Glass and method for manufacturing glass
Glass contains, in mol percentage on an oxide basis, SiO 2 : 35% to 60%, B 2 O 3 : 0.8% to 8%, Al 2 O 3 : 6% to 21%, and MgO: 17% to 44%. Additionally, (MgO/Al 2 O 3 )≥1 is satisfied, a measured Madelung constant m calculated by an expression (1A) is equal to or larger than 1.05, and a thermal expansion factor as a ratio of a measured value α of a linear thermal expansion coefficient to a calculated value α cal of a linear thermal expansion coefficient calculated from composition is equal to or smaller than 0.7. Herein, E is a measured value of a Young's modulus of the glass, V p is an average atomic packing factor of the glass, and G t is average bond dissociation energy of the glass.
1 . Glass A glass containing:
SiO 2 : 35% to 60%;
B 2 O 3 : 0.8% to 8%;
Al 2 O 3 : 6% to 21%; and
MgO: 17% to 44% and
TiO 2 : 0.3% to 8%,
in mol percentage on an oxide basis, wherein
(MgO/Al 2 O 3 )≥1 is satisfied,
a measured Madelung constant m calculated by an expression (1A) is equal to or larger than 1.05,
m
=
E
/
(
2
·
V
p
·
G
t
)
(
1
A
)
where E is a measured value of a Young's modulus (GPa) of the glass, V p is an average atomic packing factor of the glass, and G, is average bond dissociation energy of the glass, and
a thermal expansion factor as a ratio of a measured value α (ppm/K) of a linear thermal expansion coefficient to a calculated value α cal (ppm/K) of the linear thermal expansion coefficient calculated from composition is equal to or smaller than 0.7.
2 . The glass according to claim 1 , wherein
assuming that a thermal expansion parameter α pi of an oxide is a value calculated by the following expression (2A), a calculated value α cal of a linear thermal expansion coefficient of glass containing only a modified oxide component of a monovalent element contained in the glass is a value calculated by the following expression (2B), a calculated value α cal 2 of a linear thermal expansion coefficient of glass containing only a modified oxide component of a divalent element contained in the glass is a value calculated by the following expression (2C), and a calculated value α cal 3 of a linear thermal expansion coefficient of glass containing only a modified oxide component of a trivalent element contained in the glass is a value calculated by the following expression (2D),
the calculated value deal is calculated by the following expression (2E),
α
p
i
=
{
ni
/
(
ni
-
1
)
}
·
(
Z
+
i
·
Z
-
i
/
r
e
q
i
)
-
1
(
2
A
)
α
ca
l
1
=
(
290
·
α
p
-
8
9
.6
)
/
10
(
2
B
)
α
ca
l
2
=
(
300
·
α
p
-
4
9
.1
)
/
10
(
2
C
)
α
ca
l
3
=
(
848
·
α
p
-
2
34
)
/
10
(
2
D
)
α
ca
l
=
(
M
1
·
α
ca
l
1
+
M
2
·
α
ca
l
2
+
M
3
·
α
ca
l
3
)
/
{
10
·
(
M
1
+
M
2
+
M
3
)
(
2
E
)
where ni is a Born exponent, Z +i is a cationic charge of the oxide, Z −i is an anionic charge of the oxide, r eqi is an equilibrium value of an average distance between a pair of ions of the oxide at a temperature 0 (K), α p in the expressions (2B), (2C), and (2D) is a numerical value obtained by adding up values that are obtained by multiplying the expression (2A) by a cation ratio of each oxide, M1 is a cation ratio (%) of a content of a modified oxide of the monovalent element, M2 is a cation ratio (%) of a content of a modified oxide of the divalent element, and M3 is a cation ratio (%) of a content of a modified oxide of the trivalent element.
3 . The glass according to claim 1 , wherein the measured Madelung constant m is equal to or smaller than 1.35.
4 . The glass according to claim 1 , wherein the thermal expansion factor is equal to or larger than 0.45.
5 . The glass according to claim 1 , containing:
CaO: 0% to 8%,
TiO 2 : 0.3% to 8%,
ZrO 2 : 0% to 8%,
Na 2 O 3 : 0% to 7%, and
K 2 O: 0% to 6%,
in mol percentage on an oxide basis.
6 . The glass according to claim 1 , containing:
SiO 2 : 35% to 52%,
Al 2 O 3 : 9.6% to 20%,
MgO: 24% to 44%,
B 2 O 3 : 0.8% to 4.5%, and
TiO 2 : 0.3% to 5%,
in mol percentage on an oxide basis.
7 . The glass according to claim 1 , wherein the glass is amorphous glass.
8 . The glass according to claim 1 , wherein the glass is a support glass substrate for manufacturing at least one of a Fan Out Wafer Level Package and a Fan Out Panel Level Package.
9 . A method for manufacturing the glass of claim 1 , the method comprising:
shaping glass, the glass containing:
SiO 2 : 35% to 60%,
B 2 O 3 : 0.8% to 8%,
Al 2 O 3 : 6% to 21%, and
MgO: 17% to 44%, and
TiO 2 : 0.3% to 8%,
in mol percentage on an oxide basis;
holding the shaped glass at a temperature higher than a glass transition point Tg by a temperature equal to or higher than 0° C. and equal to or lower than 100° C. for a time longer than 0 hours and equal to or shorter than 10 hours; and
cooling the glass so that a temperature lowering speed is equal to or higher than 0.5° C./min and equal to or lower than 100° C./min.