Crystallized glass, chemically strengthened glass, and semiconductor supporting substrate

Abstract

To provide a crystallized glass having superior transparency and chemical strengthening properties.SOLUTION: The present invention relates to a chemically strengthened glass having a compressive stress layer on a surface, with a visible-light transmittance of 85% or more in terms of a thickness of 0.7 mm, and a haze value of 0.5% or less in terms of a thickness of 0.7 mm, a depth of the compressive stress layer of 80 μm or more, a compressive stress value at the surface of 490 MPa or more, and a compressive stress value at a depth of 50 μm from the surface of 100 MPa or more. The chemically strengthened glass is crystallized glass including, in mass% on an oxide basis: 45% or more of SiO2, 1% or more of Al2O3, 10% or more of Li2O, 1-15% of ZrO2, 0.5-12% of P2O5, and 0.1-10% of Na2O.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a crystallized glass, a chemically strengthened glass, and a semiconductor support substrate. [Background technology]

[0002] Chemically strengthened glass is used for the cover glass of mobile terminals and the like.

[0003] Chemically strengthened glass is produced by, for example, bringing glass into contact with a molten salt containing alkali metal ions to cause ion exchange between the alkali metal ions in the glass and the alkali metal ions in the molten salt, thereby forming a compressive stress layer on the glass surface.

[0004] Crystallized glass is glass in which crystals are precipitated, and is harder and less susceptible to damage than amorphous glass, which does not contain crystals. Patent Document 1 describes an example of chemically strengthening crystallized glass by ion exchange treatment. However, crystallized glass is inferior to amorphous glass in terms of transparency.

[0005] Patent Document 2 describes transparent crystallized glass. However, few transparent crystallized glasses have high transparency suitable for cover glass. In addition, the chemical strengthening properties of crystallized glass are strongly influenced by the glass composition and precipitated crystals. The scratch resistance and transparency of crystallized glass are also strongly influenced by the glass composition and precipitated crystals. Therefore, in order to obtain crystallized glass that is excellent in both chemical strengthening properties and transparency, delicate adjustment of the glass composition and precipitated crystals is required.

[0006] Meanwhile, in the field of semiconductor packages, technologies such as wafer level packaging (WLP) and panel level packaging (PLP) have been attracting attention in manufacturing (see Patent Document 2). This technology is a technology in which, for example, a silicon chip is placed on a glass substrate and sealed by molding with sealing resin.

[0007] In this case, the support substrate may be peeled off during the manufacturing process. A glass substrate is widely used as the support substrate. Since the glass substrate is transparent, it can be peeled off by irradiating it with a laser beam. The glass substrate used as the support substrate must be resistant to breakage during the packaging process, must not scatter fragments if it is broken, and must have thermal expansion matching with the semiconductor. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japan Special Publication No. 2016-529201 [Patent Document 2] Japanese Patent Application Publication No. 2016-160136 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention provides crystallized glass having excellent transparency and chemical strengthening properties, and also provides chemically strengthened glass having a large thermal expansion coefficient, excellent transparency and strength, and being less likely to shatter when broken. [Means for solving the problem]

[0010] The present invention relates to a crystallized glass having a visible light transmittance of 85% or more converted to a thickness of 0.7 mm, a haze value of 1.0% or less converted to a thickness of 0.7 mm, and a mass % based on oxides. SiO 2 45 to 70% Al 2 O 3 1 to 15% Li 2 The present invention provides a crystallized glass containing 10 to 25% O.

[0011] The present invention also relates to a chemically strengthened glass having a compressive stress layer on its surface, the glass having a visible light transmittance converted to a thickness of 0.7 mm of 85% or more, a haze value converted to a thickness of 0.7 mm of 0.5% or less, a surface compressive stress value of 500 MPa or more, and a compressive stress layer depth of 80 μm or more, expressed in mass% on an oxide basis. SiO 2 45 to 70% Al 2 O 3 1 to 15% Li 2 The present invention provides a chemically strengthened glass, which is a crystallized glass containing 10 to 25% O.

[0012] The present invention also provides a semiconductor support substrate made of the above crystallized glass or the above chemically strengthened glass. Effect of the Invention

[0013] According to the present invention, it is possible to obtain crystallized glass having excellent transparency and chemical strengthening properties. In addition, it is possible to obtain chemically strengthened glass having a large thermal expansion coefficient, excellent transparency and strength, and being less likely to scatter into pieces when broken. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing an example of a stress profile of chemically strengthened glass. [Diagram 2] FIG. 2 is a diagram showing an example of a powder X-ray diffraction pattern of the crystallized glass. [Diagram 3] FIG. 3 is a diagram showing an example of a powder X-ray diffraction pattern of the crystallized glass. [Figure 4] FIG. 4 is a diagram showing an example of a DSC curve of the amorphous glass according to the present invention. [Diagram 5] 5A and 5B show a supporting glass according to one embodiment of the present invention to be bonded to a semiconductor substrate, where FIG. 5A is a cross-sectional view before bonding and FIG. 5B is a cross-sectional view after bonding. [Figure 6] FIG. 6 shows a cross-sectional view of a laminated substrate according to one embodiment of the present invention. [Figure 7]FIG. 7 is a diagram showing an example of a TEM image of crystallized glass. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] In this specification, unless otherwise specified, the use of "to" indicating a numerical range means that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0016] In this specification, "amorphous glass" and "crystallized glass" are collectively referred to as "glass". In this specification, "amorphous glass" refers to glass that does not show diffraction peaks indicating crystals by powder X-ray diffraction. "Crystallized glass" refers to "amorphous glass" that is heat-treated to precipitate crystals, and contains crystals.

[0017] In the powder X-ray diffraction measurement, measurements are made using CuKα radiation in the range of 2θ of 10° to 80°, and when a diffraction peak appears, the precipitated crystals are identified by, for example, the three strongest radiation method.

[0018] In the following, "chemically strengthened glass" refers to glass after chemical strengthening treatment, and "glass for chemical strengthening" refers to glass before chemical strengthening treatment.

[0019] In addition, the "mother composition of chemically strengthened glass" refers to the glass composition of glass for chemical strengthening, and except for cases where extreme ion exchange treatment has been performed, the glass composition deeper than the compressive stress layer depth DOL of the chemically strengthened glass is the mother composition of the chemically strengthened glass.

[0020] In this specification, unless otherwise specified, glass compositions are expressed in mass % based on oxides, and mass % is simply represented as "%".

[0021] In addition, in this specification, "substantially free" means that the content is below the impurity level contained in raw materials, that is, that it is not intentionally added. Specifically, for example, it is less than 0.1%.

[0022] In this specification, the term "stress profile" refers to a representation of compressive stress values ​​with the depth from the glass surface as a variable. An example is shown in Figure 1. In the stress profile, tensile stress is represented as negative compressive stress.

[0023] The "compressive stress value (CS)" can be measured by cutting a cross section of glass into thin slices and analyzing the sliced ​​samples with a birefringence imaging system. A birefringence imaging system birefringence stress meter is a device that measures the magnitude of retardation caused by stress using a polarizing microscope and a liquid crystal compensator, etc., and one example is the birefringence imaging system Abrio-IM manufactured by CRi.

[0024] Measurements can also be made using scattered light photoelasticity. With this method, light is incident on the glass surface, and the polarization of the scattered light is analyzed to measure CS. Examples of stress measuring instruments that use scattered light photoelasticity include the scattered light photoelasticity meters SLP-1000 and SLP-2000 manufactured by Orihara Seisakusho.

[0025] In this specification, the "depth of compressive stress layer (DOL)" is the depth at which the compressive stress value becomes zero. Hereinafter, the surface compressive stress value is referred to as CS 0 , the compressive stress value at a depth of 50 μm is CS 50 Also, "internal tensile stress (CT)" refers to the tensile stress value at a depth of 1 / 2 the plate thickness t.

[0026] In this specification, "light transmittance" refers to the average transmittance of light with a wavelength of 380 nm to 780 nm. Furthermore, "haze value" is measured using a C light source in accordance with JIS K3761:2000.

[0027] In this specification, the color of crystallized glass is the color obtained from the transmission spectrum of a crystallized glass plate sample having a thickness of 0.7 mm under light source C, and is expressed using the tristimulus values ​​X, Y, and Z in the XYZ color system defined in JIS Z8701:1999 and its appendix, or the dominant wavelength λd and excitation purity Pe calculated from these values.

[0028] In this specification, the term "Vickers hardness" refers to the Vickers hardness (HV0.1) defined in JIS R1610:2003.

[0029] The "fracture toughness value" can be measured by the DCDC method (Acta metall. mater. Vol. 43, pp. 3453-3458, 1995).

[0030] In this specification, the term "semiconductor" refers not only to semiconductor wafers such as silicon or semiconductor chips, but also to composites including chips, wiring layers, and molding resin.

[0031] <Glass-ceramics> The thickness (t) of the crystallized glass is preferably 3 mm or less from the viewpoint of enabling a significant improvement in strength by chemical strengthening, and more preferably, is 2 mm or less, 1.6 mm or less, 1.1 mm or less, 0.9 mm or less, 0.8 mm or less, and 0.7 mm or less in the following stepwise manner. Moreover, the thickness (t) is preferably 0.3 mm or more, more preferably 0.4 mm or more, and even more preferably 0.5 mm or more in order to obtain sufficient strength by chemical strengthening treatment.

[0032] This crystallized glass has a light transmittance of 85% or more when the thickness is 0.7 mm, so when used as a cover glass for a mobile display, the display screen is easy to see. A light transmittance of 88% or more is preferable, and 90% or more is more preferable. The higher the light transmittance, the better, but it is usually 91% or less. 90% is equivalent to ordinary amorphous glass.

[0033] In addition, the haze value is 1.0% or less when the thickness is 0.7 mm, preferably 0.4% or less, more preferably 0.3% or less, even more preferably 0.2% or less, and particularly preferably 0.15% or less. The smaller the haze value, the better, but if the crystallization rate or the crystal grain size is reduced to reduce the haze value, the mechanical strength decreases. In order to increase the mechanical strength, the haze value when the thickness is 0.7 mm is preferably 0.02% or more, more preferably 0.03% or more.

[0034] The Y value of the present crystallized glass in the XYZ color system is preferably 87 or more, more preferably 88 or more, even more preferably 89 or more, and particularly preferably 90 or more. When used as a cover glass for a mobile display, it is preferable that the coloring of the glass itself is suppressed as much as possible in order to improve the reproducibility of the displayed color when used on the display screen side, and to maintain the design when used on the housing side. Therefore, the excitation purity Pe of the present crystallized glass is preferably 1.0 or less, more preferably 0.75 or less, even more preferably 0.5 or less, particularly preferably 0.35 or less, and most preferably 0.25 or less.

[0035] When this glass-ceramic or tempered glass made by tempering it is used as the cover glass of a mobile display, it is preferable that it has a texture and a high-quality feel different from plastic. Therefore, the dominant wavelength λd of this glass-ceramic is preferably 580 nm or less, and the refractive index is preferably 1.52 or more, more preferably 1.55 or more, and even more preferably 1.57 or more.

[0036] The present crystallized glass is preferably a crystallized glass containing lithium metasilicate crystals. The lithium metasilicate crystals are Li 2 SiO 3 Generally, it is a crystal that shows diffraction peaks at Bragg angles (2θ) of 26.98°, 18.88°, and 33.05° in the powder X-ray diffraction spectrum. Figure 2 shows an example of the X-ray diffraction spectrum of this glass-ceramic, in which lithium metasilicate crystals can be seen.

[0037] The present glass-ceramics preferably contain lithium phosphate crystals. The lithium phosphate crystals are Li 3 PO 4This crystal has diffraction peaks at Flag angles (2θ) of 22.33°, 23.18°, and 33.93° in the powder X-ray diffraction spectrum. Figure 3 shows an example of the powder X-ray diffraction spectrum of this crystallized glass, in which lithium metasilicate crystals and lithium phosphate crystals are clearly visible. Comparing Figures 2 and 3, it can be seen that lithium phosphate crystals are also present in the case of Figure 2. The precipitation of lithium phosphate crystals tends to increase chemical durability.

[0038] The present crystallized glass may contain both lithium metasilicate crystals and lithium phosphate crystals.

[0039] The present crystallized glass can be obtained by heat treating and crystallizing an amorphous glass, which will be described later.

[0040] Glass-ceramics containing lithium metasilicate crystals have a higher fracture toughness value than general amorphous glass, and are less likely to break violently even when a large compressive stress is applied by chemical strengthening. In amorphous glass in which lithium metasilicate crystals can precipitate, lithium disilicate may precipitate depending on the heat treatment conditions. Lithium disilicate is Li 2 S 2 O 5 and generally, it is a crystal that exhibits diffraction peaks at Bragg angles (2θ) of approximately 24.89°, 23.85°, and 24.40° in a powder X-ray diffraction spectrum.

[0041] When lithium disilicate crystals are contained, it is preferable that the lithium disilicate crystal particle size (also abbreviated as crystal size) calculated from the X-ray diffraction peak width by the Scherrer formula is 45 nm or less, since transparency is easily obtained, and 40 nm or less is more preferable.

[0042] However, when lithium metasilicate crystals and lithium disilicate crystals are simultaneously contained in the crystallized glass, the transparency of the crystallized glass is likely to decrease, so it is preferable that the crystallized glass does not contain lithium disilicate. Here, "does not contain lithium disilicate" means that the diffraction peak of lithium disilicate crystals is not detected in the X-ray diffraction spectrum.

[0043] The crystallization rate of the present crystallized glass is preferably 5% or more, more preferably 10% or more, even more preferably 15% or more, and particularly preferably 20% or more in order to increase mechanical strength. In order to increase transparency, it is preferably 70% or less, more preferably 60% or less, and particularly preferably 50% or less. A small crystallization rate is also excellent in that it is easy to bend and mold by heating. Here, the crystallization rate of the crystallized glass in which lithium metasilicate crystals and lithium phosphate crystals are precipitated, for example, refers to the crystallization rate of lithium metasilicate crystals and lithium phosphate crystals combined.

[0044] The crystallinity can be calculated from the X-ray diffraction intensity by the Rietveld method. The Rietveld method is described in the "Crystal Analysis Handbook" (Kyoritsu Shuppan, 1999, pp. 492-499), edited by the Editorial Committee of the "Crystal Analysis Handbook" of the Japanese Crystallographic Society.

[0045] The average particle size of the precipitated crystals of the present crystallized glass is preferably 80 nm or less, more preferably 60 nm or less, even more preferably 50 nm or less, particularly preferably 40 nm or less, and most preferably 30 nm or less. The average particle size of the precipitated crystals is determined from a transmission electron microscope (TEM) image. The average particle size of the precipitated crystals can be estimated from a scanning electron microscope (SEM) image.

[0046] The average thermal expansion coefficient of this crystallized glass at 50℃ to 350℃ is 90×10 -7 °C or higher is preferable, and 100 x 10 -7 °C or higher is more preferable, and 110 × 10 -7 °C or higher is more preferable, and 120 × 10 -7 ° C. or higher is particularly preferable, and 130 × 10 -7°C or higher is most preferred.

[0047] If the thermal expansion coefficient is too large, cracks may occur due to the difference in the thermal expansion coefficient during the chemical strengthening process. Therefore, it is preferable to set the thermal expansion coefficient at 160×10 -7 °C or less, more preferably 150 × 10 -7 °C or less, more preferably 140 × 10 -7 °C or less.

[0048] Furthermore, such a thermal expansion coefficient makes the material suitable as a support substrate for semiconductor packages that contain a large amount of resin.

[0049] The present crystallized glass contains crystals, so it has high hardness. Therefore, it is difficult to scratch and has excellent abrasion resistance. In order to increase the abrasion resistance, the Vickers hardness is preferably 600 or more, more preferably 700 or more, even more preferably 730 or more, particularly preferably 750 or more, and most preferably 780 or more.

[0050] If the hardness is too high, processing becomes difficult, so the Vickers hardness of the present crystallized glass is preferably 1100 or less, more preferably 1050 or less, and even more preferably 1000 or less.

[0051] The Young's modulus of the present crystallized glass is preferably 85GPa or more, more preferably 90GPa or more, even more preferably 95GPa or more, and particularly preferably 100GPa or more, in order to suppress warpage during chemical strengthening. The present crystallized glass may be polished before use. In order to facilitate polishing, the Young's modulus is preferably 130GPa or less, more preferably 125GPa or less, and even more preferably 120GPa or less.

[0052] The fracture toughness of this glass-ceramic is 0.8 MPa m 1 / 2 More preferably, 0.85 MPa m 1 / 2 More preferably, 0.9 MPa m 1 / 2 If the thickness is more than this, then when chemically strengthened, fragments are less likely to scatter when broken, which is preferable.

[0053] The relative dielectric constant ε of this crystallized glass at a frequency of 10GHz is preferably 8.0 or less, because when this crystallized glass is used in wireless communication equipment for high-frequency communication, communication efficiency is good. The relative dielectric constant ε of this crystallized glass at a frequency of 10GHz is more preferably 7.6 or less, and even more preferably 7.3 or less. Moreover, ε is usually 3.7 or more.

[0054] The dielectric loss tangent tanδ of the present crystallized glass at a frequency of 10 GHz is smaller than that of non-crystallized glass, which is preferable. This is because crystals with a lower tanδ than glass are precipitated in the glass, so that the overall tanδ is smaller. If tanδ is 0.014 or less, the communication efficiency is improved when the present crystallized glass is used in a wireless communication device for high-frequency communication, so it is preferable. The dielectric loss tangent tanδ of the present crystallized glass at a frequency of 10 GHz is more preferably 0.012 or less, more preferably 0.010 or less, and even more preferably 0.008 or less. Moreover, tanδ is usually 0.002 or more.

[0055] Since the glass composition of the present crystallized glass is the same as the composition of the amorphous glass before crystallization, it will be explained in the section on amorphous glass.

[0056] <Chemically strengthened glass> The chemically strengthened glass obtained by chemically strengthening the present glass-ceramics (hereinafter, sometimes referred to as the present strengthened glass) has a surface compressive stress value CS 0 The surface compressive stress value of the present tempered glass is preferably 600 MPa or more, since the glass is less likely to break due to deformation such as bending. The surface compressive stress value of the present tempered glass is more preferably 800 MPa or more.

[0057] The present tempered glass is preferable because it is less likely to break even when the surface is scratched due to the compressive stress layer depth DOL of 80 μm or more. The DOL is preferably 100 μm or more.

[0058] In addition, the compressive stress value CS at a compressive stress layer depth of 50 μm 50The larger CS is, the greater the strength in the sandpaper drop test described below, i.e., the higher the drop strength. 50 is preferably 80 MPa or more, more preferably 100 MPa or more, further preferably 120 MPa or more, and particularly preferably 140 MPa or more.

[0059] (Sandpaper drop test) The glass plate to be evaluated (120mm x 60mm x 0.7mm) is treated as the cover glass of a smartphone, attached to a case simulating a smartphone, and dropped onto a flat SiC#180 sandpaper surface. The combined mass of the glass plate and case is approximately 140g.

[0060] The test is started from a height of 30cm, and if the chemically strengthened glass plate does not break, the test is repeated from a height of 10cm, and the height at which it breaks (unit: cm) is recorded. This test is counted as one set, and 10 sets are repeated, and the average height at which it breaks is the "drop height."

[0061] The drop height of this tempered glass in a sandpaper drop test is preferably 80 cm or more.

[0062] The internal tensile stress (CT) of the present tempered glass is preferably 110 MPa or less, since scattering of fragments is suppressed when the chemically tempered glass breaks. The CT is more preferably 100 MPa or less, and even more preferably 90 MPa or less. On the other hand, if the CT is made small, the surface compressive stress becomes small, and it tends to be difficult to obtain sufficient strength. Therefore, the CT is preferably 50 MPa or more, more preferably 55 MPa or more, and even more preferably 60 MPa or more.

[0063] The four-point bending strength of the tempered glass is preferably 500 MPa or more, more preferably 550 MPa or more, and even more preferably 600 MPa or more. Here, the four-point bending strength is measured using a test piece of 40 mm x 5 mm x 0.8 mm, with a lower span of 30 mm, an upper span of 10 mm, and a crosshead speed of 0.5 mm / min. The average value of 10 test pieces is taken as the four-point bending strength.

[0064] The Vickers hardness of the tempered glass tends to be higher after chemical tempering than before tempering. This is thought to be because compressive stress is generated in the crystals due to ion exchange between small ions in the crystals and large ions in the molten salt.

[0065] The present tempered glass has a Vickers hardness of preferably at least 720, more preferably at least 740, and even more preferably at least 780. The present tempered glass usually has a Vickers hardness of 950 or less.

[0066] In general, the glass transition point of crystallized glass is higher than that of amorphous glass having the same glass composition. In order to suppress stress relaxation during chemical strengthening treatment, the glass transition point of the crystallized glass is preferably 500°C or higher, more preferably 530°C or higher, even more preferably 550°C or higher, and particularly preferably 570°C or higher. In order to heat the crystallized glass and perform bending processing, etc., the glass transition point of the crystallized glass is preferably 850°C or lower, more preferably 800°C or lower, even more preferably 750°C or lower, and particularly preferably 700°C or lower.

[0067] The difference ΔTg between the glass transition point of the present crystallized glass and that of an amorphous glass having the same glass composition is preferably 200° C. or less, more preferably 195° C. or less, and even more preferably 190° C. or less. Crystallized glass with a small ΔTg is easy to be heated and bent.

[0068] The visible light transmittance, haze value and high frequency characteristics of the present tempered glass are similar to those of the present crystallized glass, and therefore a description thereof will be omitted.

[0069] The tempered glass has a composition generally similar to that of the crystallized glass before tempering, except when it has been subjected to an extreme ion exchange treatment. In particular, the composition of the deepest part from the glass surface is the same as that of the crystallized glass before tempering, except when it has been subjected to an extreme ion exchange treatment.

[0070] <Amorphous glass> The amorphous glass according to the present invention is SiO 2 45-70%, Al 2 O 3 1 to 15%, Li 2 O 10-25%, P 2 O 5 0-12%, ZrO 2 0-15%, Na 2 O 0-10%, K 2 O is 0 to 5%, Y is 2 O 3 It is preferable that the content is 0 to 6%. The glass composition will be described below.

[0071] In this amorphous glass, SiO 2 is a component that forms the network structure of glass. It also increases chemical durability and is a component of lithium metasilicate, which is a precipitated crystal. SiO 2 The content of SiO is preferably 45% or more. 2 The content of SiO is more preferably 48% or more, further preferably 50% or more, particularly preferably 52% or more, and extremely preferably 54% or more. 2 The content is preferably 70% or less, more preferably 68% or less, further preferably 66% or less, and particularly preferably 64% or less.

[0072] Al 2 O 3 Al is an essential component that increases the surface compressive stress due to chemical strengthening. 2 O 3 The content of Al is preferably 1% or more. 2 O 3 The content of Al is more preferably 2% or more, further preferably 4% or more, particularly preferably 6% or more, and extremely preferably 8% or more. On the other hand, in order to prevent the devitrification temperature of the glass from becoming too high, 2 O 3 The content is preferably 15% or less, more preferably 12% or less, even more preferably 10% or less, particularly preferably 8% or less, and most preferably 6% or less.

[0073] Li 2 O is a component that forms surface compressive stress through ion exchange, is a component of lithium metasilicate crystals, and is essential. 2 The content of O is preferably 10% or more, more preferably 14% or more, further preferably 16% or more, and particularly preferably 18% or more. 2 The O content is preferably 25% or less, more preferably 22% or less, and further preferably 20% or less.

[0074] Na 2 O is a component that improves the meltability of glass. 2 O is not essential, but is preferably 0.5% or more, more preferably 1% or more, and particularly preferably 2% or more. 2 If the O content is too high, it becomes difficult to precipitate lithium metasilicate crystals or the chemical strengthening properties decrease, so the O content is preferably 10% or less, more preferably 9% or less, further preferably 8% or less, and particularly preferably 7% or less.

[0075] K 2 O is Na 2 Like O, it is an ingredient that lowers the melting temperature of glass and may be contained. 2 When O is contained, the content is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more. 2 If the O content is too high, the chemical strengthening properties or chemical durability decreases, so the O content is preferably 5% or less, more preferably 4% or less, further preferably 3% or less, and particularly preferably 2% or less.

[0076] Na 2 O and K 2 Total content of Na and O 2 O+K 2 The O content is preferably 1% or more, and more preferably 2% or more. Also, Li 2 O, Na 2 O and K 2 Total Li2 O+Na 2 O+K 2 O to R 2 O, K 2 O / R 2 O is preferably 0.2 or less since this improves the chemical strengthening properties and chemical durability, more preferably 0.15 or less, and even more preferably 0.10 or less. In addition, R 2 O is 10% or more, preferably 15% or more, and more preferably 20% or more. 2 O is 29% or less, and preferably 26% or less.

[0077] P 2 O 5 is not essential, but has the effect of promoting phase separation of glass and accelerating crystallization, and may be contained. 2 O 5 When P is contained, the content is preferably 0.5% or more, more preferably 2% or more, further preferably 4% or more, particularly preferably 5% or more, and extremely preferably 6% or more. 2 O 5 If the content is too high, phase separation occurs easily when melted, and acid resistance is significantly reduced. 2 O 5 The content is preferably 12% or less, more preferably 10% or less, further preferably 8% or less, and particularly preferably 7% or less.

[0078] ZrO 2 is a component that can form crystal nuclei during crystallization treatment and may be contained. 2 The content of ZrO is preferably 1% or more, more preferably 2% or more, further preferably 4% or more, particularly preferably 6% or more, and most preferably 7% or more. On the other hand, in order to suppress devitrification during melting, 2 The content is preferably 15% or less, more preferably 14% or less, further preferably 12% or less, and particularly preferably 11% or less. Also, Li 2 O, Na 2 O and K 2 Total Li 2O+Na 2 O+K 2 O to R 2 O, ZrO 2 / R 2 In order to increase the chemical durability, O is preferably 0.10 or more, and more preferably 0.30 or more. In order to increase the transparency after crystallization, ZrO 2 / R 2 O is preferably 0.80 or less, and more preferably 0.60 or less.

[0079] TiO 2 is a component that can form crystal nuclei during crystallization treatment and may be contained. 2 is not essential, but if it is contained, it is preferably 0.5% or more, more preferably 1% or more, further preferably 2% or more, particularly preferably 3% or more, and most preferably 4% or more. On the other hand, in order to suppress devitrification during melting, TiO 2 The content is preferably 10% or less, more preferably 8% or less, and even more preferably 6% or less.

[0080] SnO 2 SnO has the effect of promoting the formation of crystal nuclei and may be contained. 2 is not essential, but when contained, it is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more. On the other hand, in order to suppress devitrification during melting, SnO 2 The content is preferably 6% or less, more preferably 5% or less, further preferably 4% or less, and particularly preferably 3% or less.

[0081] Y 2 O 3 Y is a component that prevents chemically strengthened glass from scattering when broken, and may be included. 2 O 3 The content of Y is preferably 1% or more, more preferably 1.5% or more, further preferably 2% or more, particularly preferably 2.5% or more, and extremely preferably 3% or more. 2 O 3The content is preferably 5% or less, more preferably 4% or less.

[0082] B 2 O 3 Although not essential, B is a component that improves the chipping resistance and melting property of the glass for chemical strengthening or the chemically strengthened glass, and may be contained. 2 O 3 In the case where B is contained, the content is preferably 0.5% or more, more preferably 1% or more, and further preferably 2% or more in order to improve the melting property. 2 O 3 If the content exceeds 5%, striae may occur during melting, phase separation may occur, and the quality of the glass for chemical strengthening may deteriorate. Therefore, the content is preferably 5% or less. 2 O 3 The content is more preferably 4% or less, further preferably 3% or less, and particularly preferably 2% or less.

[0083] BaO, SrO, MgO, CaO, and ZnO are components that improve the melting property of glass and may be contained. When these components are contained, the total of BaO, SrO, MgO, CaO, and ZnO (BaO+SrO+MgO+CaO+ZnO) is preferably 0.5% or more, more preferably 1% or more, even more preferably 1.5% or more, and particularly preferably 2% or more. On the other hand, since the ion exchange rate decreases, the content of BaO+SrO+MgO+CaO+ZnO is preferably 8% or less, more preferably 6% or less, even more preferably 5% or less, and particularly preferably 4% or less.

[0084] Among these, BaO, SrO, and ZnO may be contained to improve the refractive index of the residual glass and bring it closer to the precipitated crystal phase, thereby improving the light transmittance of the crystallized glass and reducing the haze value. In this case, the total content of BaO+SrO+ZnO is preferably 0.3% or more, more preferably 0.5% or more, even more preferably 0.7% or more, and particularly preferably 1% or more. On the other hand, these components may reduce the ion exchange rate. In order to improve the chemical strengthening properties, BaO+SrO+ZnO is preferably 2.5% or less, more preferably 2% or less, even more preferably 1.7% or less, and particularly preferably 1.5% or less.

[0085] La 2 O 3 , Nb 2 O 5 and Ta 2 O 5 Each of these is a component that makes it difficult for chemically strengthened glass to scatter into fragments when broken, and may be contained in order to increase the refractive index.

[0086] La 2 O 3 , Nb 2 O 5 and Ta 2 O 5 The total content of La 2 O 3 +Nb 2 O 5 +Ta 2 O 5 is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more. In addition, La is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more. 2 O 3 +Nb 2 O 5 +Ta 2 O 5 is preferably 4% or less, more preferably 3% or less, further preferably 2% or less, and particularly preferably 1% or less.

[0087] In addition, the CEO 2 It may contain CeO 2has the effect of oxidizing the glass, and may suppress coloring. 2 When CeO is contained, the content is preferably 0.03% or more, more preferably 0.05% or more, and further preferably 0.07% or more. 2 When using CeO as an oxidizing agent, 2 The content is preferably 1.5% or less, and more preferably 1.0% or less, in order to increase transparency.

[0088] When the tempered glass is used after being colored, a coloring component may be added to the glass within a range that does not impede the achievement of the desired chemical strengthening properties. 3 O 4 , MnO 2 , Fe 2 O 3 , NiO, CuO, Cr 2 O 3 , V 2 O 5 , Bi 2 O 3 , SeO 2 , Er 2 O 3 , Nd 2 O 3 are mentioned as suitable ones.

[0089] The total content of coloring components is preferably within the range of 1% or less. If it is desired to increase the visible light transmittance of the glass, it is preferable that these components are substantially not contained.

[0090] In addition, SO is used as a fining agent when melting glass. 3 , chloride, fluoride, etc. may be appropriately contained. 2 O 3 It is preferable that Sb is not contained. 2 O 3 When it is contained, it is preferably 0.3% or less, more preferably 0.1% or less, and most preferably not contained.

[0091] The glass transition temperature Tg of the present amorphous glass is preferably 390° C. or higher, more preferably 410° C. or higher, and even more preferably 420° C. or higher. If the glass transition temperature Tg is high, stress relaxation during chemical strengthening is unlikely to occur, and high strength is likely to be obtained. On the other hand, if the Tg is too high, it is difficult to mold the glass, so that the glass transition temperature Tg is preferably 650° C. or lower, and more preferably 600° C. or lower.

[0092] The thermal expansion coefficient of this amorphous glass is 90×10 -7 / ℃ or more is preferable, and 100×10 -7 / ℃ or more is more preferable, and 110×10 -7 On the other hand, if the thermal expansion coefficient is too large, the glass is likely to break during molding. -7 / ℃ or less is preferable, and 140×10 -7 / ° C. or less is more preferable. If the difference in thermal expansion coefficient between the amorphous glass and the lithium metasilicate crystal is large, cracks are likely to occur during the crystallization process due to the difference in thermal expansion coefficient.

[0093] The amorphous glass was crushed and the glass transition temperature (Tg DSC The difference (Tc-Tg) between the crystallization peak temperature (Tc) appearing in the lowest temperature range in the DSC curve is preferably 80°C or higher, more preferably 85°C or higher, even more preferably 90°C or higher, and particularly preferably 95°C or higher. If (Tc-Tg) is large, the crystallized glass can be easily reheated and bent or otherwise processed. (Tc-Tg) is preferably 150°C or lower, and more preferably 140°C or lower.

[0094] FIG. 4 is an example of a DSC curve of the amorphous glass according to the present invention. DSC The glass transition temperature (Tg) may not coincide with the glass transition temperature (Tg) obtained from the thermal expansion curve. In addition, since the glass is crushed before measurement, the measurement error is likely to be large. However, in order to evaluate the relationship with the crystallization peak temperature, the Tg obtained by the same DSC measurement is more important than the Tg obtained from the thermal expansion curve. DSC It is appropriate to use

[0095] The Young's modulus of the present amorphous glass is preferably 75 GPa or more, more preferably 80 GPa or more, and even more preferably 85 GPa or more. The Vickers hardness is preferably 500 or more, and more preferably 550 or more.

[0096] <Method of manufacturing chemically strengthened glass> The chemically strengthened glass of the present invention is produced by heat-treating the above-mentioned amorphous glass to obtain crystallized glass, and then chemically strengthening the obtained crystallized glass.

[0097] (Production of amorphous glass) The amorphous glass can be produced, for example, by the following method. Note that the production method described below is an example of the case of producing a plate-shaped chemically strengthened glass.

[0098] Glass raw materials are mixed so as to obtain glass of a desired composition, and are heated and melted in a glass melting furnace. The molten glass is then homogenized by bubbling, stirring, adding a clarifier, etc., and formed into a glass plate of a predetermined thickness by a known forming method, and slowly cooled. Alternatively, the molten glass may be formed into a block shape, slowly cooled, and then cut into a plate shape.

[0099] Examples of forming methods for plate glass include the float method, the press method, the fusion method, and the down-draw method. In particular, when producing a large glass plate, the float method is preferred. In addition, continuous forming methods other than the float method, such as the fusion method and the down-draw method, are also preferred.

[0100] (Crystallization treatment) The amorphous glass obtained by the above procedure is subjected to a heat treatment to obtain crystallized glass.

[0101] The heat treatment is preferably a two-stage heat treatment in which the temperature is raised from room temperature to a first treatment temperature and held for a certain period of time, and then the temperature is held for a certain period of time at a second treatment temperature that is higher than the first treatment temperature.

[0102] In the case of two-stage heat treatment, the first treatment temperature is preferably in a temperature range where the crystal nucleation rate is high in the glass composition, and the second treatment temperature is preferably in a temperature range where the crystal growth rate is high in the glass composition. Also, the holding time at the first treatment temperature is preferably long so that a sufficient number of crystal nuclei are generated. By generating a large number of crystal nuclei, the size of each crystal becomes small, and a highly transparent crystallized glass is obtained.

[0103] The first treatment temperature is, for example, 450° C. to 700° C., and the second treatment temperature is, for example, 600° C. to 800° C., and after being held at the first treatment temperature for 1 hour to 6 hours, the second treatment temperature is held for 1 hour to 6 hours.

[0104] The crystallized glass obtained by the above procedure is ground and polished as necessary to form a crystallized glass plate. When the crystallized glass plate is cut into a predetermined shape and size or chamfered, it is preferable to perform the cutting or chamfering before the chemical strengthening treatment, because a compressive stress layer is formed on the end surface by the subsequent chemical strengthening treatment.

[0105] (Chemical strengthening treatment) Chemical strengthening is a process in which glass is brought into contact with a metal salt, such as by immersing the glass in a molten liquid of a metal salt (e.g., potassium nitrate) containing a metal ion with a large ionic radius (typically Na ion or K ion), thereby replacing the metal ion with a small ionic radius (typically Na ion or Li ion) in the glass with a metal ion with a large ionic radius (typically Na ion or K ion for Li ion, and K ion for Na ion).

[0106] In order to increase the speed of chemical strengthening, it is preferable to use "Li-Na exchange" in which Li ions in the glass are exchanged with Na ions. Also, in order to create a large compressive stress by ion exchange, it is preferable to use "Na-K exchange" in which Na ions in the glass are exchanged with K ions.

[0107] Examples of molten salts for performing chemical strengthening treatment include nitrates, sulfates, carbonates, and chlorides. Examples of nitrates include lithium nitrate, sodium nitrate, potassium nitrate, cesium nitrate, and silver nitrate. Examples of sulfates include lithium sulfate, sodium sulfate, potassium sulfate, cesium sulfate, and silver sulfate. Examples of carbonates include lithium carbonate, sodium carbonate, and potassium carbonate. Examples of chlorides include lithium chloride, sodium chloride, potassium chloride, cesium chloride, and silver chloride. These molten salts may be used alone or in combination.

[0108] The treatment conditions for the chemical strengthening treatment may be appropriately selected, such as time and temperature, taking into consideration the glass composition and the type of molten salt.

[0109] The present tempered glass is preferably obtained, for example, by the following two-stage chemical tempering treatment.

[0110] First, the crystallized glass is immersed for about 0.1 to 10 hours in a metal salt (e.g., sodium nitrate) containing Na ions at about 350 to 500° C. This causes ion exchange between the Li ions in the crystallized glass and the Na ions in the metal salt, forming a compressive stress layer with a surface compressive stress value of 200 MPa or more and a maximum compressive stress layer depth of 80 μm or more.

[0111] Next, the material is immersed in a metal salt (e.g., potassium nitrate) containing K ions at about 350-500°C for about 0.1-10 hours. This generates a large compressive stress in the compressive stress layer formed in the previous treatment, for example, within a depth of about 10 μm. This two-stage treatment makes it easy to obtain a preferable stress profile with a surface compressive stress value of 500 MPa or more.

[0112] On the other hand, if the surface compressive stress value exceeds 1000 MPa, it becomes difficult to increase the DOL while keeping the CT low. The surface compressive stress value is preferably 900 MPa or less, more preferably 700 MPa or less, and further preferably 600 MPa or less.

[0113] After first being immersed in a metal salt containing Na ions, it may be held in air at 350 to 500°C for 1 to 5 hours, and then immersed in a metal salt containing K ions. The holding temperature is preferably 425°C to 475°C, more preferably 440°C to 460°C.

[0114] By holding the glass at high temperatures in air, the sodium ions introduced into the glass from the metal salts during the initial treatment are thermally diffused within the glass, forming a more favorable stress profile, thereby increasing the asphalt drop strength.

[0115] Alternatively, after immersion in the metal salt containing Na ions, instead of holding it in the air, it may be immersed in a metal salt containing Na ions and Li ions (for example, a mixed salt of sodium nitrate and lithium nitrate) at 350 to 500°C for 0.1 to 20 hours.

[0116] By immersing the glass in a metal salt containing Na ions and Li ions, ion exchange occurs between the Na ions in the glass and the Li ions in the metal salt, forming a more favorable stress profile, thereby increasing the asphalt drop strength. In order to increase the asphalt drop strength, the compressive stress value CS50 at a depth of 50 μm is preferably 100 MPa or more, more preferably 140 MPa or more, and even more preferably 160 MPa or more.

[0117] When such a two- or three-stage tempering treatment is performed, the total treatment time is preferably 10 hours or less, more preferably 5 hours or less, and even more preferably 3 hours or less, from the viewpoint of production efficiency. On the other hand, in order to obtain a desired stress profile, the total treatment time must be 0.5 hours or more, and more preferably 1 hour or more.

[0118] The tempered glass is useful not only as a semiconductor support substrate described later, but also as a cover glass for electronic devices such as mobile devices such as mobile phones and smartphones. It is also useful as a cover glass for electronic devices such as televisions, personal computers, and touch panels that are not intended to be portable, elevator walls, and walls (full-surface displays) of buildings such as houses and buildings. It is also useful as building materials such as window glass, table tops, interiors of automobiles and airplanes, and cover glass for these, and for curved housings.

[0119] The tempered glass has good high frequency characteristics and is therefore suitable for use as a cover glass for high frequency communication devices.

[0120] <Semiconductor support substrate> The semiconductor support substrate of the present invention (hereinafter, sometimes referred to as support glass) will be described. The semiconductor support substrate of the present invention is made of the crystallized glass of the present invention. In order to increase the strength, it is more preferable that the semiconductor support substrate is made of the tempered glass of the present invention.

[0121] The present crystallized glass or the present tempered glass has a large thermal expansion coefficient, and is therefore suitable for a support substrate for a fan-out type package. In fan-out type packaging, packages with various average thermal expansion coefficients are formed depending on the ratio of semiconductor chips to resin components, but in recent years, packages with a large amount of resin components and a high average thermal expansion coefficient are often used because there is a demand for high fluidity of mold resin and reduced filling defects.

[0122] 5(A) and 5(B) are examples of cross-sectional views of a supporting glass to be bonded to a semiconductor substrate. The supporting glass G1 shown in FIG. 5(A) is bonded to a semiconductor substrate 10 via a peeling layer 20 (which may function as a bonding layer) at a temperature of, for example, 200°C to 400°C to obtain a laminated substrate 30 shown in FIG. 5(B). As the semiconductor substrate 10, for example, a full-sized semiconductor wafer, a semiconductor chip, a substrate on which a semiconductor chip is molded in a resin, a wafer on which an element is formed, or the like is used. The peeling layer 20 is, for example, a resin that can withstand a temperature of 200°C to 400°C.

[0123] This support substrate is used by being bonded to a semiconductor substrate. For example, it is used as support glass for fan-out type wafer level packages, support glass for image sensors such as MEMS, CMOS and CIS, in which miniaturization of elements by wafer level packages is effective, support glass with through holes (glass interposer; GIP), and support glass for semiconductor back grinding. This support glass is particularly suitable as support glass for fan-out type wafer level and panel level packages.

[0124] FIG. 6 is a cross-sectional view of an example of a laminated substrate in which the supporting glass is used as a supporting substrate for a fan-out type wafer-level package.

[0125] In the fan-out type wafer level package, for example, at a temperature of 200°C to 400°C, the support glass G2 and the semiconductor substrate 40 are laminated via a release layer 50 (which may function as a bonding layer) such as resin. The semiconductor substrate 40 is further embedded in the resin 60 to obtain a laminated substrate 70. Thereafter, the support glass G2 and the semiconductor substrate 40 embedded in the resin 60 are peeled off by irradiating the release layer 50 with, for example, ultraviolet light or a laser through the support glass G2. The support glass G2 is reusable. The semiconductor substrate 40 embedded in the resin 60 is wired with copper wires or the like. Also, wiring with copper wires or the like may be performed in advance on the release layer. The substrate in which the semiconductor chip is embedded in the resin 60 may be used as the semiconductor substrate.

[0126] Since the supporting substrate has high light transmittance, a visible light laser or an ultraviolet light laser having high energy can be effectively used as the laser for peeling. EXAMPLES

[0127] The present invention will be described below with reference to examples, but the present invention is not limited thereto.

[0128] <Preparation and evaluation of amorphous glass> Glass raw materials were mixed to obtain the glass compositions shown in Tables 1 and 2 in terms of mass% based on oxides, and weighed out to obtain 800 g of glass. The mixed glass raw materials were then placed in a platinum crucible and placed in an electric furnace at 1600°C to melt for about 5 hours, degassed, and homogenized.

[0129] The obtained molten glass was poured into a mold and held at the glass transition temperature for 1 hour, and then cooled to room temperature at a rate of 0.5°C / min to obtain a glass block. Using a portion of the obtained block, the glass transition temperature, thermal expansion coefficient, specific gravity, Young's modulus, refractive index, and Vickers hardness of the amorphous glass were evaluated, and the results are shown in Tables 1 and 2. Blanks in the tables indicate that no evaluation was performed.

[0130] G1 to G22 and G26 to G33 are examples of amorphous glasses according to the present invention, and G23 to 25 and 34 are comparative examples. Note that G34 underwent phase separation during the melting process and could not be evaluated.

[0131] (glass transition temperature, thermal expansion coefficient) Based on JIS R1618:2002, a thermal expansion curve was obtained using a thermal dilatometer (TD5000SA manufactured by Bruker AXS) at a heating rate of 10°C / min, and the glass transition point Tg [unit: °C] and the thermal expansion coefficient were calculated from the obtained thermal expansion curve.

[0132] (specific gravity) Measured by Archimedes method

[0133] (Young's Modulus) Measured by ultrasonic method.

[0134] (Vickers hardness) The hardness was measured by pressing an indenter with a load of 100 gf for 15 seconds using a Shimadzu micro Vickers hardness tester (Shimadzu Corporation; HMV-2).

[0135] (DSC measurement) The glass was crushed using an agate mortar, and about 80 mg of the powder was placed in a platinum cell. The temperature was raised from room temperature to 1100°C at a heating rate of 10 / min. DSC was measured using a differential scanning calorimeter (Bruker DSC3300SA) to determine the glass transition point Tg DSC The first crystallization peak temperature Tc and the temperature difference Tc-Tg were determined. Figure 4 shows the measurement results for G13.

[0136] (High frequency characteristics) The obtained glass block was processed into a plate with a thickness of 0.5 mm, and the relative dielectric constant ε and dielectric loss tangent tan δ at 10 GHz were measured by the splip post dielectric resonance method (SPDR method) using a network analyzer. The results are shown in Table 1. The same measurements were also made after the crystallization treatment described below. The measurement results after the crystallization treatment are shown in Table 3.

[0137] [Table 1]

[0138] [Table 2]

[0139] <Crystallization treatment and evaluation of crystallized glass> The obtained glass block was processed to 50 mm x 50 mm x 1.5 mm, and then heat-treated under the conditions shown in Tables 3 and 4 to obtain crystallized glass. In the crystallization condition column of the table, the upper row indicates the nucleation treatment conditions, and the lower row indicates the crystal growth treatment conditions. For example, if the upper row indicates 550°C-2h and the lower row indicates 730°C-2h, the sample was held at 550°C for 2 hours, and then held at 730°C for 2 hours. GC1 to GC17, GC19, and GC23 to GC35 are examples, and GC18 and GC20 to GC22 are comparative examples.

[0140] The obtained crystallized glass was processed and mirror-polished to obtain a crystallized glass plate with a thickness t of 0.7 mm. A rod-shaped sample was also prepared to measure the thermal expansion coefficient. A portion of the remaining crystallized glass was crushed and used to analyze the precipitated crystals. The evaluation results of the crystallized glass are shown in Tables 3 to 5. Blanks indicate that no evaluation was performed.

[0141] (visible light transmittance, Y value, dominant wavelength λd, excitation purity Pe) The transmittance of the crystallized glass plate at wavelengths of 380 to 780 nm was measured using a spectrophotometer (PerkinElmer; LAMBDA950) equipped with an integrating sphere unit (150 mm InGaAs Int. Specter) as a detector, and the arithmetic mean value was taken as the average transmittance [unit: %] to be the visible light transmittance.

[0142] In addition, the tristimulus values ​​X, Y, and Z of the object in the XYZ color system were calculated as the object color under light source C from the measured transmittance value, and the dominant wavelength λd and excitation purity Pe were calculated based on these.

[0143] (Haze value) The haze value (unit: %) was measured using a haze meter (HZ-V3 manufactured by Suga Test Instruments) under light source C.

[0144] (X-ray diffraction: precipitated crystals and crystallization rate) The precipitated crystals were identified by powder X-ray diffraction under the following conditions. The crystallization rate was calculated from the obtained diffraction intensity by the Rietveld method. Measurement equipment: Rigaku SmartLab X-ray used: CuKα ray Measurement range: 2θ=10°~80° Speed: 10° / min Step: 0.02°

[0145] The detected crystals are shown in the crystal type column of Tables 3 to 4. In the tables, LS stands for lithium metasilicate, LD stands for lithium disilicate, βSP stands for β-spodumene, LP stands for lithium phosphate, and spinel stands for spinel. The crystallization ratio is the sum of the crystallization ratios calculated by the Rietveld method for each crystal listed in Tables 3 to 5.

[0146] (Crystal Size) The crystallized glass GC1 was crushed in an agate mortar and then spread on a hydrophilized collodion film, and the ultra-thin area was observed with a transmission electron microscope (JEM-2010F, manufactured by JEOL Ltd.) to determine the average grain size (unit: nm) of the precipitated crystals. The TEM image is shown in Figure 7.

[0147] (glass transition temperature, thermal expansion coefficient, specific gravity, Young's modulus, Vickers hardness) The measurements were performed in the same manner as for the glass before crystallization. The difference in Tg between before and after crystallization was also calculated.

[0148] (Refractive Index) The sample was mirror-polished to a size of 15 mm x 15 mm x 0.7 mm, and the refractive index was measured by the V-block method using a precision refractometer KPR-2000 (manufactured by Shimadzu Devices Manufacturing Co., Ltd.).

[0149] [Table 3]

[0150] [Table 4]

[0151] [Table 5]

[0152] GC18, in which lithium disilicate crystals precipitated in addition to lithium metasilicate crystals, contained crystals with large particle sizes, had a high haze value, and had poor appearance.GC20 and GC21, in which β-spodumene precipitated, had glass transition points after crystallization exceeding 800°C, and were therefore poor in bending workability.

[0153] <Chemical strengthening treatment and evaluation of strengthened glass> GC1 to GC16, GC19, GC22 and uncrystallized G1 were subjected to a two-stage chemical strengthening treatment of immersion in sodium nitrate at 450°C for three hours and then in potassium nitrate at 450°C for one hour to obtain tempered glasses SG1 to SG19. SG1 to SG16 are examples and SG17 to SG19 are comparative examples.

[0154] (Stress Profile) The stress values ​​were measured using a surface stress meter FSM-6000 manufactured by Orihara Seisakusho Co., Ltd. and a measuring instrument SLP-2000 manufactured by Orihara Seisakusho Co., Ltd. that applies scattered light photoelasticity, and the compressive stress value CS of the glass surface was obtained. 0 [Unit: MPa], compressive stress value CS at a depth of 50 μm 50 The results of reading the stress [unit: MPa] and the depth DOL [unit: μm] at which the compressive stress value becomes zero are shown in Tables 6 to 7.

[0155] Moreover, the stress profile of SG13 is shown in Figure 1.

[0156] [Table 6]

[0157] [Table 7]

[0158] SG17, which is made by chemically strengthening non-crystallized glass, exhibited a low CS due to stress relaxation during the strengthening process. 0 is small. 2 SG18, which is a chemically strengthened version of GC19, a glass-ceramic material with a high O content, is also a CS. 0is small. Also, Li 2 SG19, which is obtained by chemically strengthening the comparative glass-ceramics GC22 that does not contain O, has a small DOL and is difficult to obtain sufficient strength. It is clear that this glass-ceramics can obtain high strength by chemical strengthening treatment.

[0159] Although the present invention has been described in detail with reference to specific embodiments, it is apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2019-021896) filed on February 8, 2019, and is incorporated by reference in its entirety. In addition, all references cited herein are incorporated in their entirety.

Claims

1. A chemically strengthened glass having a compressive stress layer on a surface thereof, The visible light transmittance converted to a thickness of 0.7 mm is 85% or more, and the haze value converted to a thickness of 0.7 mm is 0.5% or less, The compressive stress layer depth is 80 μm or more, The compressive stress value on the surface is 490 MPa or more, The compressive stress value at a depth of 50 μm from the surface is 100 MPa or more, In terms of mass% based on oxides, SiO ２ More than 45% A ２ O ３ is 1% or more, Li ２ O is 10% or more, ZrO ２ 1 to 15%, P ２ O ５ 0.5 to 12%, Na ２ A chemically strengthened glass is a crystallized glass containing 0.1 to 10% O.

2. A ２ O ３ is 15% or less, Li ２ 2. The chemically strengthened glass according to claim 1, which is glass-ceramic having an O content of 25% or less.

3. ZrO ２ / R ２ 2. The chemically strengthened glass according to claim 1, which is glass-ceramic, in which O is 0.37 to 0.

8.

4. The dominant wavelength λd is 580 nm or less, 2. The chemically strengthened glass according to claim 1, which is glass-ceramic having an excitation purity Pe of 1.0 or less.

5. 2. The chemically strengthened glass according to claim 1, which is the glass-ceramic according to claim 1, containing lithium metasilicate crystals.

6. 2. A chemically strengthened glass, which is the glass-ceramic according to claim 1, containing lithium phosphate crystals.

7. 2. The chemically strengthened glass according to claim 1, which contains lithium disilicate crystals and has a crystal diameter of 45 nm or less calculated from the width of its X-ray diffraction peak according to Scherrer's formula.

8. The average thermal expansion coefficient at 50°C to 350°C is 90 x 10 －７ / ℃~140×10 －７ The chemically strengthened glass, which is the glass-ceramic according to claim 1, wherein the temperature is 100° C. / ° C.

9. 2. The chemically strengthened glass according to claim 1, which is a crystallized glass having a Vickers hardness of 600 or more.

10. The compressive stress value at a depth of 50 μm from the surface is 195 MPa or less; A chemically strengthened glass which is the glass-ceramic according to claim 1.

11. An electronic device comprising the chemically strengthened glass, which is the glass-ceramic according to claim 1.

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