Cover glass for solid-state imaging element package
View Patent ↗A cover glass, containing, by mole percentage: 15 to 40% of P 2 O 5 ; 15 to 30% of Al 2 O 3 ; 0 to 15% of SiO 2 ; 0 to 20% of B 2 O 3 ; 0 to 10% of Li 2 O; 0 to less than 20% of Na 2 O; 0 to less than 20% of K 2 O, provided that Li 2 O+Na 2 O+K 2 O is in a range from 15 to less than 20%; and from 1 to 35% of MgO+CaO+SrO+ZnO. The cover glass being suitable for at least one selected from the group consisting of a solid-state imaging element package and an air-tight sealing of a resin package, and having a sufficient strength not to undergo breakage even when subjected to external force.
1. A cover glass, comprising, by mole percentage:
P 2 O 5 : 15 to 40%;
Al 2 O 3 : 15 to 30%;
SiO 2 : 0 to 15%;
B 2 O 3 : 0 to 20%;
Li 2 O: 0 to 10%;
Na 2 O: 0 to less than 20%;
K 2 O: 0 to less than 20%, provided that
Li 2 O+Na 2 O+K 2 O: 15 to less than 20%; and
MgO+CaO+SrO+ZnO: 1 to 35%.
2. The cover glass claim 1 , having an average thermal expansion coefficient of from 85 to 110×10 −7 K −1 within a range of from 50 to 250° C.
3. The cover glass of claim 1 , containing substantially no CuO.
4. The cover glass of claim 1 , comprising:
P 2 O 5 : 25 to 35 mol %.
5. The cover glass of claim 1 , comprising:
Al 2 O 3 : 17 to 27 mol %.
6. The cover glass of claim 1 , comprising:
Al 2 O 3 : 20 to 27 mol %.
7. The cover glass of claim 1 , comprising:
SiO 2 : 0 to 12 mol %.
8. The cover glass of claim 1 , comprising:
B 2 O 3 : 0 to 15 mol %.
9. The cover glass of claim 1 , comprising:
Li 2 O: 0 to 7 mol %.
10. The cover glass of claim 1 , comprising:
Na 2 O: 0 to less than 15%.
11. The cover glass of claim 1 , comprising:
K 2 O: 0 to less than 15%.
12. The cover glass of claim 1 , comprising:
Li 2 O: 0 to 7 mol %;
Na 2 O: 0 to less than 15%; and
K 2 O: 0 to less than 15%, provided that
Li 2 O+Na 2 O+K 2 O: 17 to less than 19%.
13. The cover glass of claim 1 , comprising:
MgO+CaO+SrO+ZnO: 10 to 25%.
14. The cover glass of claim 1 , further comprising:
at least one selected from the group consisting of La 2 O 3 , Y 2 O 3 , Gd 2 O 3 , Ta 2 O 5 , Yb 2 O 3 , TiO 2 .
15. The cover glass of claim 1 , containing substantially no BaO.
16. The cover glass of claim 1 , containing substantially no ZrO 2 .
17. The cover glass of claim 1 , comprising:
P 2 O 5 : 25 to 35 mol %;
Al 2 O 3 : 17 to 27 mol %;
SiO 2 : 0 to 12 mol %;
B 2 O 3 : 0 to 15 mol %;
Li 2 O: 0 to 7 mol %;
Na 2 O: 0 to less than 15%;
K 2 O: 0 to less than 15%, provided that
Li 2 O+Na 2 O+K 2 O: 17 to less than 19%; and
MgO+CaO+SrO+ZnO: 10 to 25%.
18. The cover glass of claim 17 , having an average thermal expansion coefficient of from 85 to 110×10 −7 K −1 within a range of from 50 to 250° C.
19. The cover glass of claim 17 , containing substantially no CuO.
20. The cover glass of claim 1 , being suitable for a solid-state imaging element package which is to be attached to a resin package.