TECHNOLOGY FOCUS - CERAMICS AND GLASS - Preferred Composition: The layer (C) further comprises glass which is chosen from glass comprising 52-88 wt.% lead oxide, 0.5-15 wt.% silica, 05-10 wt.% alumina, 0-22 wt.% zinc oxide, 0-8 wt.% tantalum pentoxide, 0-10 wt.% zirconium dioxide, 0-8 wt.% phosphorus pentoxide, 0-15 wt.% mixture of lithium dioxide, sodium oxide and potassium oxide, 0-12 wt.% boron trioxide, and 0-25 wt.% mixture of ferric oxide, cobaltic oxide, cupric oxide and manganese dioxide, glass comprising 55-90 wt.% bismuth oxide, 1-15 wt.% boron trioxide, 0-20 wt.% silica, 0-13 wt.% zinc oxide, 0-12 wt.% lithium oxide, 0-12 wt.% sodium oxide, 0-12 wt.% potassium oxide, 0-10 wt.% mixture of niobium pentoxide and tantalum pentoxide, and 0-25 wt.% mixture of ferric oxide, cobaltic oxide, cupric oxide and manganese dioxide, and glass comprising 30-32 wt.% mixture of boron trioxide and silica, 0-34 wt.% zinc oxide, 0-22 wt.% titanium oxide, 0-10 wt.% lithium oxide, 0-23 wt.% sodium oxide, 0-13 wt.% potassium oxide, 0-10 wt.% phosphorus pentoxide, 0-13 wt.% mixture of antimony oxide and phosphorus pentoxide, 0-8 wt.% zirconium dioxide, 0-5 wt.% fluorine, and 0-25 wt.% mixture of ferric oxide, cobaltic oxide, cupric oxide and manganese dioxide. The high-conductivity layer paste further comprises glass.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The paste comprises 65-95 wt.%, preferably 78-82 wt.% nickel intermetallic compound, 1-10 wt.%, preferably 3-6 wt.% organic vehicle, 1-10 wt.%, preferably 2-4 wt.% at least one solvent and 1-10 wt.%, preferably 2-6 wt.% glass. The nickel intermetallic compound is chosen from nickel bromide, nickel silicide and nickel phosphide. Preferred Properties: The nickel boride has a particle size of 2-5 mu m. The nickel intermetallic compound is a hot metal paste.    TECHNOLOGY FOCUS - METALLURGY - Preferred Composition: The high-conductivity layer comprises a metal paste chosen from silver, silver-coated nickel and silver-coated copper.