TW201412623A - Glass substrate conveyance device and glass substrate manufacturing method - Google Patents

Abstract

To provide a glass substrate conveyance device that suppresses the generation of defect in a glass substrate by having the glass substrate stably levitated for conveyance and a glass substrate manufacturing method. A glass substrate conveyance device 100 comprises a substrate levitation unit 20 and a substrate conveyance unit 30. The substrate levitation unit 20 comprises a plurality of levitation panels 22 that are arranged in a spaced manner in the conveyance direction D1. The levitation panels 22 each comprise a gas ejection mechanism 22a and a substrate-opposing surface 22b. The gas ejection mechanism 22a ejects a gas blowing toward the surface of a glass substrate 10. The substrate-opposing surface 22b is a surface that opposes the surface of the conveyed glass substrate 10 to which the gas blows. The levitation panels 22 are arranged in such a way that the height-wise position of the substrate-opposing surface 22b is gradually lowered along with the conveyance direction D1.

Description

Glass substrate transfer device and method for manufacturing glass substrate

The present invention relates to a glass substrate transfer device and a glass substrate manufacturing method.

In the manufacturing process of a flat panel display (FPD) such as a liquid crystal display device, a pattern including a semiconductor element such as a TFT (Thin Film Transistor) and a black matrix resin is formed on the surface of the glass substrate. When there are defects such as damage, cracks, and foreign matter on the surface of the glass substrate on which the pattern is formed, the pattern is not formed satisfactorily, which is a cause of failure of the FPD as a final product. In particular, minute damage and cracks formed on the surface of the glass substrate cause a decrease in the mechanical strength of the glass substrate, which causes cracking of the glass substrate in the manufacturing process of the FPD. Therefore, it is required that the surface of the glass substrate is free from defects.

In the manufacturing step of the glass substrate, the formed glass piece is cut into a specific size to obtain a glass substrate which is a product shipped in size. Thereafter, the glass substrate is subjected to end surface processing steps, cleaning steps, and inspection steps by grinding and polishing, and is shipped by being bundled. In the inspection step, for example, the glass substrate is conveyed, and defects such as damage, cracks, and foreign matter existing on the surface of the glass substrate are optically detected.

In the inspection step of the glass substrate, a roller conveyor was previously used as a conveying means for the glass substrate. However, if foreign matter such as a small piece of glass adheres to the roll of the roller conveyor, the surface of the glass substrate to be conveyed is damaged by foreign matter due to contact with the rotating roll. In order to solve this problem, in recent years, as in Patent Document 1 (Japanese Patent Laid-Open) In the same manner as disclosed in JP-A-2006-188313, a glass substrate transfer device that blows a gas onto a surface of a glass substrate to float the glass substrate and sucks and holds the end portion of the glass substrate is used. In the method of using the conveying device, the glass substrate is conveyed in a floating state without coming into contact with the conveying device. Therefore, the occurrence of defects on the surface of the glass substrate due to the contact of the glass substrate with the transfer device is suppressed.

However, when the glass substrate is floated and transported, the glass substrate itself may be in contact with the transfer device due to warpage of the glass substrate itself. Further, the warpage of the glass substrate is difficult to completely measure due to the following three reasons. As a first reason, it is actually difficult to measure the free shape of each of the glass substrates produced in large quantities. For the second reason, even if warpage is measured by extracting a glass substrate for inspection from a glass substrate for mass production to predict warpage in a specific production batch, the free shape of the glass substrate is also in a certain range. There is a change within. For the third reason, the measurement of the free shape of a plurality of small glass substrates taken from a large mother glass is particularly difficult.

In order to solve this problem, it is disclosed in the patent document 2 (Japanese Laid-Open Patent Publication No. 2012-96920) that the gas is blown onto the surface of the glass substrate, and the glass substrate is floated while the gas is being sucked, and the glass substrate is applied downward. A transfer device for a glass substrate. In the conveying method using the conveying device, since the shape of the glass substrate conveyed in the floating state is corrected to some extent, the influence of the warpage of the glass substrate is reduced.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-188313

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2012-96920

However, as disclosed in Patent Document 2, the conveying device for the glass substrate includes a plurality of floating panels arranged at a predetermined interval along the conveying direction of the glass substrate. At the time, other problems due to warpage of the glass substrate occur. Specifically, in the region between the floating panels adjacent to the transport direction of the glass substrate, the glass substrate is not subjected to a downward force, and thus the shape of the glass substrate is not corrected. Therefore, in this region, there is a possibility that the glass substrate returns to its original shape and causes warpage of the glass substrate. Therefore, when the glass substrate passes through the region between the floating panels, the end portion of the glass substrate that hangs down due to the warpage contacts the conveying device to rupture the glass substrate.

An object of the present invention is to provide a glass substrate transfer apparatus and a glass substrate production method capable of suppressing the occurrence of defects in a glass substrate by stably floating the glass substrate.

The glass substrate transfer apparatus of the present invention includes a substrate floating unit and a substrate transfer unit. The substrate floating unit is a unit that blows a gas onto the surface of the glass substrate to float the glass substrate. The substrate transfer unit transports the unit of the glass substrate that is floated by the substrate floating unit in the transport direction. The substrate inspection unit inspects the unit of the glass substrate conveyed by the substrate transfer unit. The substrate floating unit includes a plurality of floating panels that are arranged at intervals along the transport direction. The floating panel includes a gas ejection mechanism and a substrate facing surface. The gas ejecting mechanism ejects the gas blown onto the surface of the glass substrate. The opposite surface of the substrate faces the surface on which the gas-coated surface of the glass substrate to be conveyed is blown. The floating panel is disposed such that the height position of the opposing surface of the substrate gradually decreases toward the transport direction.

The glass substrate transfer device of the present invention is a device that transports a glass substrate in a specific transport direction. The substrate floating unit that floats the glass substrate has a configuration in which a plurality of floating panels are arranged at a predetermined interval along the conveying direction of the glass substrate.

In the glass substrate transfer apparatus, the glass substrate that has been lifted and transported is placed above the substrate floating unit, and its shape is corrected to some extent. Therefore, the warpage of the glass substrate is reduced above the floating unit of the substrate. On the other hand, the glass substrate that has been transported up and down is not in the shape of the region between the floating panels adjacent to each other in the transport direction. To the correction, it returns to its own shape. Therefore, there is a possibility that the glass substrate may be warped in the region between the floating panels. However, the floating panel is arranged in a stepped shape such that the height of the opposing surface of the substrate facing the lower surface of the glass substrate to be conveyed gradually decreases along the conveying direction of the glass substrate. Therefore, even when the end portion of the glass substrate passing through the region between the floating panels is sag due to warpage, the end portion of the glass substrate is prevented from coming into contact with the floating panel.

Therefore, the glass substrate transfer apparatus can transport the glass substrate by stably floating it, thereby suppressing the occurrence of defects in the glass substrate.

Further, the opposing surface of the substrate of the floating panel disposed along the transport direction is preferably parallel to the horizontal plane.

Further, it is preferable that the substrate floating unit gradually increases the flow rate of the gas ejected from the gas ejecting mechanism of the floating panel toward the conveying direction.

When the flow rate of the gas ejected from the gas ejecting mechanism of the floating panel is fixed along the conveying direction of the glass substrate, the height position of the glass substrate to be conveyed gradually decreases in accordance with the height position of the opposing surface of the substrate of the floating panel. However, by gradually increasing the flow rate of the gas ejected from the gas ejecting mechanism along the transport direction of the glass substrate, it is possible to suppress a decrease in the height position of the glass substrate to be transported. Thereby, deformation of the glass substrate conveyed by the substrate transfer unit can be suppressed.

Moreover, it is preferable that the glass substrate transfer apparatus of the present invention further includes a substrate inspection unit. The substrate inspection unit inspects the optical device of the glass substrate conveyed by the substrate transfer unit. The floating panel extends in the width direction of the glass substrate in the direction orthogonal to the transport direction. The substrate inspection unit is disposed between adjacent floating panels.

The glass substrate transfer device can detect defects formed on the surface of the glass substrate. In this apparatus, a substrate inspection unit extending in the width direction of the glass substrate can be provided between the floating panels adjacent to each other in the conveyance direction of the glass substrate. Therefore, the installation space of the substrate inspection unit in the conveyance direction of the glass substrate can be suppressed.

The method for producing a glass substrate of the present invention includes a substrate floating step, a substrate transfer step, and a substrate processing step. The substrate floating step is a step of blowing a gas onto the surface of the glass substrate to float the glass substrate. The substrate transfer step is a step of transporting the glass substrate that has been lifted by the substrate floating step in the transport direction. The substrate processing step is a step of processing or inspecting the glass substrate conveyed in the substrate transfer step. In the substrate floating step, the glass substrate is floated by a plurality of floating panels arranged at intervals along the transport direction. The floating panel includes a gas ejection mechanism and a substrate facing surface. The gas ejecting mechanism ejects the gas blown onto the surface of the glass substrate. The opposite surface of the substrate faces the surface on which the gas-coated surface of the glass substrate to be conveyed is blown. The floating panel is disposed such that the height position of the opposing surface of the substrate gradually decreases toward the transport direction.

Further, the opposing surface of the substrate of the floating panel disposed along the transport direction is preferably parallel to the horizontal plane.

Further, in the method for producing a glass substrate of the present invention, it is preferable that the substrate processing step is a substrate inspection step of inspecting the glass substrate conveyed in the substrate transfer step. In the substrate inspection step, the glass substrate is inspected using an optical device disposed between adjacent floating panels.

In the glass substrate transfer apparatus and the glass substrate manufacturing method of the present invention, the glass substrate is stably floated and transported, whereby the occurrence of defects of the glass substrate can be suppressed.

10‧‧‧ glass substrate

10a‧‧‧lower surface

20‧‧‧Substrate floating unit

22‧‧‧ floating panel

22a‧‧‧ gas ejection mechanism

22b‧‧‧substrate opposite

22c‧‧‧ gas suction mechanism

24‧‧‧Floating panel array

26‧‧‧Slit

30‧‧‧Substrate transport unit

32‧‧‧Substrate retention department

34‧‧‧Substrate transport department

40‧‧‧Substrate inspection unit

40a‧‧‧ camera

40b‧‧‧Light source

100‧‧‧Glass substrate transfer device

120‧‧‧Substrate floating unit

200‧‧‧Glass substrate transfer device

D1‧‧‧Transfer direction

D2‧‧‧width direction

L1‧‧‧ size

L2‧‧‧ size

L3‧‧‧ distance

L4‧‧‧ height difference

S1‧‧‧ steps

S2‧‧‧ steps

S3‧‧‧ steps

S4‧‧‧ steps

S5‧‧ steps

S6‧‧ steps

S7‧‧ steps

S8‧‧‧ steps

Fig. 1 is a flow chart showing the steps of manufacturing the glass substrate of the embodiment.

2 is an external view of a glass substrate transfer device.

Figure 3 is a plan view of the substrate floating unit.

Figure 4 is a side view of the substrate floating unit.

Figure 5 is an enlarged view of a portion of Figure 4.

6 is a plan view showing a substrate floating unit in a configuration of a floating panel as a reference example. Figure.

(1) Outline of manufacturing steps of a glass substrate using a glass substrate transfer device

An embodiment of the transport apparatus for a glass substrate of the present invention will be described with reference to the drawings. First, a manufacturing procedure of the glass substrate 10 used in the glass substrate conveying apparatus 100 used in the present embodiment will be described. The glass substrate 10 is used for the manufacture of a flat panel display (FPD) such as a liquid crystal display, a plasma display, and an organic EL (electroluminescence) display. The glass substrate 10 has a thickness of, for example, 0.2 mm to 0.8 mm, and has a length of 680 mm to 2200 mm and a width of 880 mm to 2500 mm.

An example of the glass substrate 10 is glass having the following composition.

(a) SiO ₂ : 50% by mass to 70% by mass, (b) Al ₂ O ₃ : 10% by mass to 25% by mass, (c) B ₂ O ₃ : 5% by mass to 18% by mass, (d) MgO : 0% by mass to 10% by mass, (e) CaO: 0% by mass to 20% by mass, (f) SrO: 0% by mass to 20% by mass, (g) BaO: 0% by mass to 10% by mass, (h) RO: 5 mass% to 20 mass% (R is at least one selected from the group consisting of Mg, Ca, Sr, and Ba), and (i) R' ₂ O: 0% by mass to 2.0% by mass (R' is selected from At least one of Li, Na, and K) and (j) a metal oxide selected from at least one of SnO ₂ , Fe ₂ O _{3 ,} and CeO ₂ .

Further, the glass having the above composition is allowed to have other trace components in the range of less than 0.1% by mass.

FIG. 1 is a view showing an example of a flow chart of a manufacturing step of the glass substrate 10. The manufacturing steps of the glass substrate 10 mainly include a forming step (step S1), a plate-shaped cutting step (step S2), a cutting step (step S3), a roughening step (step S4), an end surface processing step (step S5), clear The washing step (step S6), the checking step (step S7), and the packing step (step S8).

In the forming step S1, the molten glass obtained by self-heating the glass raw material by a down-draw method or a floating method continuously forms a glass piece. The formed glass piece is controlled to a temperature so as not to be deformed or warped, and is cooled to a temperature below the glass freezing point.

In the plate-like cutting step S2, the formed glass piece in the forming step S1 is cut to obtain a mother glass having a specific size.

In the cutting step S3, the mother glass obtained in the plate-like cutting step S2 is cut to obtain a glass substrate 10 having a product size. In general, the mother glass is cut using a cutter or laser.

In the roughening step S4, the roughening treatment for increasing the surface roughness of the glass substrate 10 obtained in the cutting step S3 is performed. The roughening treatment of the glass substrate 10 is, for example, wet etching using an etchant containing hydrogen fluoride.

In the end surface processing step S5, the end surface processing of the glass substrate 10 subjected to the roughening treatment in the roughening step S4 is performed. The end surface processing is, for example, polishing and grinding of the end surface of the glass substrate 10, and chamfering of the glass substrate 10.

In the cleaning step S6, the glass substrate 10 subjected to the end surface processing in the end surface processing step S5 is cleaned. On the glass substrate 10, a small piece of glass which is cut by the cutting of the mother glass and the end surface of the glass substrate 10, or an organic substance such as an organic substance existing in the environment is adhered. The foreign matter is removed by cleaning the glass substrate 10.

In the inspection step S7, the cleaned glass substrate 10 in the cleaning step S6 is inspected. Specifically, the glass substrate 10 is conveyed to face defects such as damage and cracks on the surface of the glass substrate 10, foreign matter adhering to the surface of the glass substrate 10, and minute bubbles existing inside the glass substrate 10. Optical inspection.

In the packing step S8, the glass substrate 10 which has passed the inspection in the inspection step S7 and the spacer paper for protecting the glass substrate 10 are alternately laminated on the pallet and bundled. The bundled glass substrate is shipped from 10 to the manufacturer of the FPD.

(2) Details of the glass substrate transfer device

Next, the glass substrate transfer apparatus 100 of the present embodiment will be described. FIG. 2 is an external view of the glass substrate transfer device 100. The glass substrate transfer apparatus 100 is for inspecting the defect existing in the surface while carrying the glass substrate 10 in the inspection step S7. The glass substrate transfer apparatus 100 conveys the glass substrate 10 supported in a horizontal state in a specific direction, and optically inspects a defect existing on the surface of the glass substrate 10. The glass substrate transfer apparatus 100 mainly includes a substrate floating unit 20, a substrate transfer unit 30, and a substrate inspection unit 40. The glass substrate transfer apparatus 100 includes a transfer apparatus including a glass substrate of the substrate floating unit 20 and the substrate transfer unit 30. Hereinafter, as shown in FIG. 2, the direction in which the glass substrate 10 in the horizontal state is conveyed is referred to as "transport direction D1", and the direction in the horizontal plane orthogonal to the transport direction of the glass substrate 10 is referred to as "width direction D2". In addition, the end portion of the glass substrate 10 and the end portion parallel to the transport direction D1 is referred to as a "side end portion", and the end portion of the glass substrate 10 and the end portion parallel to the width direction D2 is referred to as "before and after". Ends". In FIG. 2, the glass substrate 10 is conveyed in the direction of the arrow shown by the symbol D1.

(2-1) Substrate floating unit

The substrate floating unit 20 is a unit that blows gas to the lower surface 10a of the glass substrate 10 in a horizontal state to float the glass substrate 10. The substrate floating unit 20 mainly includes a plurality of floating panels 22. 3 is a plan view of the substrate floating unit 20. In Figure 3, the floating panel 22 is represented by a shaded area. 4 is a side view of the substrate floating unit 20. Figure 5 is an enlarged view of a portion of Figure 4. In FIGS. 4 and 5, the size in the vertical direction is exaggerated. The plurality of floating panels 22 are formed by the floating panel array 24 without being spaced apart in the width direction D2. The plurality of floating panel arrays 24 are arranged at a predetermined interval along the transport direction D1. Hereinafter, the space between the two floating panel arrays 24 adjacent to each other in the transport direction D1 is referred to as "slit 26". As shown in FIG. 3, the slit 26 is a space in which the width direction D2 extends.

As shown in FIG. 5, the floating panel 22 includes a gas ejecting mechanism 22a, a substrate opposing surface 22b, and a gas suction mechanism 22c. The substrate facing surface 22b is an upper end surface of the floating panel 22, Further, as shown in FIG. 4, it faces the lower surface 10a of the glass substrate 10 to be conveyed. The substrate opposing faces 22b of the floating panel 22 disposed along the conveying direction D1 are parallel to each other. In the present embodiment, the substrate facing surface 22b is parallel to the horizontal plane, but the substrate facing surface 22b may be slightly inclined along the conveying direction D1. The floating panel 22 is provided such that the substrate facing surface 22b is parallel to the horizontal plane. The substrate facing faces 22b of all the floating panels 22 constituting each of the floating panel arrays 24 have the same height position. That is, in FIG. 3, the substrate opposing faces 22b of the plurality of floating panels 22 which are adjacently disposed in the width direction D2 have the same height position.

The gas discharge mechanism 22a is a mechanism for discharging a gas such as air upward from the substrate facing surface 22b. The gas ejecting mechanism 22a is, for example, a plurality of minute holes formed in the opposing surface 22b of the substrate. The gas ejected upward from the gas ejecting mechanism 22a collides with the lower surface 10a of the glass substrate 10 to be transported. Thereby, the glass substrate 10 to be conveyed receives an upward force. This upward force causes the glass substrate 10 to float from the substrate facing surface 22b of the floating panel 22.

The gas suction mechanism 22c is a mechanism for sucking gas from the space above the substrate opposing surface 22b toward the substrate facing surface 22b. The gas suction mechanism 22c is, for example, a hole formed in the opposing surface 22b of the substrate. The gas is sucked by the gas suction mechanism 22c, and the space in the vicinity of the gas suction mechanism 22c is in a state of a negative pressure between the lower surface 10a of the glass substrate 10 to be conveyed and the substrate facing surface 22b. Thereby, the glass substrate 10 to be conveyed receives a downward force. This downward force corrects the shape of the glass substrate 10 to be conveyed to some extent.

The dimension of the width direction D2 of the floating panel array 24 is longer than the dimension of the width direction D2 of the glass substrate 10. The dimension L1 of the transport direction D1 of the floating panel 22 is, for example, 100 mm to 150 mm. The dimension L2 of the transport direction D1 of the slit 26 is, for example, 25 mm to 30 mm. The distance L3 between the lower surface 10a of the floating glass substrate 10 and the substrate facing surface 22b of the floating panel 22 is, for example, 25 μm to 35 μm.

As shown in FIG. 4, the floating panel array 24 is disposed such that the height position of the substrate facing surface 22b of the floating panel 22 gradually decreases toward the transport direction D1. Specifically, as the direction in which the glass substrate 10 is conveyed is advanced, the height position of the opposite surface 22b of the substrate is 10 The range of μm~20μm decreases. That is, as shown in FIG. 5, the difference L4 between the height positions of the substrate facing surfaces 22b of the floating panel 22 in the two floating panel arrays 24 adjacent to each other in the transport direction D1 is 10 μm to 20 μm.

Further, in the substrate floating unit 20, the flow rate of the gas ejected from the gas ejecting mechanism 22a of the floating panel 22 gradually increases toward the transport direction D1. That is, the lower the height position of the substrate facing surface 22b of the floating panel 22, the larger the flow rate of the gas ejected from the gas ejecting mechanism 22a of the floating panel 22.

(2-2) Substrate transport unit

The substrate transfer unit 30 transports the unit of the glass substrate 10 that has been floated by the substrate floating unit 20 along the transport direction D1. The substrate transfer unit 30 mainly includes a substrate holding portion 32 and a substrate transfer portion 34.

The substrate holding portion 32 holds one end portion of the glass substrate 10 . The substrate holding portion 32 includes, for example, an adsorption mechanism for holding the glass substrate 10. The substrate transport unit 34 includes a linear drive mechanism that moves the substrate holding unit 32 in the transport direction D1.

When the glass substrate 10 is transported by the substrate transport unit 30 in the transport direction D1, the glass substrate 10 alternately passes through the space above the floating panel array 24 and the space above the slit 26.

(2-3) Substrate inspection unit

The substrate inspection unit 40 inspects the unit of the glass substrate 10 conveyed by the substrate transfer unit 30. The substrate inspection unit 40 has an optical function of optically detecting defects such as damage and cracks on the surface of the glass substrate 10, foreign matter adhering to the surface of the glass substrate 10, and minute bubbles existing inside the glass substrate 10. Device.

In the present embodiment, as shown in FIG. 4, the substrate inspection unit 40 includes a plurality of cameras 40a disposed in one slit 26. The camera 40a photographs the surface of the glass substrate 10 passing through it. The substrate inspection unit 40 further includes a light source 40b disposed in a space above the slit 26 provided with the camera 40a. The light source 40b illuminates high-intensity light toward the surface of the glass substrate 10 passing through below. The substrate inspection unit 40 may also have a light source 40b disposed in the slit 26, and the phase The machine 40a is disposed in a space above the slit 26. Further, the amount of change in the height position of the substrate facing surface 22b of the floating panel 22 in the transport direction D1 is set within a range not deviating from the depth of field of the camera 40a.

The plurality of cameras 40a of the substrate inspection unit 40 are disposed in one slit 26 along the width direction D2 so that the entire area D2 of the glass substrate 10 can be inspected. That is, the camera 40a provided in one slit 26 can capture the entire area of the glass substrate 10 in the width direction D2.

The substrate inspection unit 40 further includes a control unit (not shown). The control unit has a computer that detects a function of a defect existing on the surface of the glass substrate 10 to be conveyed. For example, the control unit analyzes an image of the surface of the glass substrate 10 captured by the camera 40a, and detects damage or cracks on the surface of the glass substrate 10 or foreign matter adhering to the surface of the glass substrate 10.

The control unit of the substrate inspection unit 40 is connected to a glass substrate packaging device (not shown) that bundles the glass substrate 10 in the packaging step S8. The control unit has a function of notifying the substrate packing device that the glass substrate 10 having the surface defect is detected. Thereby, in the packing step S8, the glass substrate packing apparatus can prevent the glass substrate 10 which has a surface defect from being bundled.

(3) Features

(3-1)

The glass substrate conveying apparatus 100 of the present embodiment detects the defects formed on the surface of the glass substrate 10 while conveying the glass substrate 10 along the conveying direction D1. The substrate floating unit 20 that floats the glass substrate 10 has a configuration in which a plurality of floating panels 22 are provided at a predetermined interval L2 along the transport direction D1.

The upward force is applied to the glass substrate 10 passing over the floating panel 22 by the gas ejected from the gas ejecting mechanism 22a. Further, a downward force is applied to the glass substrate 10 passing over the floating panel 22 by the gas sucked to the gas suction mechanism 22c. The upward force is the force for floating the glass substrate 10, and the downward force is to correct the glass substrate 10 to some extent. The power of the shape. The glass substrate 10 has a specific shape, and for example, a concave portion and a convex portion are formed on the surface of the glass substrate 10. By correcting the force of the shape of the glass substrate 10, the surface of the glass substrate 10 is in a state in which the concave portion and the convex portion are not formed.

However, between the adjacent floating panel arrays 24 in the transport direction D1, there is a slit 26 in which the camera 40a of the substrate inspection unit 40 is provided. Therefore, the glass substrate 10 conveyed by the substrate transfer unit 30 along the transport direction D1 has a region above the slit 26. In this region, the upward force obtained by the gas discharge mechanism 22a and the downward force obtained by the gas suction mechanism 22c are not applied. Therefore, the region of the glass substrate 10 passing over the slit 26 is restored to its original shape.

In particular, during the period in which the rear end portion of the glass substrate 10 passes over the slit 26, the front end portion of the glass substrate 10 may sag due to the inherent warpage of the glass substrate 10. However, in the present embodiment, the floating panel 22 constituting the floating panel array 24 is arranged in a stepped manner such that the height position of the substrate facing surface 22b gradually decreases in the transport direction D1. Therefore, even when the rear end portion of the glass substrate 10 above the slit 26 is sagged due to warpage, the front end portion of the glass substrate 10 and the substrate facing surface 22b of the floating panel 22 can be sufficiently ensured. interval.

In addition, when the thickness of the glass substrate 10 is 0.5 mm, the specific gravity of the glass substrate 10 is 2.19 g/cm ³ , and the Young's modulus of the glass substrate 10 is 70,000 N/mm ² , and the front end of the glass substrate 10 is used When the dimension of the transport direction D1 of the section is 30 mm, the theoretical value of the amount of deflection of the rear end portion of the glass substrate 10 downward is 1.49 μm. In the present embodiment, since the dimension L2 of the transport direction D1 of the slit 26 is 30 mm, it is predicted that the amount of deflection caused by the self weight of the glass substrate 10 is less than 2 μm. Moreover, the difference L4 between the height positions of the substrate facing surfaces 22b of the adjacent floating panel 22 in the transport direction D1 is 10 μm to 20 μm. Therefore, when the front end portion of the glass substrate 10 above the slit 26 is bent downward due to its own weight, the front end portion of the glass substrate 10 and the substrate of the floating panel 22 located before the transport direction D1 are also suppressed. The opposite surface 22b is in contact.

According to the above, the substrate floating unit 20 of the present embodiment can prevent the rear end portion of the glass substrate 10 passing over the slit 26 from coming into contact with the floating panel 22. If the front end portion of the glass substrate 10 is in contact with the floating panel 22, there is a possibility that the glass substrate 10 is broken. Therefore, the glass substrate transfer apparatus 100 can suppress the occurrence of defects of the glass substrate 10.

(3-2)

In recent years, the commercially available floating panel 22 is provided with a substrate facing surface 22b having a high degree of flatness. Moreover, the uncertainties related to the levelness of the floating panel 22 and the substrate floating unit 20 as a whole can be measured and adjusted by the processing precision of each component constituting the substrate floating unit 20 and the position of the substrate floating unit 20. And roughly removed. However, the uncertain elements related to the inherent shape of the glass substrate 10 are difficult to completely remove. In particular, it is difficult to completely measure the warpage of the glass substrate 10 that is continuously conveyed.

In the substrate floating unit 20 of the present embodiment, even when the warpage of the glass substrate 10 cannot be completely measured, the front end portion of the glass substrate 10 can be prevented from coming into contact with the floating panel 22. Therefore, the glass substrate transfer apparatus 100 can suppress the occurrence of defects of the glass substrate 10.

(3-3)

In the glass substrate transfer apparatus 100 of the present embodiment, the flow rate of the gas ejected from the gas ejecting mechanism 22a of the floating panel 22 gradually increases toward the transport direction D1.

When the flow rate of the gas ejected from the gas ejecting mechanism 22a of the floating panel 22 is fixed along the transport direction D1 of the glass substrate 10, the height position of the glass substrate 10 to be transported and the substrate facing surface 22b of the floating panel 22. The height position gradually decreases. However, by gradually increasing the flow rate of the gas ejected from the gas ejecting mechanism 22b along the transport direction D1 of the glass substrate 10, the decrease in the height position of the glass substrate 10 to be transported is suppressed. In other words, the amount of change in the height position of the glass substrate 10 to be conveyed is smaller than the amount of change in the height position of the substrate facing surface 22b in the transport direction D1. Thereby, deformation of the conveyed glass substrate 10 due to a change in the height position of the opposing surface 22b of the substrate is suppressed.

Therefore, the glass substrate conveying apparatus 100 of the present embodiment can suppress deformation of the glass substrate 10 conveyed by the substrate conveying unit 30.

(3-4)

In the glass substrate transfer apparatus 100 of the present embodiment, the floating panel array 24 including a plurality of floating panels 22 extends in the width direction D2. Further, the camera 40a of the substrate inspection unit 40 is disposed in the slit 26 between the adjacent floating panel arrays 24 in the transport direction D1.

As a reference example, as shown in FIG. 6, in order to suppress contact between the glass substrate 10 and the floating panel 22 due to warpage of the glass substrate 10, it is conceivable to arrange the floating panel 22 as a lattice-like substrate floating unit 120. Fig. 6 is a plan view of the substrate floating unit. In Figure 6, the floating panel 22 is represented by a shaded area. In the substrate floating unit 120, in order to inspect all the areas in the width direction D2 of the glass substrate 10, it is necessary to arrange the cameras 40a of the substrate inspection unit 40 in a plurality of rows along the transport direction D1. Therefore, there is a problem in that the configuration of the substrate inspection unit 40 is complicated and the entire glass substrate transfer device 200 is enlarged.

In the glass substrate transfer apparatus 100 of the present embodiment, as shown in FIG. 3, the width direction D2 of the glass substrate 10 can be inspected by providing the camera 40a of the substrate inspection unit 40 in a slit 26 along the width direction D2. All areas. Therefore, since the glass substrate transfer apparatus 100 can suppress the installation space of the board|substrate inspection unit 40, the enlargement of the whole glass substrate conveyance apparatus 100 can be suppressed.

(4) Variations

Although the method of manufacturing the glass substrate of the present invention has been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the spirit and scope of the invention. Further, in the present embodiment, an example of the inspection procedure of the glass substrate has been described. However, the glass substrate transfer apparatus of the present invention can also be used in the processing steps of other glass substrates.

(4-1) Change A

In the present embodiment, the substrate floating unit 20 includes a gas suction mechanism 22c that generates a downward force on the glass substrate 10 to be conveyed. However, instead of the gas suction mechanism 22c, another gas discharge mechanism that discharges gas downward may be provided above the substrate floating unit 20. The gas ejected from the gas ejecting mechanism collides with the upper surface of the glass substrate 10 to be transported, thereby imparting a downward force to the glass substrate 10 to be transported. Therefore, in this case, the force of correcting the shape of the glass substrate 10 to some extent is imparted to the glass substrate 10 conveyed by the substrate transfer unit 30.

(4-2) Change B

In the present embodiment, the camera 40a of the substrate inspection unit 40 is disposed in one slit 26 as shown in FIG. 4, but may be disposed in the plurality of slits 26. By providing the camera 40a of the substrate inspection unit 40 in the plurality of slits 26, for example, an optical inspection having a different measurement range can be performed for each slit 26. In this case, the substrate inspection unit 40 can perform optical inspection for detecting damage and cracks formed on the surface of the glass substrate 10 in one slit 26, and detecting the presence of the glass substrate 10 in the other slits 26, for example. Optical inspection of tiny bubbles inside.

Further, in the case of inspecting the glass substrate having the surface to be etched, the substrate inspection unit 40 can perform normal optical inspection in one slit 26, for example, and lower the illuminance and sensitivity in the other slits 26. Optical inspection.

10‧‧‧ glass substrate

10a‧‧‧lower surface

22‧‧‧ floating panel

22a‧‧‧ gas ejection mechanism

22b‧‧‧substrate opposite

22c‧‧‧ gas suction mechanism

24‧‧‧Floating panel array

26‧‧‧Slit

40a‧‧‧ camera

100‧‧‧Glass substrate transfer device

D1‧‧‧Transfer direction

L1‧‧‧ size

L2‧‧‧ size

L3‧‧‧ distance

L4‧‧‧ height difference

Claims (8)

A glass substrate transfer apparatus comprising: a substrate floating unit that blows gas onto a surface of the glass substrate to float the glass substrate; and a substrate transfer unit that transports the floating unit by the substrate floating unit in the transport direction a glass substrate; wherein the substrate floating unit includes a plurality of floating panels arranged at intervals along the transport direction, the floating panel includes a gas discharge mechanism that discharges the gas, and the surface of the glass substrate that is transported The substrate facing surface is disposed such that the height position of the opposite surface of the substrate gradually decreases toward the transport direction. The glass substrate transfer apparatus of claim 1, wherein the substrate facing surface of the floating panel disposed along the transport direction is parallel to a horizontal plane. The glass substrate transfer apparatus according to claim 1 or 2, wherein the substrate floating unit gradually increases a flow rate of the gas ejected from the gas ejecting mechanism of the floating panel toward the transport direction. The glass substrate transfer apparatus according to claim 1 or 2, further comprising: a substrate inspection unit that inspects an optical device of the glass substrate conveyed by the substrate transfer unit, wherein the floating panel is aligned in a direction orthogonal to the conveyance direction That is, the glass substrate extends in the width direction, and the substrate inspection unit is disposed between the adjacent floating panels. The glass substrate transfer device of claim 3, which further comprises the inspection of the substrate a substrate inspection unit that is an optical device of the glass substrate that is transported by the transport unit, and the floating panel extends in a direction orthogonal to the transport direction, that is, in a width direction of the glass substrate, and the substrate inspection unit is disposed adjacent to the floating Between panels. A method for producing a glass substrate, comprising: a substrate floating step of blowing a gas onto a surface of the glass substrate to float the glass substrate; and a substrate transporting step of transporting in the transport direction by the substrate floating step The glass substrate; and the substrate processing step of processing or inspecting the glass substrate conveyed in the substrate transfer step; and disposing at intervals in the transfer direction in the substrate floating step The plurality of floating panels are configured to float the glass substrate, and the floating panel includes a gas ejecting mechanism that ejects the gas and a substrate facing surface opposite to the surface of the glass substrate that is transported, and the height of the opposite surface of the substrate The position is arranged to gradually decrease toward the above-described conveying direction. The method of manufacturing a glass substrate according to claim 6, wherein the substrate facing surface of the floating panel disposed along the transport direction is parallel to a horizontal plane. The method of manufacturing a glass substrate according to claim 6 or 7, wherein the substrate processing step is a substrate inspection step of inspecting the glass substrate conveyed in the substrate transfer step, and is disposed adjacent to the substrate inspection step The glass substrate is inspected by the optical device between the floating panels described above.