Abstract: Low temperature sealing glass compositions comprising 35 to 80% by weight TeO.sub.2, 15 to 50% V.sub.2 O.sub.5 and 0.1 to 20% Nb.sub.2 O.sub.5, ZrO.sub.2 and/or ZnO.
Abstract: Fluid, stable glasses useful for low-temperature sealing applications are made by adding jointly bismuth oxide, zinc oxide, phosphorus pentoxide, titania and/or zirconium oxide to the lead oxide vanadium oxide binary. The phosphorus pentoxide may be replaced partially or entirely with niobium pentoxide and/or tantalum oxide.Sealing glass compositions comprising these low-melting lead-vanadia glasses in powder form and refractory fillers of lower thermal expansion for use in hermetically sealing semiconductor devices in ceramic packages are disclosed. Group V metal oxides, particularly niobium-containing oxides, are preferred fillers. Silver metal is a preferred filler for making die-attach compositions.
Type:
Grant
Filed:
September 15, 1989
Date of Patent:
May 7, 1991
Assignee:
VLSI Packaging Materials, Inc.
Inventors:
Leo Finkelstein, Maurice E. Dumesnil, Richard R. Tetschlag
Abstract: Extremely low-melting oxide glasses useful in silver/glass die-attach materials are disclosed. These glasses are composed of silver oxide, phosphorus oxide and a third component comprising PbO, CdO, ZnO or combination thereof. Their melting point lies in the 200.degree.-300.degree. C. range.
Abstract: Fluid, stable glasses that are useful for low temperature sealing applications are made by adding jointly bismuth oxide, zinc oxide, and phosphorus pentoxide to the lead oxide-vanadium oxide binary. The phosphorous pentoxide may be replaced partially or entirely with niobium pentoxide and/or tantalum pentoxide. Additives and fillers may be incorporated into the glass composition to enhance the fluidity or adhesive characteristics of the glass, alter its coefficient of linear thermal expansion or make it suitable for die attach application. Group V metal oxides, particularly niobium pentoxide, are preferred fillers for altering the coefficient of linear thermal expansion. Similarly these Group V metal oxides may also be added as particulate fillers to lead borate, lead borosilicate and zinc borate glasses. Silver metal is a preferred filler for making die attach compositions.