Low temperature sealing composition with synthetic zircon

摘要

A sealing composition suitable for sealing alumina packages for integrated circuits at a temperature below about 450 DEG C. for a short time of about 10 minutes. The composition is a mixture of 50-80 wt % vitreous solder glass powder of PbO-B2O3 system having a deformation point of 350 DEG C. or less, 1-35 wt % zinc material powder and 1-35 wt % zircon powder. The zircon powder is of a synthetic zircon artificially prepared to eliminate radioactive impurities such as uranium and/or thorium.