KR100859933B1 - Substrate holding device - Google Patents

Abstract

A substrate holder (1) formed in a frame shape having an opening and adsorbing and holding a circumferential edge of the glass substrate (4), and installed at a predetermined position in the opening of the substrate holder, and having a suction substrate holding the glass substrate. A suction member 20 is provided.

Description

Substrate holding device {SUBSTRATE HOLDING DEVICE}

The present invention relates to a substrate holding apparatus for holding a large glass substrate of a flat panel display (FPD) such as a liquid crystal display or an organic EL display.

Japanese Patent Application Laid-Open No. 2000-7146 describes a glass substrate holding mechanism for holding a glass substrate (a semiconductor device substrate including a plastic substrate) of a flat panel display (FPD) such as a liquid crystal display or an organic EL display. have. The glass substrate holding mechanism comprises a holding frame for adsorption and holding the glass substrate, a transparent member for blocking the opening of the transmission frame of the holding frame, and a plurality of glass pins mounted on the upper surface of the transparent member to support the glass substrate. A substrate holding mechanism is described.

In this glass substrate holding mechanism, a thin glass substrate is placed on a plurality of support pins, and only the periphery of the glass substrate is adsorbed and held on the holding frame. The central part bends or vibrates.

In addition, the substrate holding apparatus shown in FIG. 10 has been proposed in association with the enlargement of the glass substrate. The substrate holder 1 is formed in a frame shape. In the opening of the substrate holder 1, a plurality of holding tables 2 of respective pillars are provided. On the upper surface of these holding tables 2, a plurality of support pins 3 are arranged in a row at fixed intervals and fixed.

A plurality of suction members (adsorption pads) 5 are provided at the edges of the frame portion of the substrate holder 1 for suction-holding the glass substrate 4. These suction members 5 are connected to a suction tube (not shown), and perform suction by receiving suction of the suction pump. In addition, a plurality of reference pins 6 and a plurality of pressing pins 7 are provided at the periphery of the frame portion of the substrate holder 1.

In performing the surface inspection of the glass substrate 4, the glass substrate 4 is placed on the substrate holder 1, pressed by the plurality of pressing pins 7 to the plurality of reference pins 6, and placed at the reference position. Is set. Thereafter, the glass substrate 4 is sucked and fixed on the substrate holder 1 by the plurality of suction members 5.

However, there is a case where the thin glass substrate 4 is lifted to the central portion of the glass substrate 4 where the pressing pin 7 is pressed against the reference pin 6. In addition, when the substrate holder 1 is swung for macro inspection, the central portion of the glass substrate 4 is shaken in the vertical direction to vibrate greatly, or the vibration occurs in the central portion of the glass substrate 4 due to the downflow of the clean room. have.

As such, when the central portion of the glass substrate 4 is shaken in the vertical direction and vibrates greatly, the defect is shaken, making it difficult to observe. In the case of observing the glass substrate 4 by using a microscope, if the glass substrate 4 is floating, the distance between the objective lens and the surface of the glass substrate 4 changes when the observation position of the microscope is vibrated, and the focus shift occurs. This happens. In addition, when observing under a microscope, if vibration occurs in the glass substrate 4, there is a problem that the autofocus cannot be achieved until the vibration is stabilized.

In addition, when the vibration of the up and down direction is received, the back surface of the glass substrate 4 may come into contact with the support pins 3 and may be damaged. In addition, when the central portion of the glass substrate 4 is greatly shaken in the vertical direction due to the change of the wind pressure of the downflow, or the glass substrate 4 becomes thin, the support pin 3 is caused by the wind pressure of the automatic downflow of the glass substrate 4 itself. A slight warp may occur between the glass substrate 4 and the glass substrate 4. As a result, the horizontality of the glass substrate 4 cannot be maintained, and the focusing position is shifted at the time of micro observation by a microscope or the like.

On the other hand, when the metal pillars are used to increase the strength of the holding stand 2, the transmission illumination light by the penetrating spectroscopic method is blocked by the plurality of holding stands 2, and is projected as a shadow on the glass substrate 4 to be inspected. It causes trouble.

An object of the present invention is to provide a substrate holding apparatus that can prevent the lifting and vibration of the center portion of the substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate holding apparatus which can realize a good transmission speculum and can easily adjust the height of the support pin by suppressing the influence of the reduction of the amount of transmitted illumination light by the holding table installed on the substrate holder. .

According to a principal aspect of the present invention, there is provided a substrate holder which is formed in a frame shape having an opening and adsorbs and holds a peripheral edge of the substrate, and a substrate suction member which is installed at a predetermined position in the opening of the substrate holder to adsorb and hold the substrate. Provided is a substrate holding apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram of the board | substrate holding apparatus which shows 1st Embodiment of this invention.

Figure 2a is a top view of the attachment of the substrate suction member and the support pin to the holding table.

Figure 2b is a side view of the attachment of the substrate suction member and the support pin to the holding table.

Figure 3a is a top view of the attachment of the support pin to the holding table.

Figure 3b is a side view of the attachment of the support pin to the holding table.

4 is a cross-sectional view of the substrate suction member.

5 is a cross-sectional view of the support pin.

6 is a view for explaining a height adjustment method of a plurality of substrate suction member and the support pin.

Fig. 7 is a configuration diagram of an optical lens showing the second embodiment of the present invention.

8A is a diagram illustrating an example of a method of manufacturing an optical lens.

8B is a view showing an example of a method of manufacturing an optical lens.

8C is a diagram illustrating an example of a method of manufacturing an optical lens.

9 is a configuration diagram showing a modification of the substrate suction member.

10 is a schematic configuration diagram of a conventional substrate holding apparatus.

※ Explanation of symbols for main parts of drawing

1: Substrate Holder 4: Glass Substrate

10: holding table 10a, 10b: holding plate

11: space portion 20: substrate suction member                 

21: suction tube 22: substrate holding shaft

23: suction passage 24: adsorption member

25: suction hole 26: release prevention ring

27: attachment end 30: support pin

31: holding shaft 31a: screw

32; Recess 33: ball

34: Set screw 35: Contact groove

36: set screw 37: clearance groove

38: holding bearing 38a: screw hole

39, 40: flat part 43: reference block

44: reference plane 45: reference table

50: optical lens 50a: locking portion

51a, 51b: notch portion 52: cylindrical member

52a, 52b: lens member 60, 60a: substrate sucking member body

61, 61b: substrate holding shaft 62: screw groove

63: thread 64: O-ring

65: space part 66: fixing screw

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described with reference to drawings. In addition, the same parts as in FIG. 10 are denoted by the same reference numerals, and detailed description thereof will be omitted.                 

1 is a block diagram of a substrate holding apparatus. This substrate holding apparatus is applied to a surface inspection apparatus which inspects the surface of the glass substrate 4 of a flat panel display. In the opening of the substrate holder 1, a plurality of holding stands 10 are installed. These holding tables 10 are formed in a ladder shape, and are arranged at predetermined intervals between two opposite sides in the opening portion of the substrate holder 1. These holding tables 10 are composed of two strip-shaped holding plates 10a and 10b in which plate surfaces of each other face each other. Between these holding plates 10a and 10b, a space portion 11 for transmitting transmitted light is formed. The holding plates 10a and 10b have a width dimension sufficiently long with respect to the plate thickness and are made of metal with high rigidity. The holding plates 10a and 10b are coated with a dustproof material (high damping material) on the plate surface for the purpose of suppressing vibration, or the holding plates 10a and 10b are made of a damping metal such as grain boundary corrosion stainless steel. . As the dustproof material, polymer rubber, resin, vibration absorbing paint, or gel-like material may be used. Examples of the vibration absorbing paint include urethane, acrylic, and silicone resins. Examples of the gel-like substance include organogels, polymer gels, silicone gels, and fluorine ion exchange resins. Moreover, you may sandwich a transparent prevention material between two holding plates 10a and 10b. In addition, by changing the thickness of the holding plate (10a, 10b), or changing the thickness or mass of the dustproof material so that each holding table 10 does not vibrate, the holding table (10) It is desirable to eliminate resonance between each other.

A plurality of substrate sucking members 20 are provided at each holding table 10 corresponding to a predetermined position in the opening of the substrate holder 1, for example, the center portion. In addition, each holding base 10 is provided with a plurality of support pins 30.                 

2A and 2B are diagrams illustrating the attachment of the substrate suction member 20 and the support pins 30 to the holding table 10. FIG. 2A is a view from above and FIG. 2B is a side view. These substrate suction members 20 and the support pins 30 are sandwiched between two holding plates 10a and 10b at predetermined intervals. A suction tube 21 is connected to each substrate suction member 20. The suction tube 21 is disposed between two holding plates 10a and 10b. The suction tube 21 is formed of, for example, a light transmissive material. It is preferable that the bottom surfaces of the two holding plates 10a and 10b are formed of a light transmissive member.

3A and 3B are diagrams showing only the supporting pins 30 with respect to the holding table 10. FIG. 3A is a view from above and FIG. 3B is a side view. A plurality of support pins 30 are sandwiched at predetermined intervals between the two holding plates 10a and 10b.

4 is a cross-sectional view of the substrate suction member 20. A substrate holding shaft 22 is provided on the substrate suction member 20. A suction passage 23 is formed in the substrate holding shaft 22 in the axial direction. The front end portion of the substrate holding shaft 22 is attached so that the suction member 24 formed by the elastic material does not come off. The suction member 24 is provided with a suction hole 25 for communicating with the suction passage 23. The adsorption member 24 is held at the front end of the substrate holding shaft 22 by the release preventing ring 26. In addition, the suction tube 21 is attached to the lower portion of the substrate suction member 20 by an attachment end 27. The suction tube 21 is connected to the suction passage 23 by being attached to the substrate suction member 20. In addition, the suction tube 21 is connected to a suction pump P provided outside the substrate holder 1.

5 is a cross-sectional view of the support pin 30. The support pin 30 is provided with a cylindrical holding shaft 31. A recess 32 is formed at the tip end of the holding shaft 31, and a ball 33 is rotatably provided in the recess 32. On the original side of the holding shaft 31, a contact groove 35 for receiving the screw tightening of the fixing screw 34 and a clearance groove 37 for preventing the fixing screw 36 from contacting are formed. In addition, a screw 31a is formed in the holding shaft 31 below the clearance groove 37, and the holding shaft 31 is screwed into the screw hole 38a formed in the lower portion of the holding shaft support 38, Arrow is installed so as to be movable in a direction.

Therefore, the height of the support pin 30 is adjusted from the bottom opening of the holding shaft support 38 by moving the holding shaft 31 in the direction of the arrow while adjusting the height position by rotating the holding shaft 31 using a screwdriver, and then fixing the screw 34. Tightening is carried out by fixing the holding shaft 31 to the holding shaft support 38.

In the lower part of the holding bearing 38, each flat part 39, 40 for receiving two holding plates 10a, 10b is formed at both sides. The holding bearing 38 is provided with respective threaded holes 41 and 42 for passing through the fixing screws 34 and 36.

The support pin 30 having such a structure can be attached and detached between the two holding plates 10a and 10b by loosening the fixing screw 36, and is supported only by rotating the holding shaft 31. The height of the pin 30 can be adjusted.

Next, height adjustment of the plurality of substrate suction members 20 and the plurality of support pins 30 provided in the substrate holder 1 will be described with reference to FIG. 6.

The reference block 43 on which the reference plane 44 is formed is prepared. This reference plane 44 is a plane without any skew or irregularities. Each reference stage 45 is provided at both ends on the reference plane 44, respectively. These reference stages 45 are formed with reference heights H for adjusting the heights of the plurality of substrate suction members 20 and the plurality of support pins 30. These reference tables 45 are arranged at intervals suitable for the size of the substrate holder 1, and the holding tables 10 are placed upside down between the reference tables 45 and 45.

The height of the substrate suction member 20 and the support pin 30 may be placed on the reference plane 44.

In the height adjustment of the substrate suction member 20, since the suction member 24 at the distal end of the substrate holding shaft 22 shown in Fig. 4 is formed of an elastic material, the suction member 24 fits the reference plane 44. When it touches, it expands and contracts according to the height of the reference plane 44. In this state, the substrate suction member 20 is fixed to the holding plates 10a and 10b by two screws or the like.

On the other hand, the height adjustment of the support pin 30 inserts the holding shaft support 38 shown in FIG. 5 from a bottom opening, and rotates it until the ball 33 of the tip of the holding shaft 31 abuts on the reference plane 44. . After the height of the holding shaft 31 is adjusted, the fixing screw 34 is tightened to fix the holding shaft 31 to the holding shaft support 38.

As a result, the height positions of all the substrate suction members 20 and the support pins 30 are all gathered on the reference plane 44, and the height adjustment of these substrate suction members 20 and the support pins 30 is completed.

In addition, the height adjustment of only the plurality of support pins 30 is performed by vertically moving the respective holding shafts 31 of the respective support pins 30 as above.

Next, the operation of the device configured as described above will be described.                 

When performing the surface inspection of the glass substrate 4, the glass substrate 4 is pressed to each reference pin 6 by each pressing pin 7 and set in the reference position, and then the center of the glass substrate 4 first. The part is sucked and fixed by the reference suction member 20. Subsequently, the periphery of the glass substrate 4 is sucked and fixed on the substrate holder 1 by the suction pads 5.

When the suction pump P is suctioned, the plurality of substrate suction members 20 perform suction operations, respectively, and hold the glass substrate 4 at the center thereof. At the same time, the glass substrate 4 is supported by the plurality of support pins 30.

As a result, the glass substrate 4 is always held at the circumferential edge and the center thereof, so that the horizontal level is always maintained. Therefore, even if the substrate holder 1 is swung at the time of the macro inspection, even if it is affected by downflow or the like, no floating occurs in the center portion of the glass substrate 4.

Surface inspection is performed by the spectroscopic method using the permeation | transmission illumination or the fall-off illumination with respect to the glass substrate 4. In the spectroscopic method of transmission illumination, transmission illumination light is irradiated from the bottom of the glass substrate (4). At the temporary position of the holding table 10, the transmitted illumination light is irradiated onto the glass substrate 4 through the space 13 between the two holding plates 10a and 10b. At the same time, the transmitted illumination light enters from the circumference of each of the holding plates 10a and 10b, and the transmitted transmitted illumination light is irradiated onto the glass substrate 4. Even when the suction tube 21 is provided, the transmission illumination light is diffused by the light transmitting tube 21 and irradiated onto the glass substrate 4.

Therefore, even in the transmissive illumination system, the amount of transmitted illumination light irradiated onto the glass substrate 4 can be reduced even at the temporary position of the holding table 10, so that the decrease in the amount of light can be suppressed, so that the surface inspection of the glass substrate 4 can be performed well. Can be.

As described above, in the above-described embodiment, the plurality of substrate suction members 20 are attached to a portion corresponding to the center portion of the glass substrate 4 when the glass substrate 4 is placed on the substrate holder 1. The periphery is fixedly attracted by the respective suction members 5 of the periphery of the substrate holder 1 and the central part is fixedly sucked. As a result, the glass substrate 4 can be reliably held at a high horizontal level. Thereby, the surface inspection of the glass substrate 4 can be performed correctly, without an erroneous inspection occurring in the macro inspection of the glass substrate 4. Even when microscopic observation is performed at a high magnification by a microscope or the like, the distance between the objective lens and the surface of the glass substrate 4 is kept constant so that no deviation of the focus occurs and inspection can be performed by the image of the merged point on the entire surface of the glass substrate 4. have.

Since the plurality of substrate suction members 20 are sandwiched between two holding plates 10a and 10b, and the plurality of supporting pins 30 are also sandwiched between two holding plates 10a and 10b, the transmission illumination light Transmissive illumination light which is irradiated to the glass substrate 4 through the space portion 13 between the two holding plates 10a and 10b and turns from the circumference of these holding plates 10a and 10b to the glass substrate 4. Is investigated. In addition, the transmitted illumination light is diffused by the light transmitting suction tube 21 is irradiated to the glass substrate (4). As a result, a decrease in the amount of light of the transmitted illumination light irradiated onto the glass substrate 4 can be suppressed to a minimum, and a good transmission speculum can be realized.

Each holding plate 10a, 10b is easy to process, can shorten a manufacturing time, and can reduce cost.                 

Since the plurality of substrate suction members 20 can be attached and detached between the two holding plates 10a and 10b, they are attached to a desired position on a straight line of the two holding plates 10a and 10b. I can remove it. These board | substrate suction members 20 can arbitrarily adjust an arrangement | interval spacing according to the size and weight of the glass substrate 4.

The plurality of substrate suction members 20 and the plurality of support pins 30 may adjust all heights equally by using the reference block 43 and the respective reference bars 45. In this case, the substrate suction member 20 may adjust the height by the adsorption member 24 along the reference plane 44, and the support pin 30 may be adjusted by moving the holding shaft 31 up and down. Therefore, the glass substrate 4 can be reliably held at a high horizontal level.

The vibration of the holding table 10 can be reduced by coating the holding plates 10a and 10b with a dustproof material or by manufacturing a vibration damping metal and sandwiching the dustproof material in the gaps between the holding plates 10a and 10b. Therefore, the vibration of the glass substrate 4 placed on the support pin 30 can be suppressed.

Next, 2nd Embodiment of this invention is described with reference to drawings. In addition, the same parts as those in Figs. 1 to 6 are denoted by the same reference numerals and detailed description thereof will be omitted. As shown in FIG. 7, the optical lens 50 as an optical component for light scattering or diffusion is provided between two holding plates 10a and 10b as shown in FIG. .

This optical lens 50 is formed in an arcuate lens shape, and each engaging portion 50a is formed. As a result, the optical lens 50 is caught by the two holding plates 10a and 10b, and freely attaches and detaches to the holding plates 10a and 10b and does not fall from between the holding plates 10a and 10b. Do not. The optical lens 50 is not limited to an arcuate lens shape, but may be provided with a diffusion plate, a prism, a Fresnel lens, or the like.

The notches 51a and 51b are formed in the lower part of the two holding plates 10a and 10b toward each other inward. Each notch part 51a, 51b has a function which reflects a part of the transmission illumination light from the lower side between each holding plates 10a, 10b, respectively, and increases the light quantity of the transmission illumination light spread by the optical lens 50, respectively. .

Next, an example of a manufacturing method of the optical lens 50 will be described. First, a cylindrical member (lot, 52) formed of a light-transmissive resin (for example, plastic) as shown in Fig. 8A is divided into two longitudinally two lens members 52a and 52b as shown in Fig. 8B. ).

Next, both sides of each lens member 52a, 52b are cut, respectively, and two arcuate lens-shaped optical lenses 50 are manufactured.

If the lens members 52a and 52b can be inserted directly between the two holding plates 10a and 10b without cutting both sides of the lens members 52a and 52b, the lens members 52a and 52b are optically inserted. It may be used as the lens 50.

Next, the operation of the device configured as described above will be described.

When the surface inspection of the glass substrate 4 is carried out by the spectroscopic method of transmission illumination, the transmission illumination light irradiated from the lower side of the glass substrate 4 is applied to the optical lens 50 provided between the two holding plates 10a and 10b. Diffuses and irradiates the glass substrate 4. At the same time, the transmitted illumination light that hits the notches 51a and 51b of the two holding plates 10a and 10b is reflected by the notches 51a and 51b toward the two holding plates 10a and 10b, The light is diffused through the lens 50 and irradiated onto the glass substrate 4.

Therefore, even in the penetrating illumination method, even if the amount of light transmitted through the glass substrate 4 is irradiated at the temporary position of the holding table 10, the decrease in the amount of light can be reduced. Surface inspection of 4) becomes possible. Among them, part of the transmitted illumination light is reflected by the notches 51a and 51b and is incident between the two holding plates 10a and 10b, so that the amount of light of the transmitted illumination light irradiated onto the glass substrate 4 is increased than in the first embodiment. can do.

Thus, in the said 2nd Embodiment, since the optical lens 50 as an optical component for light scattering or diffusing is provided between the holding plates 10a and 10b of 2 sheets, the transmission illumination light is diffused by this optical lens 50, and glass is used. It is possible to irradiate the substrate 4, so that the reduction in the amount of light of the transmitted illumination light irradiated onto the glass substrate 4 can be suppressed to be small, and the range of the surface inspection of the glass substrate 4 in the speculative method of transmission illumination can be expanded. have.

In addition, by forming the notches 51a and 51b, the light amount of the transmitted illumination light irradiated onto the glass substrate 4 can be increased compared with the first embodiment.

In addition, this invention is not limited to the said 1st and 2nd embodiment, It can change in various ways.

For example, in the first and second embodiments, the present invention has been described for application to a surface inspection apparatus for inspecting the surface of the glass substrate 4 of a flat panel display such as a liquid crystal display. The present invention can also be applied to substrate holders of various manufactures, such as steppers, which are arranged in the production line of the glass substrate 4.

Moreover, the board | substrate suction member 20 can be provided in arbitrary positions in the opening part of the board | substrate holder 1, and you may install in all the holding stands. In addition, the substrate suction member 20 may replace all of the support pins 30 of the substrate holder 1 with the substrate suction member 20.

In addition, since the illumination is possible, the lower surface opening of the substrate holder 1 may be closed by a transparent holding body (for example, a glass plate), and the substrate sucking member 20 may be disposed on the transparent holding body.

As shown in Fig. 9, the substrate sucking member 20 is provided by screwing the substrate holding shaft 61 to the substrate sucking member main body 60, and moving the substrate holding shaft 61b up and down while rotating. You may make it adjustable. A screw groove 62 is provided on the inner surface of the substrate suction member main body 60a, and a thread 63 is formed at the front end of the substrate holding shaft 61. An O-ring 64 for preventing suction leakage is provided between the substrate suction member main body 60 and the substrate holding shaft 61. The suction passage 23 communicates with the suction tube 21 through the space portion 65 of the substrate suction member main body 60.

The height adjustment of the substrate suction member 20 is moved up and down while the substrate holding shaft 61 rotates, and the suction member 24 at the tip of the substrate holding shaft 61 abuts the reference plane 44. After that, the fixing screw 66 is tightened to fix the substrate holding shaft 61.

The present invention is used for surface defect inspection of semiconductor glass substrates such as glass substrates used for flat panel displays (FPD) such as liquid crystal displays and organic EL displays.

Claims (14)

In the substrate holding apparatus for holding the circumferential edge of the rectangular glass substrate in the opening of the substrate holder formed in a rectangular frame shape and holding it horizontally, A plurality of ladder-shaped holding bodies which are constructed at predetermined intervals at positions lower than the substrate placing surface on which the glass substrate is placed in the opening of the substrate holder, have a long width dimension with respect to the plate thickness, and are made of a highly rigid metal; Wow, A plurality of bearing portions disposed on each of the holding bodies, each having a screw hole; A holding shaft for screwing into the screw hole of each bearing portion, the holding shaft for holding the glass substrate at a distal end portion; And a height adjusting mechanism for vertically moving the holding shaft by screwing the holding shaft to the screw hole of each bearing portion to adjust the height of the holding shaft and to support the glass substrate horizontally. The method of claim 1, The holding shaft is formed in a cylindrical shape, has a freely rotatable ball for supporting the glass substrate at the tip portion, the screw is formed at the bottom, and constitutes a support pin for supporting the glass substrate together with the bearing portion, Or a tubular shape having a screw in the distal end of the bearing portion side, and having a suction member for suction holding and holding the back surface of the glass substrate at the tip portion, and a suction passage communicating with the suction member in the axial direction, wherein Together with the bearing part constitutes the substrate suction member, At least one of the support pin or the substrate suction member is attached to the holding body. The method of claim 1, The holding body has two holding plates made of a highly rigid metal formed in a band shape so as to face the plate surface thereof, A flat portion is formed below the bearing portion, And the planar portion formed on the bearing portion is attached between the two holding plates and is detachably installed. The method of claim 3, wherein And an optical member for scattering or diffusing the transmitted illumination light so that the transmitted illumination light is irradiated from the back side of the glass substrate held in the opening of the substrate holder through the space portion between the two holding plates. Substrate holding device. The method of claim 4, wherein The optical member is a substrate holding apparatus, characterized in that the lens is formed by dividing the lens formed in a cylindrical shape of the light-transmissive resin in the longitudinal direction. The method of claim 1, A substrate holding apparatus characterized by coating a vibration absorbing paint on the surface of the ladder-shaped holding body or by inserting a dustproof material into a space portion of the holding body to suppress vibration of the holding body. The method of claim 1, The plurality of ladder-shaped holding bodies hypothesized at predetermined intervals within the opening of the substrate holder may vary the resonant frequency of each of the holding bodies so that the holding bodies do not resonate by varying the thickness or the mass of the ladder. Substrate holding device. The method of claim 1, The plurality of ladder-shaped holding bodies hypothesized at predetermined intervals in the opening of the substrate holder change the thickness or mass of the dustproof material disposed in the space portion of the holding body so that the holding bodies do not resonate with each other. Substrate holding device, characterized in that to change the resonant frequency of the sieve. delete delete delete delete delete delete

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