Low-temperature baked substrate
AssigneeNgk Spark Plug Co., Ltd.
InventorsKazuo Kondo, Asao Morikawa
Life of this patent
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Abstract
A substrate having a low dielectric constant for use with electronic devices consisting essentially of porous crystalline glass. The composition of the crystalline glass is represented by the formula X-Al.sub.2 O.sub.3 -SiO.sub.2, where X is one or more of the metal oxides ZnO, MgO, Li.sub.2 O, ZrO.sub.2, B.sub.2 O.sub.3, P.sub.2 O.sub.5, Y.sub.2 O.sub.3 and BaO. The crystalline glass may also include a filler material such as a ceramic powder or non-glass material. The substrate initially has a particle size of approximately 5 microns or less, which provides a high mechanical strength to the substrate even at high porosities.
Claims9
A substrate for use with electronic devices, said substrate consisting essentially of porous crystalline glass, said glass having a composition of X-Al.sub.2 O.sub.3 -SiO.sub.2 where X is a metal oxide selected from the group consisting of ZnO, MgO, Li.sub.2 O, ZrO.sub.2, B.sub.2 O.sub.3, P.sub.2 O.sub.5, Y.sub.2 O.sub.3, and BaO, said porous crystalline glass having a particle size of less than about 5 .mu.m and having closed pores distributed therein, at least 50 percent of said pores having a pore diameter of 10 .mu.m or less, said porous crystalline glass further having a porosity from about 30 to about 60 volume percent, said substrate having a dielectric constant of 4.0 or less and having a mechanical strength of about 10 to about 13 kg/mm.sup.2.
A substrate for use with electronic devices, said substrate consisting essentially of porous crystalline glass, said glass composition being selected from the group consisting of ZnO-MgO-Al.sub.2 O.sub.3 -SiO.sub.2, CaO-B.sub.2 O.sub.3 -MgO-Al.sub.2 O.sub.3 -SiO.sub.2, Y.sub.2 O.sub.3 -MgO-Al.sub.2 O.sub.3 -SiO.sub.2, and 2MgO-5Al.sub.2 O.sub.3 -5SiO.sub.2, said porous crystalline glass having a particle size of less than about 5 .mu.m and having closed pores distributed therein, at least 50 percent of said pores having a pore diameter of 10 .mu.m or less, said porous crystalline glass further having a viscosity from about 30 to about 60 volume percent, said substrate having a dielectric constant of 4.0 or less and having a mechanical strength of about 10 to about 13 kg/mm.sup.2.
Dependencies are inferred from the claim text.