device that can be used in cleaning and drying devices for substrates such as semiconductor wafers. This substrate gripping device is equipped with substrate holding parts (claws) that open and close in conjunction with the elevation of a support column. In a first embodiment, the substrate holding part opens and closes just before the elevation of the support column stops. In a second embodiment, the substrate holding part opens and closes just after the elevation of the support column begins.

JP 2014-133642 A

However, if the board holder is opened or closed just before the support column finishes rising, or in the short time immediately after the support column starts rising, the board holder opens and closes quickly, causing a large impact when it comes into contact with the board, leading to wear on the board holder.

The present invention was made in consideration of the above problems, and aims to provide a substrate gripping device that can reduce wear on the substrate holding portion.

A substrate gripping device according to one aspect of the present invention comprises a substrate holding unit that is movable between a closed state in which a substrate is clamped and an open state in which the clamped substrate is released, a support column that supports the substrate holding unit and is capable of moving up and down, and a linkage mechanism that links the lifting and lowering movement of the support column with the opening and closing movement of the substrate holding unit, wherein the range of opening and closing movement of the substrate holding unit during the lifting and lowering stroke of the support column includes at least a portion of the intermediate region of the lifting and lowering stroke.

In the above-mentioned substrate gripping device, the opening and closing range of the substrate holder may be 50% or more of the lifting stroke.

In the above-mentioned substrate gripping device, the opening and closing operation range of the substrate holder does not have to include the lower end of the lifting stroke.

In the above-mentioned substrate gripping device, the opening and closing operation range of the substrate holder does not have to include the upper end of the lifting stroke.

According to one aspect of the present invention, a substrate gripping device can be provided that can reduce wear on the substrate holder.

1 is a vertical cross-sectional view of a substrate gripping device according to an embodiment. FIG. 2 is a longitudinal cross-sectional view of a chuck according to an embodiment. 10A and 10B are explanatory views illustrating a closing operation of a substrate holding part according to an embodiment. 10A and 10B are explanatory diagrams illustrating the movement of the substrate guide member in conjunction with the closing operation of the substrate holder according to the embodiment. 10A and 10B are explanatory views illustrating an opening operation of a substrate holder according to an embodiment. 10A and 10B are explanatory diagrams illustrating the movement of the substrate guide member in conjunction with the opening operation of the substrate holder according to the embodiment. FIG. 10 is a diagram showing a state in which the chuck according to the embodiment has risen to a substrate transfer position. 10A and 10B are diagrams illustrating a state in which a chuck according to an embodiment is rising to a substrate transfer position. 10A and 10B are explanatory diagrams illustrating timings of lifting and lowering operations and opening and closing operations of a chuck according to an embodiment. 10 is a graph showing the timing of the lifting and lowering operation of the support column and the opening and closing operation of the substrate holder according to one embodiment. 10 is a graph showing the timing of the lifting and lowering operation of the support column and the opening and closing operation of the substrate holder 30 according to a modified example of the embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a vertical cross-sectional view of a substrate gripping device 1 according to an embodiment.
As shown in FIG. 1, the substrate gripping device 1 includes a base 2 and a plurality of chucks 3 (four in this embodiment (two of the four are not shown)) supported by the base 2.

The base 2 is fixed to the upper end of the rotating shaft 4. The rotating shaft 4 is supported by multiple bearings 5 so that it can rotate freely around an axis extending in the vertical direction. The multiple bearings 5 are fixed to the inner surface of a cylindrical body 6 that is arranged to surround the rotating shaft 4. The cylindrical body 6 is attached to a mount (not shown) and its position is fixed.

The rotating shaft 4 is connected to a motor 10 via pulleys 7 and 8 and a belt 9. The motor 10 rotates the base 2 via the pulleys 7 and 8 and the belt 9. A plurality of chucks 3 supported on the base 2 grip a substrate W such as a wafer. The substrate W is gripped at its peripheral edge by the plurality of chucks 3 and rotated around the rotating shaft 4 by the motor 10.

A lift mechanism 11 is disposed around the cylindrical body 6. The lift mechanism 11 is slidable up and down relative to the cylindrical body 6. The lift mechanism 11 has multiple pushers 12 that contact the lower ends of the multiple chucks 3 and lift these chucks 3. The lift mechanism 11 is connected to an air-driven lifting device (not shown) and moves up and down together with the multiple pushers 12.

The multiple chucks 3 are fixed to a ring member 13. The ring member 13 raises and lowers the multiple chucks 3 synchronously and as a unit. The ring member 13 extends in an annular shape along the arrangement direction of the chucks 3 and is located below the base 2. The ring member 13, rotation shaft 4, base 2, and cylindrical body 6 are arranged concentrically.

A rotating cup 14 is fixed to the upper surface of the base 2. The rotating cup 14 catches liquid that is ejected from the rotating substrate W due to centrifugal force. The rotating cup 14 is arranged to surround the entire periphery of the substrate W. The vertical cross-sectional shape of the rotating cup 14 is inclined radially inward. The inner peripheral surface of the rotating cup 14 is composed of a smoothly curved surface.

FIG. 2 is a vertical cross-sectional view of the chuck 3 according to one embodiment.
2, each chuck 3 includes a substrate holder 30 that is movable between a closed state in which the substrate W is clamped and an open state in which the clamped substrate W is released, a support column 40 that supports the substrate holder 30 and is movable up and down, and an interlocking mechanism 50 that interlocks the lifting and lowering operation of the support column 40 with the opening and closing operation of the substrate holder 30.

The base 2 includes a fixed plate 21 and a spring retainer 22. The fixed plate 21 and the spring retainer 22 have through-holes formed therein, allowing the support column 40 to slide vertically. The diameter of this through-hole is slightly larger than the diameter of the support column 40, allowing the chuck 3 to move vertically relative to the base 2.

The substrate holders 30 have an inclined surface 31 that slopes downward toward the inside in the radial direction of the substrate W. Claws 32 are formed on the inclined surface 31 and come into contact with the peripheral edge of the substrate W. The peripheral edge of the substrate W is first placed on the inclined surface 31 and then gripped by the claws 32. The substrate holders 30 are arranged at equal intervals around the central axis of the base 2 and the rotation shaft 4. Therefore, by the substrate holders 30 gripping the peripheral edge of the substrate W, the substrate W can be automatically centered.

The support column 40 is formed in a cylindrical shape extending in the vertical direction. The ring member 13 (see Figure 1) described above is fixed to the support column 40. A flange 41 that can be placed on the fixed plate 21 is provided near the upper end of the support column 40. A support shaft 42 that rotatably supports the substrate holder 30 is provided at the upper end of the support column 40 above the flange 41.

A spring retainer 43 is fixed to the lower end of the support column 40. A primary spring 44 is disposed between the spring retainer 22 on the base 2 side and the spring retainer 43 on the support column 40 side. This primary spring 44 is a compression spring that biases the support column 40 downward relative to the base 2.

The interlocking mechanism 50 includes a rod 51 housed inside the support column 40. The rod 51 is arranged so that it can move freely up and down within the support column 40. An elongated hole 52 is formed at the upper end of the rod 51. A pin 33 provided on the substrate holder 30 is displaceably engaged with the elongated hole 52.

A spring retainer 53 is fixed to the lower end of the rod 51. A secondary spring 54 is positioned between the spring retainer 53 of the rod 51 and a step formed on the inner surface of the support column 40. The secondary spring 54 is a compression spring that urges the rod 51 downward relative to the support column 40. The spring constants and free lengths of the primary spring 44 and secondary spring 54 are adjusted so that the board holder 30 opens and closes at the timing described below.

FIG. 3 is an explanatory diagram illustrating the closing operation of the substrate holder 30 according to one embodiment.
3, when the rod 51 descends relative to the support column 40, the pin 33 engaged with the long hole 52 of the rod 51 descends, causing the substrate holder 30 to rotate about the support shaft 46. The direction of rotation of the substrate holder 30 at this time is the direction in which the claws 32 approach the peripheral edge of the substrate W. The peripheral edge of the substrate W is gripped by the claws 32, thereby clamping the substrate W.

FIG. 4 is an explanatory diagram illustrating the movement of the substrate guide member 55 in conjunction with the closing operation of the substrate holder 30 according to one embodiment.
4, the interlocking mechanism 50 includes a substrate guide member 55 for guiding the substrate W transferred from the transfer device to the substrate holder 30. The substrate guide member 55 is fixed to the rod 51 by a screw 55. Therefore, the substrate guide member 55 moves up and down integrally with the rod 51 relative to the support column 40.

The substrate guide member 55 descends in synchronization with the closing operation of the substrate holder 30, and its upper end becomes lower than the substrate holder 30. With this configuration, liquid supplied to the upper surface of the rotating substrate W can be discharged from the peripheral edge of the substrate W by centrifugal force without being disturbed by the substrate guide member 55. In other words, it is possible to eliminate liquid splashing from the substrate guide member 55.

FIG. 5 is an explanatory diagram illustrating the opening operation of the substrate holder 30 according to one embodiment.
5, when the rod 51 rises relative to the support column 40, the pin 33 engaged with the long hole 52 of the rod 51 descends, causing the substrate holder 30 to rotate about the support shaft 46. The direction of rotation of the substrate holder 30 at this time is the direction in which the claws 32 move away from the peripheral edge of the substrate W. When the claws 32 move away from the peripheral edge of the substrate W, the clamping of the substrate W is released.

FIG. 6 is an explanatory diagram illustrating the movement of the substrate guide member 55 in conjunction with the opening operation of the substrate holder 30 according to one embodiment.
6 , the substrate guide member 55 rises in synchronization with the opening operation of the substrate holding part 30, and its upper end becomes higher than the substrate holding part 30. A tapered surface is formed at the upper end of the substrate guide member 55 for guiding the peripheral edge of the substrate W to the inclined surface 31 of the substrate holding part 30. With this configuration, the peripheral edge of the substrate W transferred from the transport device can be guided by the tapered surface of the substrate guide member 55 and moved to the inclined surface 31 of the substrate holding part 30.

Next, we will explain the timing of the opening and closing operations of the substrate holder 30 configured as described above.

FIG. 7 is a diagram showing a state in which the chuck 3 according to an embodiment has been raised to a position for transferring the substrate W.
7, the substrate holding part 30 is open when the chuck 3 is raised to the transfer position for the substrate W. In other words, the substrate holding part 30 is open at the upper end of the lifting stroke S of the support part 40.

FIG. 8 is a diagram showing the state in which the chuck 3 according to the embodiment is rising to the transfer position for the substrate W.
8, the substrate holder 30 is open while the chuck 3 is rising to the transfer position for the substrate W. The elevation height S1 of the support column 40 at this time is approximately 60% to 70% of the elevation stroke S of the support column 40 shown in FIG.

FIG. 9 is an explanatory diagram illustrating the timing of the lifting and lowering operation and the opening and closing operation of the chuck 3 according to one embodiment.
When the chuck 3 rises to the transfer position for the substrate W, the pusher 12 of the lift mechanism 11 pushes up the rod 51. When the rod 51 is pushed up, an upward force is applied to the support column 40 via the secondary spring 54. As a result, the support column 40 and the rod 51 rise together.

The positions of both ends of the line shown in Figure 9 indicate the clamped position, i.e., the state in which the support column 40 and rod 51 are both at their lowest positions. At this time, the repulsive force of the primary spring 44 is slightly smaller than the repulsive force of the secondary spring 54. When the pusher 12 pushes up on the rod 51, the primary spring 44 begins to compress first. In other words, at this time, the length of the secondary spring 54 does not change, and the substrate holder 30 remains in a closed state.

As shown in Figure 9, when the chuck 3 has risen by X1 mm (several mm), the secondary spring 54 also begins to compress. As the repulsive forces of the primary spring 44 and secondary spring 54 balance each other, the primary spring 44 and secondary spring 54 simultaneously compress from the X1 mm position to the X2 mm position (lifting height S1). During this time, the substrate holder 30 gradually opens. The X2 mm position is approximately 60-70% of the lifting stroke. When the chuck 3 reaches the X2 mm position, the substrate holder 30 enters an open state, and the secondary spring 54 fully compresses. From this point on, only the primary spring 44 compresses, and the chuck 3 reaches the substrate W transfer position (X3 mm (the upper end of the lifting stroke S)).

The same applies when the chuck 3 is lowered. When the chuck 3 moves from the substrate W transfer position to the clamping position (0 mm position), the pusher 12 of the lift mechanism 11 is lowered. When the pusher 12 is lowered, a downward force is applied to the support column 40 via the primary spring 44. As a result, the support column 40 and rod 51 are lowered together.

When the chuck 3 descends from the substrate W transfer position (X3 mm) and reaches the X2 mm position (lift height S1), the secondary spring 54 also begins to extend. Then, from the X2 mm position to the X1 mm position, the primary spring 44 and secondary spring 54 extend simultaneously. When the chuck 3 reaches X1 mm, the secondary spring 54 is fully extended and the substrate holder 30 enters a closed state. From this point on, only the primary spring 44 extends, and the chuck 3 reaches the clamp position (0 mm).

FIG. 10 is a graph showing the timing of the lifting and lowering operation of the support column 40 and the opening and closing operation of the substrate holder 30 according to one embodiment.
10, the substrate holding unit 30 is in a closed state at the bottom end of the lifting stroke S, but begins to gradually open as the support unit 40 rises slightly from the bottom end of the lifting stroke S. The opening and closing operation of the substrate holding unit 30 continues even after the middle of the lifting stroke S, and ends when the substrate holding unit 30 reaches a lifting height S1, which is approximately 60 to 70% of the lifting stroke S.

In this way, the opening and closing operation range A of the substrate holding unit 30 during the lifting and lowering stroke S of the support unit 40 includes at least a portion of the intermediate region M of the lifting and lowering stroke S. The intermediate region M refers to the middle region when the lifting and lowering stroke S is divided into three equal parts. In this way, by having the substrate holding unit 30 open and close over a long period of time so as to include at least a portion of the intermediate region M of the lifting and lowering stroke S, the opening and closing speed of the substrate holding unit 30 is slowed and the impact when it comes into contact with the substrate W is reduced, resulting in reduced wear on the substrate holding unit 30.

As such, the substrate gripping device 1 according to this embodiment comprises a substrate holder 30 that is movable between a closed state in which the substrate W is clamped and an open state in which the substrate W is released from the clamp; a support column 40 that supports the substrate holder 30 and is capable of raising and lowering; and an interlocking mechanism 50 that interlocks the raising and lowering movement of the support column 40 with the opening and closing movement of the substrate holder 30. The opening and closing movement range A of the substrate holder 30 during the raising and lowering stroke S of the support column 40 includes at least a portion of the intermediate region M of the raising and lowering stroke S. With this configuration, the opening and closing movement of the substrate holder 30 takes a long time, thereby reducing wear on the substrate holder 30. Furthermore, because the opening and closing movement of the substrate holder 30 is performed during the raising and lowering movement of the support column 40, substrate processing throughput does not decrease even if the opening and closing movement of the substrate holder 30 is slowed.

Furthermore, in this embodiment, the opening and closing operation range A of the substrate holding unit 30 is 50% or more of the lifting and lowering stroke S. With this configuration, the substrate holding unit 30 opens and closes slowly over 50% or more of the lifting and lowering stroke S, which sufficiently slows down the opening and closing speed of the substrate holding unit 30. This reduces the impact when it comes into contact with the substrate W, and ensures that wear on the substrate holding unit 30 is suppressed.

Furthermore, in this embodiment, the opening/closing operation range A of the substrate holder 30 does not include the lower end of the lifting stroke S. This configuration more reliably suppresses wear on the substrate holder 30. In other words, since vibrations are large immediately after the support columns 40 begin to rise, it is preferable to keep the substrate holder 30, which is the part that comes into contact with the substrate W, closed. This prevents the substrate W from shifting out of position. Furthermore, immediately after the support columns 40 begin to rise, there is an acceleration time before they reach a constant speed, and vibrations are likely to increase due to individual differences in parts as well.

Furthermore, in this embodiment, the opening/closing operation range A of the substrate holder 30 does not include the upper end of the lifting stroke S. This configuration more reliably suppresses wear on the substrate holder 30. In other words, vibrations are also likely to occur when the support column 40 begins to descend. When the support column 40 descends and the substrate holder 30 closes (relative movement between the support column 40 and the substrate holder 30), vibrations are superimposed. Therefore, when the substrate holder 30 begins to descend, it is better to leave the substrate holder 30 in an open state (fully open) and have only the support column 40 descend. By keeping the substrate holder 30 in an open state (fully open) when the descent begins, when vibrations are likely to occur, static friction between the substrate W and the position where the substrate W is placed is maintained, which can be said to be desirable.

While preferred embodiments of the present invention have been described and illustrated above, it should be understood that these are illustrative of the present invention and should not be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present invention. Accordingly, the present invention should not be deemed limited by the foregoing description, but rather by the scope of the claims.

For example, the substrate holder 30 may be opened and closed at the timing shown in FIG.
FIG. 11 is a graph showing the timing of the lifting and lowering operation of the support column 40 and the opening and closing operation of the substrate holder 30 according to a modified example of the embodiment.
11 , the substrate holding unit 30 may have an opening/closing operating range A1 that includes at least a part of the intermediate region M of the lifting/lowering stroke S and operates in the latter half (upper half) of the lifting/lowering stroke S. Alternatively, the substrate holding unit 30 may have an opening/closing operating range A2 that includes the entire intermediate region M of the lifting/lowering stroke S and operates in the intermediate part of the lifting/lowering stroke S.

1 Substrate gripping device 2 Base 3 Chuck 4 Rotating shaft 5 Bearing 6 Cylinder 7 Pulley 8 Pulley 9 Belt 10 Motor 11 Lift mechanism 12 Pusher 13 Ring member 14 Rotating cup 21 Fixing plate 30 Substrate holding portion 31 Inclined surface 32 Claw portion 33 Pin 40 Support portion 41 Flange 42 Support shaft 44 Primary spring 46 Support shaft 50 Interlocking mechanism 51 Rod 52 Elongated hole 54 Secondary spring 55 Substrate guide member A Opening/closing operation range A1 Opening/closing operation range A2 Opening/closing operation range M Intermediate region S Lifting stroke W Substrate

Claims (4)

a substrate holder that is movable between a closed state in which the substrate is clamped and an open state in which the substrate is released from the clamp;
a support column that supports the substrate holder and is capable of moving up and down;
a linkage mechanism that links the lifting and lowering operation of the support column with the opening and closing operation of the substrate holder,
A substrate gripping device, characterized in that the opening and closing operation range of the substrate holding part during the lifting and lowering stroke of the support part includes at least a part of an intermediate region of the lifting and lowering stroke, but does not include a lower end of the lifting and lowering stroke . The substrate gripping device described in claim 1, characterized in that the opening and closing range of the substrate holder is 50% or more of the lifting stroke. 3. The substrate gripping device according to claim 1 , wherein the opening and closing range of the substrate holder does not include the upper end of the lifting stroke. a substrate holder that is movable between a closed state in which the substrate is clamped and an open state in which the substrate is released from the clamp;
a support column that supports the substrate holder and is capable of moving up and down;
a linkage mechanism that links the lifting and lowering operation of the support column with the opening and closing operation of the substrate holder,
A substrate gripping device, characterized in that the opening and closing operation range of the substrate holding part during the lifting and lowering stroke of the support part includes at least a part of an intermediate region of the lifting and lowering stroke, but does not include an upper end of the lifting and lowering stroke.