Abstract: An alkali-free glass substrate which is a glass substrate includes, as represented by molar percentage based on oxides, 0.1% to 10% of ZnO. The alkali-free glass substrate has an average coefficient of thermal expansion ?50/100 at 50 to 100° C. of from 2.70 ppm/° C. to 3.20 ppm/° C., an average coefficient of thermal expansion ?200/300 at 200 to 300° C. of from 3.45 ppm/° C. to 3.95 ppm/° C., and a value ?200/300/?50/100 obtained by dividing the average coefficient of thermal expansion ?200/300 at 200 to 300° C. by the average coefficient of thermal expansion ?50/100 at 50 to 100° C. of from 1.20 to 1.30.

Abstract: Provided is a glass substrate with which it is possible to reduce dielectric loss in high-frequency signals, and which also has excellent thermal shock resistance. This invention satisfies the relation {Young's modulus (GPa)×average thermal expansion coefficient (ppm/° C.) at 50-350° C.}?300 (GPa·ppm/° C.), wherein the relative dielectric constant at 20° C. and 35 GHz does not exceed 10, and the dielectric dissipation factor at 20° C. and 35 GHz does not exceed 0.006.

Abstract: An alkali-free glass includes, as represented by mole percentage based on oxides, SiO2: 57 to 70%, Al2O3: 5 to 15%, B2O3: 15 to 24%, MgO: 0.2 to 10%, CaO: 0.1 to 7%, SrO: 0.1 to 2.5%, BaO: 0 to 10%, and ZnO: 0 to 0.1%, or includes, as represented by mole percentage based on oxides, SiO2: 57 to 70%, Al2O3: 5 to 15%, B2O3: 15 to 24%, MgO: 0.1 to 10%, CaO: 0.1 to 10%, SrO: 0.1 to 10%, BaO: 0.1 to 10%, and ZnO: 0 to 0.1%. Formula (A) is [Al2O3]/[B2O3], and a value of the formula (A) is larger than 0.35 and 1.4 or smaller.

Abstract: A glass plate has a dielectric dissipation factor at 10 GHz of tan ?A and a glass transition temperature of Tg° C. The glass plate satisfies (tan ?100?tan ?A)?0.0004, where tan ?100 is a dielectric dissipation factor of the glass plate at 10 GHz after having been heated to (Tg+50)° C. and then cooled to (Tg?150)° C. at 100° C./min.

Abstract: A glass substrate contains, as a glass matrix composition as represented by mole percentage based on oxides, SiO2: 58-75%, Al2O3: 4.5-16%, B2O3: 0-6%, MgO: 0-6%, CaO: 0-6%, SrO: 5-20%, BaO: 5-20%, and MgO+CaO+SrO+BaO:15-40%. The glass substrate has an alkali metal oxide content of 0-0.1% as represented by mole percentage based on oxides. The glass substrate has an average coefficient of thermal expansion ? of 56-90 (×10?7/° C.) at 50° C.-350° C.

Abstract: An alkali-free glass includes, in mol % in terms of oxides: SiO2: 63-75%; Al2O3:10-16%; B2O3: larger than 0.5% and 5% or smaller; MgO: 0.1-15%; CaO: 0.1-12%; SrO: 0-8%; and BaO: 0-6%. [MgO]/[CaO] is larger than 1.5. A value of Formula (A) is 82.5 or larger. A value of Formula (B) is 690 or larger and 800 or smaller. A value of Formula (C) is 100 or smaller. A value of Formula (D) is 20 or smaller. The alkali-free glass has a Young's modulus of 83 GPa or larger and a surface devitrification viscosity ?c of 104.2 dPa·s or higher.

Abstract: An alkali-free glass includes, in mol % in terms of oxides: SiO2: 63-75%; Al2O3: 10-16%; B2O3: 0-5%; MgO: 0.1-15%; CaO: 0.1-12%; SrO: 0-8%; and BaO: 0-6%. [MgO]/[CaO] is 1.5 or smaller. A value of Formula (A) is 82.5 or larger. A value of Formula (B) is 690 or larger and 800 or smaller. A value of Formula (C) is 100 or smaller. A value of Formula (D) is 20 or smaller. The alkali-free glass has a Young's modulus of 83 GPa or larger and a surface devitrification viscosity ?c of 104.2 dPa·s or higher.

Abstract: An alkali-free glass includes, in mol % in terms of oxides: SiO2: 63-69%; Al2O3: 8-13%; B2O3: 0.5-4%; MgO: 8-15%; CaO: 4-12%; SrO: 0-4.5%; and BaO: 0-1%. [MgO]/[CaO] is 0.67 to 3.75. A value of Formula (A) is 84 or larger. A value of Formula (B) is 715 or smaller. A value of Formula (C) is 200 or smaller. A value of Formula (D) is 15 or smaller.

Abstract: A glass substrate is laminated with a substrate containing silicon to thereby form a laminated substrate. The glass substrate has a concave surface and a convex surface and has one or more marks that distinguish between the concave surface and the convex surface.

Abstract: A glass substrate contains, as a glass matrix composition as represented by mole percentage based on oxides, SiO2: 58-75%, Al2O3: 4.5-16%, B2O3: 0-6%, MgO: 0-6%, CaO: 0-6%, SrO: 5-20%, BaO: 5-20%, and MgO+CaO+SrO+BaO: 15-40%. The glass substrate has an alkali metal oxide content of 0-0.1% as represented by mole percentage based on oxides. The glass substrate has an average coefficient of thermal expansion ? of 56-90 (×10?7/° C.) at 50° C.-350° C.

Abstract: The present invention relates to a glass ceramic having a visible-light transmittance of 85% or more in terms of a thickness of 0.7 mm, and a haze value of 1.0% or less in terms of a thickness of 0.7 mm, and including, in mass % on an oxide basis: 45-70% of SiO2; 1-15% of Al2O3; and 10-25% of Li2O.

Abstract: The present invention provides a glass substrate in which in a step of sticking a glass substrate and a silicon-containing substrate to each other, bubbles hardly intrude therebetween. The present invention relates to a glass substrate for forming a laminated substrate by lamination with a silicon-containing substrate, having a warpage of 2 ?m to 300 ?m, and an inclination angle due to the warpage of 0.0004° to 0.12°.

Abstract: A glass substrate is laminated with a substrate containing silicon to thereby form a laminated substrate. The glass substrate has a concave surface and a convex surface and has one or more marks that distinguish between the concave surface and the convex surface.

Abstract: The present invention provides a glass substrate in which in a step of sticking a glass substrate and a silicon-containing substrate to each other, bubbles hardly intrude therebetween. The present invention relates to a glass substrate for forming a laminated substrate by lamination with a silicon-containing substrate, having a warpage of 2 ?m to 300 ?m, and an inclination angle due to the warpage of 0.0004° to 0.12°.

Abstract: A glass substrate for high-frequency devices includes, in terms of molar percentage based on oxides: one or more alkaline-earth metal oxides in a total amount of 0.1 to 13%; Al2O3 and B2O3 in a total amount of 1 to 40%, in which a molar ratio of the contents represented by Al2O3/(Al2,O3+B2O3) is 0 to 0.45; at least one oxide selected from the group consisting of Sc2O3, TiO2, ZnO, Ga2O3, GeO2, Y2O3, ZrO2, Nb2O5, In2O3, TeO2, HfO2, Ta2O5, WO3, Bi2O3, La2O3, Gd2O3, Yb2O3, and Lu2O3, in a total amount of 0.1 to 1.0%; and SiO2 as a main component. The glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

Abstract: To provide an alkali-free glass having a high specific elastic modulus, a suitable strain point, a low density, a not too low thermal expansion coefficient, a good clarity and a good solubility. An alkali-free glass, which comprises, as represented by mol % based on oxides, SiO2: 62 to 70%, Al2O3: 11 to 14%, B2O3: 3 to 6%, MgO: 7 to 10%, CaO: 3 to 9%, SrO: 1 to 5% and BaO: 0 to 1%, wherein [SiO2]+0.7[Al2O3]+1.2[B2O3]+0.5[MgO]+0.4[CaO]?0.25[SrO]?0.88[BaO] is at least 85, [SiO2]+0.45[Al2O3]+0.21[B2O3]?0.042[MgO]+0.042[CaO]+0.15[SrO]+0.38[BaO] is from 72 to 75, 0.4[SiO2]+0.4[Al2O3]+0.25[B2O3]?0.7[MgO]?0.88[CaO]?1.4[SrO]?1.7[BaO] is at most 19, the specific modulus is at least 32 MN·m/kg, the strain point is from 690 to 710° C., the density is at most 2.54 g/cm3, the average thermal expansion coefficient at from 50 to 350° C. is at least 35×10?7/° C., and the temperature T2 at which the glass viscosity reaches 102 dPa·s is from 1,610 to 1,680° C.

Abstract: To provide an alkali-free glass, of which the compaction is low, the strain point is high, and the ultraviolet transmittance is high, and which is easy to melt. An alkali-free glass, which comprises, as represented by mol % based on oxides, SiO2 from 65 to 75, Al2O3 from 9 to 15, B2O3 from 0 to 3, MgO from 0 to 12, CaO from 0 to 8, SrO from 0 to 6, and BaO from 0 to 5, wherein MgO+CaO+SrO+BaO is from 12 to 22, and 4.84[Fe2O3]+5.65[Na2O]+4.03[K2O]+4.55[SnO2] is at most 0.55, and of which the compaction is at most 80 ppm.

Abstract: To provide a glass plate having a high Young's modulus and a high devitrification viscosity. A glass includes, in mol % based on oxides: SiO2 of 30.0 to 50.0%; B2O3 of 10.0 to 30.0%; Al2O3 of 10.0 to 30.0%; Y2O3 of 3.0 to 17.0%; and Gd2O3 of 3.5 to 17.0%, in which (Gd2O3+Y2O3) is from 16.0 to 22.0%, and (Gd2O3/Y2O3) is from 0.15 to 7.0.

Abstract: A glass substrate for a high-frequency device, which contains, in terms of mole percent on the basis of oxides: 40 to 75% of SiO2; 0 to 15% of Al2O3; 13 to 23% of B2O3; 2.5 to 11% of MgO; and 0 to 13% of CaO, and having a total content of alkali metal oxides in the range of 0.001-5%, where at least one main surface of the glass substrate has a surface roughness of 1.5 um or less in terms of arithmetic average roughness Ra. and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

Abstract: A supporting glass substrate has a ratio of a Young's modulus (GPa) to a density (g/cm3) that is 37.0 (GPa·cm3/g) or more and the ratio has a value larger than a ratio calculation value, the ratio calculation value being a ratio of a Young's modulus (GPa) calculated from a composition to a density (g/cm3). The ratio calculation value is represented by the following expression: ?=2·?{(Vi·Gi)/Mi·Xi}, where, in the expression, Vi is a filling parameter of a metal oxide contained in the supporting glass substrate, Gi is a dissociation energy of a metal oxide contained in the supporting glass substrate, Mi is a molecular weight of a metal oxide contained in the supporting glass substrate, and Xi is a molar ratio of a metal oxide contained in the supporting glass substrate.