JP2018135226A - Glass substrate for display, and production method of glass substrate for display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass substrate for display in which electrostatic charge due to peeling is scarcely generated when peeled off from a suction stage, and to provide a production method of the same.SOLUTION: In a glass substrate for display, when an average value of fluorine concentration (mol%) at a depth of 0 to 10 nm from a glass surface of the glass substrate on the side opposite to the semiconductor element formation surface is indicated by F, and an average value of fluorine concentration (mol%) at a depth of 100 to 400 nm from the glass surface is indicated by F, an inequality (F)/(F)≥3 is satisfied, and surface roughness Ra of the glass surface on the side opposite to the semiconductor element formation surface is 0.3 nm or more.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a glass substrate for display and a method for producing a glass substrate for display.

  In a flat panel display (FPD), a substrate in which a transparent electrode, a semiconductor element, and the like are formed on a glass substrate is used. For example, in a liquid crystal display (LCD), a substrate in which a transparent electrode, a TFT (Thin Film Transistor), or the like is formed on a glass substrate is used as the substrate.

  Formation of a transparent electrode, a semiconductor element, etc. on a glass substrate is performed in a state where the glass surface opposite to the semiconductor element formation surface of the glass substrate is fixed on the suction stage by vacuum suction. However, when the glass substrate on which the transparent electrode, the semiconductor element and the like are formed is peeled from the adsorption stage, the glass substrate is charged, and electrostatic destruction of the semiconductor element such as a TFT occurs.

  In order to suppress the occurrence of peeling electrification, the surface of the glass substrate in contact with the suction stage is roughened to reduce the contact area between the glass substrate and the suction stage. As a roughening treatment method, for example, a method of chemically treating the surface of a glass substrate by an atmospheric pressure plasma process is known (Patent Document 1).

International Publication No. 2010/128673

  However, since the conventional method does not consider the difference in work function between the glass substrate and the adsorption stage, the occurrence of peeling electrification cannot be sufficiently suppressed, and electrostatic destruction of the semiconductor element may occur.

  The present invention has been made in view of the above-described problems, and provides a glass substrate for display that hardly causes peeling charging when peeling from an adsorption stage, and a method for manufacturing the same.

In the present invention, the average value of the fluorine concentration (mol%) at a depth of 0 to 10 nm from the glass surface opposite to the semiconductor element formation surface of the glass substrate is F 0 to 10 _nm, and the depth from the glass surface is 100 to 400 nm. When the average value of the fluorine concentration (mol%) is F _{100-400 nm} , F _{0-10 nm} / F _{100-400 nm} ≧ 3, and the surface roughness Ra of the glass surface opposite to the semiconductor element formation surface Provided is a glass substrate for display, characterized in that is 0.3 nm or more.

Further, the present invention is a method for manufacturing a glass substrate for a display having a procedure of supplying a gas containing hydrogen fluoride (HF) to one surface of a plate glass conveyed in a heat treatment apparatus,
One surface of the plate glass is a glass surface opposite to the semiconductor element forming surface of the glass substrate,
The gas containing HF has an HF concentration of 0.5 to 30 vol%,
The glass surface temperature which supplies the gas containing the said HF is 500-900 degreeC, The manufacturing method of the glass substrate for displays is provided.

  When the glass substrate for display of the present invention is peeled off from the adsorption stage, it is difficult for peeling electrification to occur.

FIG. 1 is an explanatory view of a method for manufacturing a glass substrate for a display according to an embodiment of the present invention, and is a schematic view showing a configuration example of a heat treatment apparatus. FIG. 2 is an explanatory diagram of the method for manufacturing the glass substrate for display according to the embodiment of the present invention, and is a schematic diagram showing another configuration example of the heat treatment apparatus. FIG. 3 is an explanatory diagram of a method for manufacturing a glass substrate for display according to an embodiment of the present invention, and is a cross-sectional view schematically showing a float glass manufacturing apparatus. FIG. 4 is a diagram illustrating the relationship among the slit width (a), the processing length (b), and the processing width (c) of the injector in the embodiment. FIG. 5 is a graph showing the relationship between the depth from the surface of the glass plate in Example (Examples 4 and 11) and the fluorine concentration in the glass plate. FIG. 6A is a graph showing the relationship between the irradiation light energy X and the square root Y of the number of photoelectrons emitted in the example. FIG. 6B is an enlarged view of FIG. 6A when the irradiation light energy X is 5.5 to 6.0 eV.

[Glass substrate for display]
Hereinafter, the glass substrate for display which concerns on embodiment of this invention is demonstrated.

  The glass composition of the glass substrate for display of this embodiment is not particularly limited, and may be a wide glass composition such as soda lime silicate glass, aluminosilicate glass, borosilicate glass, alkali-free glass, and the like.

In general, contact charging is likely to occur when the work function difference between substances is large. The work function is the minimum amount of energy required to take electrons in a solid out of the solid, precisely into a vacuum. Charges are generated by electrons moving from a material having a low work function to a material having a high work function. The glass substrate is charged due to a work function difference from the adsorption stage.
Therefore, the inventors of the present application focused on the work function of the glass substrate in order to reduce the charge amount of the glass substrate. However, a method for measuring the work function of the glass substrate has not been established.

The inventors of the present application intensively studied and found that the fluorine atom concentration difference between the vicinity of the surface and the inside of the glass substrate is related to the difference in work function between the glass substrate and the adsorption stage.
That is, by increasing the concentration of fluorine atoms having high electronegativity near the surface of the glass substrate, the energy level changes, and the work function of the glass substrate changes.
The amount of charge on the glass substrate is generally determined by the difference in work function between the glass substrate and the adsorption stage (contact charging characteristics of high-resistance insulating glass, Hiroyoshi Kitabayashi, Haruhisa Fujii, Electrical Theory A, 125, 2 No. 179-184, 2005), and it is considered that the difference is reduced by the penetration of fluorine atoms near the surface of the glass substrate.

The glass substrate for display according to the present embodiment has an average fluorine concentration (mol%) at a depth of 0 to 10 nm from the glass surface opposite to the semiconductor element forming surface of the glass substrate, F 0 to 10 _nm. when the average value of the fluorine concentration (mol%) at a depth 100~400nm and F _{100-400 nm} from a _F 0-10nm / F 100-400nm ≧ 3.
As a result, the difference in work function between the glass substrate and the adsorption stage is reduced, and peeling charging of the glass substrate can be suppressed.
Here, the reason why the fluorine concentration in the vicinity of the surface of the glass substrate is F _{0-10 nm} and the fluorine concentration in the glass substrate is F _{100-400 nm} is as described below.
The movement of electrons in contact charging mainly occurs in a region having a depth of 0 to 10 nm from the surface of the glass substrate, and is governed by the interaction between the region and a region having a depth of 100 to 400 nm.
The above F _{0-10 nm} and F _100-400 nm can be measured by X-ray photoelectron spectroscopy (XPS).
In the glass substrate for display of the present embodiment, F _{0-10 nm} / F _{100-400 nm} ≧ 5 is preferable, and F _{0-10 nm} / F _{100-400 nm} ≧ 10 is more preferable.

If the fluorine atom concentration difference between the vicinity of the surface of the glass substrate and the inside of the glass substrate is too large, the haze deteriorates, which is not preferable.
F _{0-10 nm} / F _{100-400 nm} ≦ 150 is preferable because haze deterioration can be suppressed, and F _{0-10 nm} / F _{100-400 nm} ≦ 100 is more preferable.

In addition, the larger the surface roughness of the glass surface, the smaller the contact area between the glass substrate and the adsorption stage and the less the movement of electrons, so that the peeling charge of the glass substrate can be suppressed (high resistance insulation). Contact charging characteristics of glass, Hiroyoshi Kitabayashi, Haruhisa Fujii, Denki Theory A, Vol. 125, No. 2, pp. 179-184, 2005).
In the glass substrate for display of this embodiment, the surface roughness Ra of the glass surface opposite to the semiconductor element forming surface of the glass substrate is 0.3 nm or more.
As a result, the difference in work function between the glass substrate and the adsorption stage is reduced, and peeling charging of the glass substrate can be suppressed.
The surface roughness Ra can be measured by an atomic force microscope (AFM).
The surface roughness Ra is preferably 0.7 nm or more.
However, if the surface roughness Ra is too large, a large defect is generated on the glass surface, which may reduce the strength of the glass substrate. The surface roughness Ra is preferably 5 nm or less because no large defects are generated on the glass surface and the strength of the glass substrate is not lowered. The surface roughness Ra is more preferably 2 nm or less.

In the glass substrate for display of the present embodiment, it is preferable that the peel charge amount measured by the procedure described in Examples described later is −10 kV or more.
Thereby, electrostatic breakdown of the semiconductor element formed on the glass substrate for display is prevented.
The peel charge amount is more preferably −7 kV or more, and further preferably −5 kV or more.

When the irradiation light energy obtained by photoelectron yield spectroscopy (PYS) measurement and the square root of the number of photoelectrons emitted are plotted, the square root of the number of photoelectrons emitted increases rapidly when the irradiation light energy reaches a certain value. At this time, the irradiation light energy which becomes a threshold value is a work function. When the irradiation energy is further increased, the square root of the number of photoelectrons emitted increases linearly.
As a result of intensive studies, the inventors of the present application have found that there is a correlation between this linear increase slope and the peel charge amount of the glass substrate.

In the glass substrate for display of this embodiment, X is 5.5 to 6.0 eV, where X (eV) is the irradiation light energy obtained by photoelectron yield spectroscopy (PYS) measurement, and Y is the square root of the number of photoelectrons emitted. It is preferable that the slope ΔY / ΔX of Y is 10 or more. The work function of the glass substrate is smaller than 5.5 eV. The region where X is 5.5 to 6.0 eV is a region where Y increases linearly.
The gradient ΔY / ΔX approximately represents the density of states of electrons at 5.5 to 6.0 eV. It is considered that as the inclination ΔY / ΔX is larger, the glass substrate is less likely to receive electrons and is less likely to be charged.
The display glass substrate of the present embodiment is more preferably ΔY / ΔX ≧ 20, and more preferably ΔY / ΔX ≧ 50.

Although the dimension of the glass substrate for a display of this embodiment is not specifically limited, In order to suppress the peeling electrification of a glass substrate, it is suitable for a large sized glass substrate. Specifically, it is preferably 2500 mm × 2200 mm or more, and more preferably 3130 mm × 2880 mm or more.
The plate thickness is not particularly limited, but is suitable for a thin glass substrate in order to suppress peeling electrification of the glass substrate. Specifically, it is preferably 1.0 mm or less, more preferably 0.75 mm or less, and further preferably 0.45 mm or less.

It is preferable that the glass substrate for display of this embodiment is an alkali free glass.
Alkali-free glass, by mass percentage based on the following oxides, the SiO ₂ fifty to seventy-three% of _{Al 2 O 3 10.5~24%, B} 2 O 3 and from 0.1 to 12%, the MgO 0 -8%, CaO 0 to 14.5%, SrO 0 to 24%, BaO 0 to 13.5%, ZrO ₂ 0 to 5%, and a combination of MgO, CaO, SrO and BaO. The amount (MgO + CaO + SrO + BaO) is preferably 8 to 29.5%.
In addition, the alkali-free glass is expressed in terms of mass percentage based on the following oxides: SiO ₂ is 58 to 66%, Al ₂ O ₃ is 15 to 22%, B ₂ O ₃ is 5 to 12%, and MgO is 0 to 8%. %, CaO 0 to 9%, SrO 3 to 12.5%, BaO 0 to 2%, and the total amount of MgO, CaO, SrO and BaO (MgO + CaO + SrO + BaO) is 9 to 18% Is preferred.
In addition, the alkali-free glass is expressed in terms of mass percentage based on the following oxides: SiO ₂ is 54 to 73%, Al ₂ O ₃ is 10.5 to 22.5%, and B ₂ O ₃ is 0.1 to 5. 5%, MgO 0-8%, CaO 0-9%, SrO 0-16%, BaO 0-2.5%, and the total amount of MgO, CaO, SrO and BaO (MgO + CaO + SrO + BaO) Is preferably 8 to 26%.

[Method for producing glass substrate for display]
Next, the structural example of the manufacturing method of the glass substrate for displays of this invention is demonstrated.
FIG. 1 is an explanatory view of a method for manufacturing a glass substrate for a display according to an embodiment of the present invention, and is a schematic view showing a configuration example of a heat treatment apparatus.
In the heat treatment apparatus 60 shown in FIG. 1, the plate glass 20 is conveyed in the arrow direction. Although a conveyance means is not specifically limited, For example, it is a conveyance roll which is not illustrated. Moreover, the heat processing apparatus 60 and the heat processing apparatus 62 mentioned later are provided with the heater which is not shown in figure.
Here, the lower surface 22 of the plate glass 20 is a semiconductor element formation surface in the glass substrate for display, and the upper surface 24 of the plate glass 20 is a glass surface opposite to the semiconductor element formation surface. It is fixed on the suction stage by vacuum suction.

A heat treatment apparatus 60 shown in FIG. 1 has an injector 70. The gas blown from the supply port 71 of the injector 70 to the upper surface 24 of the plate glass 20 moves through the flow path 74 in the forward or reverse direction with respect to the moving direction of the plate glass 20 and flows out to the exhaust port 75.
The injector 70 shown in FIG. 1 is a double-flow type injector in which the gas flow from the supply port 71 to the exhaust port 75 is equally divided in the forward direction and the reverse direction with respect to the moving direction of the plate glass 20.

  FIG. 2 is a schematic view showing another configuration example of the heat treatment apparatus. The heat treatment apparatus 62 shown in FIG. 2 has an injector 80. The injector 80 is a single-flow injector. The single-flow type injector is an injector in which the gas flow from the supply port 81 to the exhaust port 85 is fixed in either the forward direction or the reverse direction with respect to the moving direction of the plate glass 20. In the injector 80 shown in FIG. 2, the gas flow 84 from the supply port 81 to the exhaust port 85 is forward with respect to the moving direction of the plate glass 20. However, the present invention is not limited to this, and the gas flow from the supply port 81 to the exhaust port 85 may be in the direction opposite to the moving direction of the plate glass 20.

In the method for manufacturing a glass substrate for display according to the present invention, a gas containing hydrogen fluoride (HF) is supplied to the upper surface 24 of the glass sheet 20 from the supply ports 71 and 81 of the injectors 70 and 80.
As a result, the fluorine concentration in the vicinity of the glass surface on the opposite side of the semiconductor element formation surface is higher than the fluorine concentration inside the glass substrate, and the difference in work function between the glass substrate and the adsorption stage is reduced. Peeling electrification can be suppressed.

In the manufacturing method of the glass substrate for display of this invention, the glass surface temperature which supplies the gas containing HF, ie, the temperature of the upper surface 24 of the plate glass 20, is 500-900 degreeC. By setting the glass surface temperature to 500 ° C. or higher, the following effects can be obtained.
Fluorine enters the vicinity of the glass surface, and the fluorine concentration near the glass surface becomes higher than the fluorine concentration inside the glass substrate. The glass surface temperature is more preferably 550 ° C. or higher, and further preferably 600 ° C. or higher.
Moreover, the following effects are produced by setting the glass surface temperature to 900 ° C. or lower.
The surface roughness Ra of the glass surface is suppressed from becoming too large, and a uniform surface shape is formed.
The glass surface temperature is more preferably 850 ° C. or less, and further preferably 800 ° C. or less.

In the method for producing a glass substrate for display according to the present invention, the gas containing HF is inert such as nitrogen (N ₂ ) or a rare gas from the viewpoint of preventing corrosion of facilities such as the injectors 70 and 80 of the heat treatment apparatuses 60 and 62. A gas is used as a carrier gas and supplied to the upper surface 24 of the glass sheet 20 as a mixed gas with these carrier gases.
The HF concentration of the gas containing HF supplied from the supply ports 71 and 81 of the injectors 70 and 80 is set to 0.5 to 30 vol%. By setting the HF concentration to 0.5 vol% or more, the following effects can be obtained.
Fluorine enters the vicinity of the glass surface, and the fluorine concentration near the glass surface becomes higher than the fluorine concentration inside the glass substrate.
The HF concentration is more preferably 2 vol% or more, and further preferably 4 vol% or more.
Moreover, the following effects are produced by setting the HF concentration to 30 vol% or less.
Generation | occurrence | production of the defect of the glass surface formed by reaction of a glass surface and HF can be suppressed, and it can suppress that the intensity | strength of a glass substrate falls. The HF concentration is more preferably 26 vol% or less, and even more preferably 22 vol% or less.

  The distance D between the supply ports 71 and 81 of the injectors 70 and 80 and the upper surface 24 of the plate glass 20 is preferably 5 to 50 mm. The distance D is more preferably 8 mm or more. The distance D is more preferably 30 mm or less, and still more preferably 20 mm or less. By setting the distance D to be 5 mm or more, contact between the upper surface 24 of the plate glass 20 and the injectors 70 and 80 can be avoided even if the plate glass 20 vibrates due to, for example, an earthquake. On the other hand, by setting the distance D to 50 mm or less, the gas can be prevented from diffusing inside the apparatus, and a sufficient amount of gas can reach the upper surface 24 of the plate glass 20 with respect to the desired gas amount.

  The distance L in the moving direction of the plate glass 20 of the injectors 70 and 80 is preferably 100 to 500 mm. The distance L is more preferably 150 mm or more, and further preferably 200 mm or more. The distance L is more preferably 450 mm or less, and still more preferably 400 mm or less. By setting the distance L to 100 mm or more, the supply ports 71 and 81 and the exhaust ports 75 and 85 can be provided. In particular, the distance L of the injector 70 is preferably 150 mm or more, and the distance L of the injector 80 is preferably 100 mm or more. On the other hand, by setting the distance L to 500 mm or less, the amount of heat removed from the plate glass 20 by the injectors 70 and 80 can be suppressed, so that the outputs of a plurality of heaters can be suppressed.

  The distance in the width direction of the plate glass 20 of the injectors 70 and 80 is preferably greater than the product area of the plate glass 20 in that direction. When implementing the manufacturing method of the glass substrate for a display of this invention as online processing, Preferably it is 3000 mm or more, More preferably, it is 4000 mm or more.

The flow rate (linear velocity) of the gas containing HF is preferably 20 to 300 cm / s. By setting the flow velocity (linear velocity) to 20 cm / s or more, the gas flow containing HF is stabilized and the glass surface can be treated uniformly. The flow velocity (linear velocity) is more preferably 50 cm / s or more, and still more preferably 80 cm / s or more.
Further, as will be described later, when the method for producing a glass substrate for display according to the present invention is implemented as an on-line process, the gas diffuses inside the slow cooling device by setting the flow velocity (linear velocity) to 300 cm / s or less. A sufficient amount of gas can be made to reach the top surface of the glass ribbon in a state where the above is suppressed. The flow velocity (linear velocity) is more preferably 250 cm / s or less, and further preferably 200 cm / s or less.

The manufacturing method of the glass substrate for display of this invention may be implemented as online processing, and may be implemented as offline processing. The term “online processing” in the present specification refers to a case where the method of the present invention is applied in a slow cooling process in which a glass ribbon formed by a float method or a downdraw method is slowly cooled. On the other hand, “offline processing” refers to the case where the method of the present invention is applied to a sheet glass that has been formed and cut into a desired size. Therefore, the plate glass in this specification includes the glass ribbon shape | molded by the float method, the down draw method, etc. in addition to the plate glass shape | molded and cut by the desired magnitude | size.
The method for producing a glass substrate for display of the present invention is preferably carried out as an on-line process for the following reason.
In the case of offline processing, it is necessary to increase the number of processes, whereas in the case of online processing, it is not necessary to increase the number of processes, so that processing can be performed at low cost. Moreover, in the case of off-line processing, the gas containing HF wraps around between the glass substrates to the semiconductor element forming surface of the glass substrate, whereas in the case of the on-line processing of the glass ribbon, the HF-containing gas is prevented from wrapping in. be able to.

The manufacturing procedure of the plate glass such as the glass substrate for display includes the melting step of melting the glass raw material to form molten glass, the molding step of forming the molten glass obtained in the melting step into a strip to form a glass ribbon, and the above And a slow cooling step of slowly cooling the glass ribbon obtained in the molding step. Examples of the molding step include a float molding step by a float method and a downdraw molding step by a downdraw method.
When implementing the manufacturing method of the glass substrate for a display of this invention as online processing, the gas containing HF is supplied with respect to the top surface of a glass ribbon in the said slow cooling process.

  FIG. 3 is an explanatory diagram of a method for manufacturing a glass substrate for display according to an embodiment of the present invention, and is a cross-sectional view schematically showing a float glass manufacturing apparatus.

  A float glass manufacturing apparatus 100 shown in FIG. 3 includes a melting apparatus 200 that melts a glass raw material 10 to form a molten glass 12, and a molding apparatus that forms the molten glass 12 supplied from the melting apparatus 200 into a strip shape to form a glass ribbon 14. 300 and a slow cooling device 400 that slowly cools the glass ribbon 14 molded by the molding device 300.

  The melting apparatus 200 includes a melting tank 210 that stores the molten glass 12 and a burner 220 that forms a flame above the molten glass 12 that is stored in the melting tank 210. The glass raw material 10 thrown into the melting tank 210 is gradually melted into the molten glass 12 by the radiant heat from the flame formed by the burner 220. The molten glass 12 is continuously supplied from the melting tank 210 to the molding apparatus 300.

  The molding apparatus 300 includes a bathtub 320 that accommodates molten tin 310. The forming apparatus 300 forms the glass ribbon 14 by forming the molten glass 12 continuously supplied onto the molten tin 310 into a strip shape by causing the molten glass 12 to flow in a predetermined direction on the molten tin 310. The atmosphere temperature in the molding apparatus 300 becomes lower as it goes from the inlet to the outlet of the molding apparatus 300. The atmospheric temperature in the molding apparatus 300 is adjusted by a heater (not shown) provided in the molding apparatus 300. The glass ribbon 14 is cooled while flowing in a predetermined direction, and is pulled up from the molten tin 310 in the downstream area of the bathtub 320. The glass ribbon 14 pulled up from the molten tin 310 is conveyed to the slow cooling device 400 by the lift-out roll 510.

  The slow cooling device 400 gradually cools the glass ribbon 14 formed by the forming device 300. The slow cooling device 400 includes, for example, a slow cooling furnace (rare) 410 having a heat insulating structure and a plurality of transport rolls 420 disposed in the slow cooling furnace 410 and transporting the glass ribbon 14 in a predetermined direction. The atmospheric temperature in the slow cooling furnace 410 becomes lower as it goes from the inlet to the outlet of the slow cooling furnace 410. The atmospheric temperature in the slow cooling furnace 410 is adjusted by a heater 440 or the like provided in the slow cooling furnace 410. The glass ribbon 14 carried out from the outlet of the slow cooling furnace 410 is cut into a predetermined size by a cutting machine and shipped as a product.

Before shipping as a product, if necessary, at least one of both surfaces of the glass substrate may be polished to clean the glass substrate. In addition, when the manufacturing method of the glass substrate for a display of this invention is implemented as online processing, the glass surface on the opposite side to the semiconductor element formation surface of a glass substrate respond | corresponds to the top surface of the glass ribbon 14, and a semiconductor element formation surface Corresponds to the bottom surface of the glass ribbon 14.
In the method for producing a glass substrate for display according to the present invention, the work of the glass substrate and the adsorption stage is achieved by increasing the fluorine concentration in the vicinity of the glass surface opposite to the semiconductor element forming surface as compared with the fluorine concentration inside the glass substrate. In order to reduce the difference in function and suppress the peeling charge of the glass substrate, it is preferable to polish only the bottom surface of the glass ribbon 14 when polishing. The semiconductor element forming surface of the glass substrate is polished by a polishing tool while supplying a cerium oxide aqueous solution. At the time of polishing, a part of the aqueous cerium oxide solution wraps around the glass surface opposite to the semiconductor element formation surface of the glass substrate and becomes a slurry residue.

  The glass substrate is cleaned by, for example, shower cleaning, slurry cleaning using a disk brush, or shower rinsing. Slurry cleaning is performed by polishing with a disk brush while supplying slurry (for example, cerium oxide aqueous solution or calcium carbonate aqueous solution) to the glass surface opposite to the semiconductor element forming surface of the glass substrate. The slurry residue remaining on the opposite glass surface is removed.

In the float glass manufacturing apparatus 100 shown in FIG. 3, injectors 70 and 80 are installed above the glass ribbon 14 in the slow cooling apparatus 400 in order to implement the method for manufacturing a glass substrate for display of the present invention as an online process. The gas containing hydrogen fluoride (HF) is supplied to the top surface of the glass ribbon 14 using the injectors 70 and 80. 1 and 2 correspond to the slow cooling apparatus 400 shown in FIG. 3 when the display glass substrate manufacturing method of the present invention is implemented as an online process.
Moreover, in FIG. 3, although the injectors 70 and 80 are installed in the slow cooling apparatus 400, the float glass manufacturing apparatus which concerns on another embodiment of this invention is the glass surface temperature which supplies the gas containing HF. If it is 500-900 degreeC, you may install an injector in the shaping | molding apparatus 300. FIG.

Examples of the present invention and comparative examples will be specifically described below. The present invention is not limited to these descriptions.
(Experimental example 1)
In Experimental example 1, the manufacturing method of the glass substrate for a display of this invention was implemented as offline process.
In Experimental Example 1, SiO ₂ : 59.5%, Al ₂ O ₃ : 17%, B ₂ O ₃ : 8%, MgO: 3.3%, CaO: 4%, SrO: 7.6%, BaO: 0.1%, ZrO ₂ : 0.1%, MgO + CaO + SrO + BaO: 15%, the balance being inevitable impurities, and the total content of alkali metal oxides being 0.1% or less An alkali-free glass plate (520 mm × 410 mm × thickness 0.5 mm) was prepared. A gas containing HF was supplied to the upper surface of the alkali-free glass plate from the injector 70 of the heat treatment apparatus shown in FIG. FIG. 4 is a diagram showing a relationship among the slit width (a), the processing length (b), and the processing width (c) of the injector in Experimental Example 1.
In Experimental Example 1, the flow rate (L / min), processing time (sec), and linear velocity (mm / sec) of the gas containing a (mm), b (mm), c (mm), and HF are as follows. The conditions shown in Table 1 were used.
The distance D between the supply port 71 of the injector 70 and the upper surface of the glass plate 20 was set to 10 mm.
The glass surface temperature (described as temperature in Table 2) and the HF concentration (vol%) when supplying a gas containing HF were the conditions shown in Table 2 below. In Table 2, Examples 1 and 2 are comparative examples, and Examples 3 and 4 are examples.
After supplying the gas containing HF, the glass surface temperature was kept at the same temperature for 5 minutes, and then cooled to room temperature over 30 minutes.
Thereafter, the following evaluation was performed.

[F concentration near the surface of glass substrate and inside (F _{0-10 nm} , F _{100-400 nm} )]
F _{0-10 nm} and F _{100-400 nm} were measured by the following procedure.
The glass substrate obtained by the above procedure is cut into a width of 10 mm and a length of 10 mm, and the F concentration (mol%) at depths 0, 2, 5, 7, and 10 nm from the glass surface of the glass substrate is measured by X-ray photoelectron spectroscopy. It measured with the apparatus (The product made from ULVAC-PHI, ESCA5500). The measured values of F concentration at depths of 0, 2, 5, 7, and 10 _nm were averaged, and the average value F _{0-10 nm} of F concentration at depths of 0 to 10 _nm was calculated. Grinding from the glass substrate surface to a depth of 10 nm was sputter-etched with a C ₆₀ ion beam.
In addition, F concentration at a depth of 100, 101, 112, 123, 134, 145, 156, 167, 178, 189, 200, 211, 222, 266, 310, 354, 398, 400 nm from the glass surface of the glass substrate ( Mol%) was measured with an X-ray photoelectron spectrometer (manufactured by ULVAC-PHI, ESCA5500). The measured values of the F concentration at a depth of 100 to 400 _nm were _averaged to calculate an average value F _100-400 nm of the F concentration at a depth of 100 to 400 nm.
The relationship between the depth from the surface of the glass plate in Example 4 and the fluorine concentration in the glass plate is shown in FIG.

[Average surface roughness Ra of glass surface]
The glass substrate obtained by the above procedure is cut into a width of 5 mm and a length of 5 mm, and the average surface roughness Ra (arithmetic average surface roughness Ra (JIS B0601-2013)) of the glass surface of the glass substrate is determined by the following method. Measured with The glass surface of the glass substrate was observed using an atomic force microscope (product name: SPI-3800N, manufactured by Seiko Instruments Inc.). SI-DF40P2 was used as the cantilever. Observation was performed on a scan area of 5 μm × 5 μm using a dynamic force mode at a scan rate of 1 Hz (number of data in area: 256 × 256). Based on this observation, the average surface roughness Ra at each measurement point was calculated. As the calculation software, software attached to the atomic force microscope (software name: SPA-400) was used.

[Peeling charge of glass substrate]
The peel charge amount of the glass substrate obtained by the above procedure was measured by the following method. A glass substrate having a width of 410 mm × a length of 520 mm × a thickness of 0.5 mm was brought into contact with a vacuum suction stage made of SUS304, and then the suction and release of the glass substrate were repeated 110 cycles. Thereafter, the glass substrate was peeled off from the vacuum suction stage using lift pins. The change in surface potential until the glass substrate was lifted 5 cm away from the vacuum adsorption stage was measured with a surface potentiometer (product name: MODEL 341B, manufactured by Trek Japan). The peak value of the measurement result was defined as the peel charge amount.

[PYS measurement (ΔY / ΔX)]
About Example 4, the photoelectron yield spectroscopy (PYS) measurement was implemented in the following procedure, and the inclination ((DELTA) Y / (DELTA) X) of irradiation light energy X and the square root Y of the number of photoelectron emission was calculated | required.
A glass substrate having a width of 20 mm, a length of 20 mm, and a thickness of 0.5 mm was prepared. The ultraviolet irradiation surface was the glass surface opposite to the semiconductor element formation surface of the glass substrate. The number of photoelectrons emitted from the irradiated surface was measured using an atmospheric photoelectron spectrometer AC-5 (manufactured by Riken Keiki Co., Ltd.). The irradiation ultraviolet intensity was 2000 nW. Ultraviolet rays were irradiated in increments of 0.1 eV with an irradiation light energy X in the range of 4.2 to 6.2 eV. The photoelectron counting time was set to 5 seconds per 0.1 eV.
A graph showing the relationship between the irradiation light energy X and the square root Y of the number of photoelectrons emitted in Example 4 is shown in FIG. FIG. 6B is an enlarged view of FIG. 6A when the irradiation light energy X is 5.5 to 6.0 eV. The slope ΔY / ΔX was calculated by linearly approximating a plot when X was 5.5 to 6.0 eV by the least square method.

(Experimental example 2)
In Experimental Example 2, the method for producing a glass substrate for display according to the present invention was performed as online processing.
In Experimental Example 2, using the float glass manufacturing apparatus 100 shown in FIG. 3, SiO ₂ : 59.5%, Al ₂ O ₃ : 17%, B ₂ O ₃ : 8%, MgO: 3.3%, CaO : 4%, SrO: 7.6%, BaO: 0.1%, ZrO ₂ : 0.1%, MgO + CaO + SrO + BaO: 15%, the balance being unavoidable impurities, A non-alkali glass plate having a thickness of 0.5 mm and a total content of 0.1% or less was produced.

After melting the glass raw material 10 with the melting apparatus 200 to make the molten glass 12, the molten glass 12 was supplied to the molding apparatus 300, and the molten glass 12 was formed into a strip shape to obtain a glass ribbon 14. After pulling out the glass ribbon 14 from the outlet of the molding apparatus 300, the glass ribbon 14 was gradually cooled in the slow cooling apparatus 400.
An injector 70 having a distance L in the moving direction of the glass ribbon 14 of 300 mm was installed at a position where the temperature of the glass ribbon 14 in the slow cooling device 400 was 500 ° C.
FIG. 4 is a diagram showing a relationship among the slit width (a), the processing length (b), and the processing width (c) of the injector in Experimental Example 2.
In Experimental Example 2, the flow rate (L / min), processing time (sec), and linear velocity (mm / sec) of the gas containing a (mm), b (mm), c (mm), and HF are as follows. The conditions shown in Table 2 were used.
The distance D between the supply port 71 of the injector 70 and the upper surface of the glass plate 20 was set to 10 mm.
Further, the glass surface temperature (described as temperature in Table 3) and the HF concentration (vol%) when supplying a gas containing HF were set to the conditions shown in Table 3 below. In Table 3, Example 11 is a comparative example, and Examples 12 and 13 are examples.
The obtained glass plate was evaluated in the same procedure as in Experimental Example 1. The relationship between the depth from the surface of the glass plate in Example 11 and the fluorine concentration in the glass plate is shown in FIG.
Graphs showing the relationship between the irradiation light energy X and the square root Y of the number of photoelectrons emitted in Examples 11 and 13 are shown in FIGS. 6 (a) and 6 (b).

_F 0-10nm / F 100-400nm <3 or Ra examples below 0.3 nm 1, 2,, Example 11, separation charge is less than -10 kV. On the other hand, in Examples 3, 4, 12 and 13 in which F _{0-10 nm} / F _100-400 nm ≧ 3 and Ra is 0.3 nm or more, the peel charge amount is suppressed, and at −10 kV or more there were. In Example 11, ΔY / ΔX <10, whereas in Examples 4, 12, and 13, ΔY / ΔX ≧ 10.

DESCRIPTION OF SYMBOLS 10 Glass raw material 12 Molten glass 14 Glass ribbon 20 Plate glass 22 Lower surface 24 Upper surface 60, 62 Heat processing apparatus 70, 80 Injector 71, 81 Supply port 74, 84 Flow path 75, 85 Exhaust port 100 Float glass manufacturing apparatus 200 Melting apparatus 210 Melting tank 220 Burner 300 Molding device 310 Molten tin 320 Bath 400 Slow cooling device 410 Slow cooling furnace 420 Conveying roll 440 Heater 510 Lift out roll

Claims (6)

The average value of fluorine concentration (mol%) at a depth of 0 to 10 nm from the glass surface opposite to the semiconductor element formation surface of the glass substrate is F _{0-10 nm,} and the fluorine concentration at a depth of 100 to 400 nm from the glass surface ( mol%) is F _{100-400 nm} , F _{0-10 nm} / F _{100-400 nm} ≧ 3, and the surface roughness Ra of the glass surface opposite to the semiconductor element formation surface is 0.3 nm. It is the above, The glass substrate for displays characterized by the above-mentioned.   The glass substrate for a display according to claim 1, wherein the peel charge amount is −10 kV or more.   When the irradiation light energy in the photoelectron yield spectroscopy (PYS) measurement is X (eV) and the square root of the number of photoelectrons emitted is Y, the Y slope ΔY / ΔX when the X is 5.5 to 6.0 eV is 10 The glass substrate for display according to claim 1 or 2, which is as described above. A method for producing a glass substrate for a display having a procedure of supplying a gas containing hydrogen fluoride (HF) to one surface of a plate glass conveyed in a heat treatment apparatus,
One surface of the plate glass is a glass surface opposite to the semiconductor element forming surface of the glass substrate,
The gas containing HF has an HF concentration of 0.5 to 30 vol%,
The glass surface temperature which supplies the gas containing the said HF is 500-900 degreeC, The manufacturing method of the glass substrate for displays characterized by the above-mentioned. A melting step of melting glass raw material to form molten glass, a molding step of forming the molten glass obtained in the melting step into a strip to form a glass ribbon, and a step of gradually cooling the glass ribbon obtained in the molding step A cooling process,
The manufacturing method of the glass substrate for a display of Claim 4 which supplies the gas containing HF with respect to the top surface of the said glass ribbon in the said slow cooling process.   The manufacturing method of the glass substrate for a display of Claim 4 or 5 whose said shaping | molding process is a float shaping | molding process.