Glass ceramics, chemically strengthened glass, and semiconductor substrate

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.

1 . 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
 comprising, in mass % on an oxide basis:   45-70% of SiO 2 ;   1-15% of Al 2 O 3 ; and   10-25% of Li 2 O.   
     
     
         2 . The glass ceramic according to  claim 1 , having a content of K 2 O of 5% or less in mass % on an oxide basis. 
     
     
         3 . The glass ceramic according to  claim 1 , comprising lithium metasilicate crystals. 
     
     
         4 . The glass ceramic according to  claim 1 , comprising lithiumphosphate crystals. 
     
     
         5 . The glass ceramic according to  claim 3 , wherein, in a case where lithium disilicate crystals are contained, the lithium disilicate crystals have a crystal size of 45 nm or less, the crystal size being determined using Scherrer equation from a width of an X-ray diffraction peak of the lithium disilicate crystals. 
     
     
         6 . The glass ceramic according to  claim 1 , having a glass transition point that differs by 200° C. or less from a glass transition point of an amorphous glass having the same glass composition as a glass composition of the glass ceramic. 
     
     
         7 . The glass ceramic according to  claim 1 , wherein the haze value is 0.4% or less in terms of a thickness of 0.7 mm. 
     
     
         8 . A semiconductor-supporting substrate comprising the glass ceramic according to  claim 1 . 
     
     
         9 . A chemically strengthened glass having a compressive stress layer in a surface thereof, the chemically strengthened glass being a glass ceramic that has 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,
 has a surface compressive stress value of 500 MPa or more and a depth of the compressive stress layer of 80 μm or more, and   comprises, in mass % on an oxide basis:   45-70% of SiO 2 ;   1-15% of Al 2 O 3 ; and   10-25% of Li 2 O.   
     
     
         10 . The chemically strengthened glass according to  claim 9 , comprising lithium metasilicate crystals. 
     
     
         11 . The chemically strengthened glass according to  claim 10 , comprising lithiumphosphate crystals. 
     
     
         12 . The chemically strengthened glass according to  claim 9 , having a compressive stress value of 100 MPa or more at a depth of 50 m from the surface. 
     
     
         13 . The chemically strengthened glass according to  claim 9 , having an average thermal expansion coefficient at 50° C.-350° C. of 90×10 −7 /° C.-140×10 −7 /° C. 
     
     
         14 . The chemically strengthened glass according to  claim 9 , having a Vickers hardness of 600 or more. 
     
     
         15 . A semiconductor-supporting substrate comprising the chemically strengthened glass according to  claim 9 . 
     
     
         16 . An electronic appliance comprising the chemically strengthened glass according to  claim 9 .