JP4951271B2 - Board inspection equipment - Google Patents

Description

  The present invention relates to a substrate inspection apparatus that inspects a substrate using transmitted illumination.

  In a manufacturing process of a flat panel display such as a liquid crystal display, a substrate inspection apparatus that inspects the appearance on a glass substrate to check for defects or the like is used. Some substrate inspection apparatuses have a levitation stage that conveys the glass substrate in a state of being levitated with air so as not to damage the glass substrate. In order to transmit and illuminate the glass substrate, the levitation stage is provided with a gap penetrating in the vertical direction so as to be orthogonal to the conveyance direction of the glass substrate. The substrate inspection apparatus irradiates the glass substrate with illumination light from below through the gap to illuminate the glass substrate, and observes the glass substrate using a microscope disposed above the glass substrate.

  Here, while the glass substrate passes over the gap provided in the levitation stage, the buoyancy due to the blowing of air is reduced, so that the glass substrate is bent and problems such as defocusing of the microscope occur. In addition, when the tip of the glass substrate that has been transported on the levitation stage passes over the gap, the buoyancy is reduced by this gap, so the tip of the glass substrate is caught on the edge of the gap, making it difficult to transport the glass substrate. become. If the width of the gap is narrowed to eliminate such problems, the transmitted illumination light source cannot be arranged in the gap, the transmitted illumination light source is far from the glass substrate, and if the gap width is narrowed, the illumination passes through the gap. Since the amount of light is reduced, the numerical aperture of the illumination light is reduced and the observation image becomes dark.

Therefore, in the conventional substrate inspection apparatus, an air bearing is provided in the gap, and air is blown and sucked simultaneously by the air bearing to the glass substrate passing above the gap, so that the glass substrate in the gap is It is maintained with high accuracy so as to be a predetermined height (for example, see Patent Document 1).
JP 2002-181714 A

However, if an air bearing is provided in the gap as in the conventional substrate inspection apparatus, a compressor for ejecting air and a vacuum pump for sucking air are required separately from the floating stage, so that the structure of the apparatus becomes complicated. There is a problem. Even if an air bearing is provided, a gap through which the transmitted illumination light passes is necessary. However, if the width of the gap in which the transmitted illumination light source is disposed is increased, the same problem as described above occurs. A part of the illumination light may be lost, resulting in a shortage of light.
The present invention has been made in view of such circumstances, and its main purpose is to prevent the deformation of the substrate passing through the gap of the floating stage and to accurately inspect the substrate with a simple structure. It is to provide a substrate inspection apparatus that can be performed well.

The substrate inspection apparatus of the present invention includes a levitation stage for levitating a substrate with air, an observation means for observing the substrate conveyed on the levitation stage in a levitated state, and a lower surface with respect to the levitated substrate. A transmissive illumination light source that irradiates illumination light, an illumination light passage portion that includes a gap that passes vertically through the levitation stage and through which the illumination light can pass, and the illumination light that is fitted so as to close the gap between the illumination light passage portion A transmissive member that transmits light, and is provided on at least one of the levitation stage and the transmissive member, and the upper surface of the transmissive member is substantially the same height as the upper surface of the levitation stage or lower than the upper surface of the levitation stage And an attachment portion for attaching the transmission member to the levitation stage.

  The substrate inspection apparatus of the present invention conveys a substrate by a levitation stage and observes the substrate while irradiating the substrate with illumination light. In order to transmit illumination light, a transmission member is inserted so as to cover at least a part of the gap formed in the floating stage. Thereby, the air ejected from the levitation stage enters between the transmissive member and the substrate to form an air layer, and the air layer maintains the state where the substrate is levitated also in the illumination light passage part.

  According to the substrate inspection apparatus of the present invention, since the transmissive member is inserted into the illumination light passage portion, an air layer is formed between the transmissive member and the substrate by the air ejected from the levitation stage, and illumination is performed by this air layer. The substrate can be levitated also in the light passage portion. Therefore, the height of the substrate in the illumination light passage portion can be kept substantially constant, and the inspection of the substrate by the observation means can be performed with high accuracy.

The best mode for carrying out the present invention will be described in detail with reference to the drawings.
(First embodiment)
As shown in FIG. 1, the substrate inspection apparatus 1 has a base portion 2. Above the base portion 2, a floating stage 3 and a transport unit 4 that transports the glass substrate W along the floating stage 3 are arranged. Has been. In FIG. 1, the conveyance part 4 is laid on the upper surface of the base part 2, and is provided in the guide rail 33 extended in a X direction so that a movement is possible. The transport unit 4 is provided with a plurality of suction pads 35 that come into contact with the outer edge of the glass substrate W from below and suck and hold them. The transport unit 4 sucks and holds the outer edge of the glass substrate W that has floated on the levitation stage 3 by the suction pad 35, and transports the glass substrate W from one end on the near side of the levitation stage 3 to the other end. It is forcibly transported (hereinafter referred to as X direction). Furthermore, the inspection part 5 is fixed to the base part 2 from one end part to the other end part along the X direction. The inspection unit 5 is arranged in the Y direction perpendicular to the X direction and spans the levitation stage 3 and the transport unit 4, and a microscope (observation) provided movably on the beam portion 6A of the portal frame 6. Means) 7 and a transmitted illumination light source 8 which is provided below the microscope 7 and moves in conjunction with the microscope 7. In FIG. 1, the transmitted illumination light source 8 is located outside the floating stage 3, but moves below the optical axis facing the objective lens of the microscope 7 during inspection.

  A plurality of recesses 10 parallel to the X direction are formed in the levitation stage 3 in parallel. A large number of holes 11 for ejecting air are formed at equal intervals on the upper surface 3A of the levitation stage 3 excluding the recess 10. A space is formed for each strip under the numerous holes 11, and the space is connected to an air compressor (not shown). Furthermore, an illumination light passage portion 15 that is a gap for allowing illumination light from the transmitted illumination light source 8 to pass therethrough is formed on the way from the one end side to the other end side of the levitation stage 3. The illumination light passage portion 15 is formed so as to penetrate the levitation stage 3 vertically in parallel with the Y direction. As shown in FIG. 2, a support portion 16 protrudes from the side portion 12 of the levitation stage 3 that faces the illumination light passage portion 15.

A scattering plate 20, which is a transmission member that transmits illumination light, is fitted into the illumination light passage portion 15 from above, and the scattering plate 20 is fixed to the floating stage 3 by a fixing member 21. The scattering plate 20 transmits the illumination light from the transmitted illumination light source 8 while being scattered, and is manufactured from ground glass, a white acrylic plate, or the like, for example. The width in the X direction of the scattering plate 20 is substantially equal to the width in the X direction of the illumination light passage portion 15 formed on the floating stage 3, and the length in the Y direction of the scattering plate 20 is the length in the Y direction of the floating stage 3. Is almost equal to Therefore, the scattering plate 20 is fitted to the side portion 12 of each levitation stage 3 arranged on the downstream side and the upstream side, and the edge portion along the Y direction of the scattering plate 20 is placed on the support portion 16. The upper surface of the scattering plate 20 is substantially flush with the upper surface of each levitation stage 3. The scattering plate 20 is fixed to a predetermined position of the levitation stage 3 by a fixing member 21 (fixing means).
If the illumination light is made uniform by providing the transmission illumination light source 8 with a member that scatters and transmits light, the scattering plate 20 is not provided, and instead, it is made of a transparent material such as glass or plastic. A transparent member may be used.

  As shown in FIG. 3, the fixing member 21 is connected to the outer edge portion of the lower surface by adhesion or the like so as not to block the transmitted illumination light. The interval between the fixing members 21 is adjusted to the interval between the recesses 10. The fixing member 21 has a shape that can be inserted into the width of the concave portion 10 of the levitation stage 3, and the height thereof is lower than the upper surface 3 </ b> A of the levitation stage 3 from the bottom surface of the concave portion 10. As shown in FIG. 2, the fixing member 21 is provided with an insertion hole 23 into which the fastening member 22 is inserted. Further, three height adjusting screw holes 24 are formed so as to surround the insertion hole 23. The adjusting screw hole 24 and the height adjusting screw 25 screwed into the adjusting screw hole 24 constitute adjusting means for adjusting the height and the level of the scattering plate 20.

  As shown in FIG. 4, when the scattering plate 20 is fixed to the levitation stage 3, the scattering plate 20 is fitted into the illumination light passage 15 from above the levitation stage 3, and the fixing member 21 is fitted into the recess 10. In this state, a height adjusting screw 25 made of a headless screw is screwed into the height adjusting screw hole 24. Then, by changing the pushing amount of the height adjusting screw 25, the upper surface of the scattering plate 20 is lower than the upper surface 3A of the levitation stage 3 and parallel to the upper surface 3A, and from the upper surface 3A of the levitation stage 3 to the scattering plate 20 The height difference is adjusted to 1 mm or less. Desirably, the glass substrate W is adjusted to be substantially flush with the upper surface 3A so that the glass substrate W can pass through without difficulty. When the scattering plate 20 is higher than the upper surface 3A, there is a possibility of interference with the glass substrate W. When the height difference from the upper surface 3A of the levitation stage 3 to the scattering plate 20 is larger than 1 mm, the glass substrate W is levitated. This is because it becomes difficult to form a sufficient air layer. When the height of the scattering plate 20 is adjusted, the fastening member 22 is inserted into the insertion hole 23 of the fixing member 21 while maintaining its position, and the fastening member 22 is screwed into the screw hole 13 formed in the concave portion 10 of the levitation stage 3. The scattering plate 20 is fixed to the floating stage 3 by entering. For the fastening member 22 and the height adjusting screw 25, a member whose top is lower than the upper surface 3 </ b> A of the levitation stage 3 is used so as not to protrude from the upper surface 3 </ b> A of the levitation stage 3.

  The transmitted illumination light source 8 disposed below the scattering plate 20 is movably attached to a guide rail 31 laid parallel to the Y direction. The microscope 7 disposed above the scattering plate 20 is movably attached to a guide rail 32 laid in parallel to the Y direction on the beam portion 6A of the portal frame 6. The position of the objective lens of the microscope 7 and the transmitted illumination light source 8 are controlled by a control device (not shown) so that their optical axes always coincide.

  The inspection target of the substrate inspection apparatus 1 may be any substrate that can be observed by transmitted illumination, and the material thereof is not limited to glass but may be plastic or the like. Further, the shape of the inspection object may be a film shape or the like in addition to the plate shape.

Next, the operation of this embodiment will be described.
First, in a state where the transfer unit 4 is in a standby state on one end side (substrate loading area) of the levitation stage 3, the ejection of air is started from the hole 11 of the levitation stage 3. When the glass substrate W is carried onto the levitation stage 3 by a robot, another levitation stage (not shown) or the like, the glass substrate W is floated by an air layer between the levitation stage 3 and positioned (not shown). Aligned to the reference position by the mechanism. In this state, when the suction pad 35 is raised and brought into contact with the glass substrate W to start vacuum suction, the glass substrate W is held by the transport unit 4. And if the conveyance part 4 is moved toward the other end part along the guide rail 32 by drive means, such as a linear motor which is not shown in figure, the glass substrate W will be conveyed on the floating stage 3 in the state which floated with air. .

  When the end of the glass substrate W reaches the illumination light passage 15, air blown from the levitation stage 3 enters between the glass substrate W and the scattering plate 20 to form an air layer. In the conventional substrate inspection apparatus, air escapes from the illumination light passage part, and buoyancy cannot be generated. However, since an air layer is formed between the scattering plate 20 and the glass substrate W, the buoyancy acting on the glass substrate W is maintained also in the illumination light passage portion 15, so that the glass substrate W has a height. The light passes above the illumination light passage 15 while being kept substantially constant. Further, since the upper surface of the fixing member 21 is configured to be substantially flush with the upper surface 3A of the levitation stage 3 or slightly lower than the upper surface 3A, the fixing member 21 blocks the end opening of the recess 10. Air is prevented from escaping to the illumination light passage portion 15. Thereby, a part of the air ejected from each hole 11 of the levitation stage 3 flows into the upper surfaces of the scattering plate 20 and the fixing member 21, and the glass layer W is formed by the air layer between the scattering plate 20 and the glass substrate W. Floats to a certain height from the upper surface of the scattering plate 20. Here, when the microscope 7 and the transmitted illumination light source 8 are moved synchronously, the spot illumination light from the transmitted illumination light source 8 is guided to the illumination light passage unit 15 and scattered by the scattering plate 20 to become scattered light. The glass substrate W is illuminated uniformly from below. The microscope 7 takes an enlarged image of the surface of the glass substrate W illuminated with scattered light from a CCD (Charged Coupled Device) and displays it on a monitor (not shown) connected to the CCD. When there is a defect such as a foreign substance on the glass substrate W, such a foreign substance is found by the enlarged image, and necessary measures are taken. When the inspection unit 5 finishes inspecting the observation target on the glass substrate W, the transport unit 4 is returned to the one end side, and then the vacuum suction is released. The glass substrate W which has been released from the vacuum suction is unloaded from the substrate inspection apparatus 1 by a robot and sent to the next process.

  According to this embodiment, the gap formed in the levitating stage 3 as the illumination light passage part 15 that transmits the transmitted illumination light is closed with the transparent or translucent plate material that transmits the illumination light. Since the air ejected from the levitation stage 3 flows between the scattering plate 20 and an air layer is formed, the glass substrate W is maintained at a constant height on the illumination light passage portion 15 by this air layer. . Thereby, while preventing the deformation | transformation etc. of the glass substrate W, the glass substrate W can be kept at substantially constant height. Accordingly, it is possible to accurately inspect the glass substrate W. Here, since the position of the scattering plate 20 can be accurately adjusted with respect to the levitation stage 3 by the fixing member 21, the glass substrate W and the scattering plate 20 do not contact each other. Further, the height of the scattering plate 20 is adjusted, and the scattering plate 20 is fitted in the upper part of the illumination light passage portion 15 so that there is no gap, so that air leakage is prevented and necessary for the floating of the glass substrate W. An air layer can be reliably formed.

  Further, in the conventional substrate inspection apparatus, since the scattering plate is disposed near the transmitted illumination light source and the scattered light is formed at a position away from the glass substrate W, the field of view is dark. Since the scattering plate 20 is disposed in the vicinity of the glass substrate W, the glass substrate W can be illuminated brightly and without unevenness.

  In addition, as shown in FIG. 5, you may attach the air blow unit 42 to the side part of the microscope 7 which has CCD40. The air blow unit 42 is connected to an air compressor (not shown) or the like, and ejects air downward. If the air blow unit 42 is driven and air is blown toward the upper surface of the scattering plate 20 before the inspection of the glass substrate W is started, the dust accumulated on the scattering plate 20 is blown away without damaging the surface of the scattering plate 20. It is possible to reduce the pseudo defects generated on the scattering plate 20 below the glass substrate W, and to increase the inspection accuracy. Furthermore, the timing at which the air blowing unit 42 performs air blowing on the scattering plate 20 may be after the inspection is completed. At any timing, it is preferable that air blow is performed periodically. Further, the air blow unit 42 determines that the defect of the glass substrate W detected by the microscope 7 is a pseudo defect deposited on the glass substrate W by adjusting the air blow injection direction to the focal position of the objective lens of the microscope 7. In such a case, the air blow unit 42 can be driven to remove the pseudo defects.

(Second Embodiment)
The second embodiment of the present invention is different from the first embodiment only in the method of fixing the scattering plate. Therefore, the description which overlaps with 1st Embodiment is abbreviate | omitted.
As shown in FIG. 6, the fixing member 51 (fixing means) that holds the scattering plate 20 is fixed to the outer edge of the back surface of the scattering plate 20 in accordance with the interval between the concave portions 10 of the levitation stage 3. The outer shape of the fixing member 51 is the same as that of the fixing member 21 of the first embodiment.

  When fixing the scattering plate 20, a washer 52 is laid in the concave portion 10 of the levitation stage 3, and the fixing member 51 is inserted in a state close to fitting from above. The washer 52 is formed with a notch 52A so as to avoid interference with the fastening member 22. A plurality of types of washers 52 having the same shape and different thicknesses are prepared. When the scattering plate 20 is fixed, the prepared plural types of washers 52 are replaced one by one, and the upper surface of the scattering plate 20 is lower than the upper surface 3A of the levitation stage 3 and parallel to the upper surface 3A. The height difference from the upper surface 3A to the scattering plate 20 is adjusted to be 1 mm or less. Desirably, the glass substrate W is adjusted to be substantially flush with the upper surface 3A so that the glass substrate W can pass through without difficulty.

  According to this embodiment, it becomes possible to block the gap of the illumination light passage part 15 by the scattering plate 20, and the same effect as the first embodiment can be obtained. Further, the height of the scattering plate 20 can be adjusted by simply replacing the washer 52.

(Third embodiment)
The third embodiment of the present invention is different from the first and second embodiments only in the method of fixing the scattering plate. Therefore, the description which overlaps with 1st, 2nd embodiment is abbreviate | omitted.
As shown in FIG. 7, in this embodiment, fixing means for fixing the scattering plate 20 by air adsorption is provided on the floating stage 3 side. That is, a plurality of holes 61 penetrating vertically are formed in the support portion 16 of the levitation stage 3. Each hole 61 is connected to each joint 62 fixed below the support portion 16, and each joint 62 is connected via a pipe 63. The pipe 63 is connected to a vacuum pump (not shown). In addition, a washer 64 that also serves as an adsorbing portion that is an adjusting means is disposed at the peripheral edge of the upper opening of the hole 61. A through hole communicating with the hole 61 is formed in the center of the washer 64. As in the second embodiment, a plurality of washers 64 having different thicknesses are prepared. The washer 64 is made of, for example, an elastic resin such as silicone so as not to damage the scattering plate 20. When the scattering plate 20 is fixed, the prepared plural types of washers 64 are replaced one by one, and the upper surface of the scattering plate 20 is lower than the upper surface 3A of the levitation stage 3 and parallel to the upper surface 3A. When the height difference from the upper surface 3A to the scattering plate 20 becomes 1 mm or less, vacuum suction is performed through the hole 61. Desirably, vacuum suction is performed when the glass substrate W is substantially flush with the upper surface 3A so that the glass substrate W can pass through without difficulty.

  According to this embodiment, the scattering plate 20 is vacuum-sucked on the support portion 16 via the hole 61, so that the gap between the illumination light passage portions 15 can be closed. The first embodiment The same effect can be obtained. In addition, since the scattering plate 20 is fixed by vacuum suction, when the height adjustment is necessary, the washer 64 can be easily replaced by simply stopping the vacuum suction. Therefore, it is not necessary to attach or detach the fixing member 51 with screws, and the adjustment work can be performed in a shorter time.

The present invention can be widely applied without being limited to the above embodiments.
For example, the illumination light passage portion 15 may be covered with a transparent glass plate, and the scattering plate may be fixed to the transmitted illumination light source 8. In this case, since an air layer is formed between the glass substrate W and the glass plate in the illumination light passage part 15, the height of the glass substrate W can be kept substantially constant. And since it is a glass plate, there is no attenuation of transmitted illumination light and the glass substrate W can be illuminated brightly. Thus, even when the gap formed as the illumination light passage 15 is closed by the glass plate, an air layer is formed between the upper surface 3A of the levitation stage 3 and the glass substrate W. The height of the glass substrate W can be kept substantially constant.

  Further, as shown in FIG. 8, a transmission illumination light source 70 may be used. The transmitted illumination light source 70 includes a case 71, a line illumination light source 72 in which fluorescent lamps and LEDs are linearly arranged, and a scattering plate 73. The width of the case 71 is substantially equal to the width of the illumination light passage portion 15 in the X direction, and the length of the case 71 is substantially equal to the length of the floating stage in the Y direction. The line illumination light source 72 extends in the Y direction and is accommodated in the case 71. The scattering plate 73 is a transmission member that transmits the line illumination light from the line illumination light source 72 while being scattered, and is fixed so as to cover the upper surface of the case 71. The transmitted illumination light source 70 is attached to the base portion 2 via the lifting mechanism 74. The elevating mechanism 74 is composed of, for example, an air driven cylinder, and once the height is adjusted, the position is held. In the transmitted illumination light source 70, the upper surface of the scattering plate 73 is lower than the upper surface 3A of the levitation stage 3 and parallel to the upper surface 3A, and the height difference from the upper surface 3A of the levitation stage 3 to the scattering plate 20 is 1 mm or less. Positioned. The line illumination light source 72 is arranged on the movement locus of the objective lens of the microscope 7, and only the microscope 7 (see FIG. 1) moves in the Y direction at the time of inspection and performs inspection. According to such a configuration, the same effect as in the first embodiment can be obtained. Instead of the scattering plate 20, a transmissive liquid crystal scattering plate that can be switched to a transparent state or a scattering state may be used.

The glass substrate W may be irradiated with line illumination light by inserting a rod lens into the illumination light passage 15 and causing illumination light from a light source to enter the bottom surface of the rod lens. The rod lens has a slit-shaped exit / transmission port formed on the upper surface facing the optical axis of the microscope 7, and the lens totally reflects incident illumination light. By setting the gap of the illumination light passage portion 15 to be substantially the same size as the diameter and fitting this rod lens into the gap of the illumination light passage portion 15, it becomes possible to reduce the gap of the illumination light passage portion 15, The buoyancy acting on the glass substrate W can be increased. Even with such a configuration, the same effect as the first embodiment can be obtained.
Furthermore, if the drilling interval of the holes 11 and the width of the illumination light passage portion 15 in the X direction are set so that the holes 11 of the levitation stage 3 are arranged at equal intervals in the X direction, the scattering plate 20 can be eliminated. Also, the height of the glass substrate W can be kept substantially constant.

It is a figure which shows the structure of the board | substrate inspection apparatus which concerns on embodiment of this invention. It is the figure which expanded the vicinity of the illumination light transmission part of a levitation | floating stage, Comprising: It is an exploded view explaining fixation of the scattering plate with a height adjustment screw. It is the perspective view which looked at the scattering plate from the lower part. It is a figure which shows the state which inserted the scattering plate in the illumination light transmission part. It is a figure which shows the microscope which provided the air blow unit. It is an exploded view explaining fixation of the scattering plate by a washer. It is an exploded view explaining fixation of the scattering plate by a washer and vacuum suction. It is a figure which shows the case where a permeation | transmission illumination light source is provided in the illuminating light transmission part integrally with a scattering plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate inspection apparatus, 3 ... Levitation stage, 3A ... Upper surface, 7 ... Microscope (observation means), 8 ... Transmission illumination light source, 15 ... Illumination light passage part, 20 ... Scattering plate (transmission member), 21, 51 ... Holding Fixing member (holding and fixing means), 24 ... Screw hole for adjusting height (adjusting means), 42 ... Air blow unit, 52, 64 ... Washer (adjusting means), 61 ... Hole (holding and fixing means), 62 ... Joint (holding) Fixing means), 63 ... piping (holding fixing means), W ... glass substrate (substrate)

Claims (10)

A levitation stage that levitates the substrate with air;
Observation means for observing the substrate conveyed on the levitation stage in a floating state ;
A transmitted illumination light source that irradiates illumination light from the lower surface to the floating substrate;
An illumination light passage part that vertically penetrates the levitation stage and includes a gap through which the illumination light can pass;
A transmission member that is fitted so as to close a gap between the illumination light passage portions and transmits the illumination light ;
The transmissive member is provided on at least one of the levitation stage and the transmissive member, and the transmissive member is positioned so that the upper surface of the transmissive member is substantially the same height as the upper surface of the levitation stage or lower than the upper surface of the levitation stage. An attachment for attaching to the levitation stage;
Substrate inspection device, characterized in that it comprises a.   The substrate inspection apparatus according to claim 1, wherein the transmission member is made of a transparent glass plate that transmits the illumination light.   The substrate inspection apparatus according to claim 1, wherein the transmission member is a scattering plate that scatters the illumination light.   The substrate inspection apparatus according to claim 1, wherein the transmissive member includes a transmissive liquid crystal scattering plate that can be switched to a scattering state that scatters the illumination light or a transmissive state that transmits the illumination light.   5. The substrate inspection apparatus according to claim 1, wherein the attachment portion includes a support portion protruding from a side portion of the levitation stage in the gap.   The mounting portion includes concave portions formed in a plurality of strips on the levitation stage so as to be parallel to the transport direction, and fixing members provided at a plurality of locations along an edge of the transmission member, The board | substrate inspection apparatus as described in any one of Claim 1 to 5 with which the said permeation | transmission member is fixed to the said levitation | floating stage by inserting a member in the said recessed part. Said mounting portion includes a fixing member for fixing the floating stage, provided in the fixing member, any one of claims 1 to 4, further comprising an adjusting means for adjusting the height of the transmitting member with respect to the floating stage The substrate inspection apparatus according to one item. The fixing member includes a screw hole for fixing the substrate formed in the levitation stage, and a fastening member fastened to the screw hole, and the adjusting means adjusts the height of the substrate formed in the fixing member. A height adjusting screw hole to be adjusted; and a height adjusting screw screwed into the screw hole, and changing the amount of pushing the height adjusting screw into the screw hole to change the transmission to the floating stage. The substrate inspection according to claim 7 , wherein the transmitting member is fixed to the levitation stage via the fixing member by adjusting a height of the member and fastening the fastening member to the screw hole for fixing the substrate. apparatus. The mounting portion has a plurality of recesses formed on the levitation stage so as to be parallel to the transport direction, and the fixing member is provided at a plurality of locations along an edge of the transmission member, The board inspection apparatus according to claim 7 , wherein the transmission member is fixed to the levitation stage by fitting the fixing member into the recess.   The substrate inspection apparatus according to claim 1, wherein the observation unit includes an air blow unit that blows air toward the transmission member.

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