Glass composition for covering semiconductor element
AssigneeTokyo Shibaura Denki Kabushiki Kaisha
InventorsKazuyoshi Furukawa, Masaru Shimbo, Kiyoshi Fukuda, Katsujirou Tanzawa
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Abstract
A glass composition for covering a semiconductor element. The glass composition has excellent resistance to chemicals and excellent electric characteristics. The glass composition includes 3 to 8% by weight of Al.sub.2 O.sub.3, 35 to 45% by weight of SiO.sub.2, 10 to 30% by weight of ZnO, 5 to 30% by weight of PbO, 1 to 10% by weight of B.sub.2 O.sub.3, and more than 5% but not exceeding 20% by weight of an alkaline earth metal oxide selected from the group consisting of MgO, CaO, SrO and BaO, where the maximum contents of MgO, CaO, SrO and BaO are 7% by weight, 3% by weight, 7% by weight, and 15% by weight, respectively.
Claims4
A glass composition for covering a semiconductor element consisting essentially of 3 to 8% by weight of Al.sub.2 O.sub.3, 35 to 45% by weight of SiO.sub.2, 10 to 30% by weight of ZnO, 5 to 20% by weight of PbO, 3 to 10% by weight of B.sub.2 O.sub.3, 12-20% by weight of alkaline earth metal oxides selected from the group consisting of MgO, CaO, SrO, and BaO, maximum contents of MgO, CaO, SrO being, respectively, 7% by weight, 3% by weight, 7% by weight, and BaO 7-15% by weight, and optionally not more than 2% by weight of an oxide selected from the group consisting of Bi.sub.2 O.sub.3, CeO.sub.2, In.sub.2 O.sub.3, MnO.sub.2, P.sub.2 O.sub.5, Sb.sub.2 O.sub.3, Ta.sub.2 O.sub.5, V.sub.2 O.sub.5 and Y.sub.2 O.sub.3, the thermal expansion coeffieient of the glass composition being less than 50.times.10.sup.-7 .degree.C..sup.-1.
Dependencies are inferred from the claim text.