Title:
WINDOW GLASS FOR SEMICONDUCTOR PACKAGE AND ITS PRODUCTION
Document Type and Number:
Japanese Patent JP3589421
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To suppress the occurrence of the soft error of a solid-state image pickup element and to improve the picture quality by keeping the contents of U and Th below a specified value.
SOLUTION: The window glass for a semiconductor package contains ≤5 ppb of U and Th. As a result of such extremely low contents of U and Th, the α-ray emission becomes as low as ≤0.0015 C/cm2.h, and the soft error rate is drastically decreased when used in a solid-state image pickup element. Borosilicate glass, etc., are exemplified as the material for the window glass. The borosilicate glass contains, by weight, 50-78% SiO2, 5-25% B2O3, 0-8% Al2O3, 0-5% Li2O, 0-18% Na2O and 0-20% K2O (where Li2O+Na2O+K2O =5-20%), their total content is ≥80%, and the thermal expansion coefficient is preferably controlled to 45-75×10-7K-1.
Inventors:
Koji Sagara
Application Number:
JP18530999A
Publication Date:
November 17, 2004
Filing Date:
April 28, 1995
Export Citation:
Assignee:
HOYA CORPORATION
International Classes:
H01L31/02; C03C3/091; C03C3/17; C03C4/00; H01L27/14; (IPC1-7): C03C4/00; C03C3/091; C03C3/17; H01L27/14; H01L31/02
Domestic Patent References:
| JP5343659A | ||||
| JP725640A |
Attorney, Agent or Firm:
Shizuo Nakamura