Low temperature sealing composition
AssigneeNippon Electric Glass Co., Ltd.
InventorsIchiro Matsuura, Fumio Yamaguchi
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Abstract
A sealing composition suitable for sealing alumina packages for integrated circuits at a temperature below about 450.degree. C. for a short time of about 10 minutes. The composition is a mixture of 50-80 wt. % vitreous solder glass powder of PbO-B.sub.2 O.sub.3 system having a deformation point of 350.degree. C. or less, 1-35 wt. % first ceramic powder and 1-45 wt. % second ceramic powder. The total amount of the first and second ceramic powders is 20-50 wt. %. The first ceramic comprises 68-75 wt. % ZnO, 23-28 wt. % SiO.sub.2 and 0-8 wt. % Al.sub.2 O.sub.3, and the second ceramic comprises 98-99.9 wt. % SnO.sub.2 and 0.1-2 wt. % ZnO.
Claims5
A low temperature sealing composition for a seal of high mechanical strength between two alumina ceramic parts to form a sealed package having a shearing strength of at least 310 kg, the sealing composition having a sealing temperature of no more than 450.degree. C. and consisting essentially of a mixture of 50-80 wt.% of a vitreous solder glass powder of PbO-B.sub.2 O.sub.3 system having a deformation point of 350.degree. C. or less, 1-35 wt.% of a first ceramic powder and 1-45 wt.% of a second ceramic powder, the total amount of said first and second ceramic powders being 20-50 wt.%, said first ceramic powder consisting of 68-75 wt.% ZnO, 23-28 wt.% SiO.sub.2 and up to 8 wt.% Al.sub.2 O.sub.3, and said second ceramic powder consisting of 98-99.9 wt.% SnO.sub.2 and 0.1-2 wt.% ZnO.
Dependencies are inferred from the claim text.