TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compositions: Bi2O3 additive contains greater than or equal to 99 wt.% Bi2O3. Bi2O3 additive contains no other metal oxide. The composition contains 0.1-0.5 wt.%, preferably 0.15-0.3 wt.% Bi2O3 additive. The composition contains 0.5-10 wt.%, preferably 1-5 wt.% glass frits. Glass frits are formed from lead oxide (PbO), alumina (Al2O3), silica (SiO2), boron trioxide (B2O3), lithium oxide (Li2O), titania (TiO2), zinc oxide (ZnO), phosphorus pentoxide (P2O5), vanadium pentoxide (V2O5), strontium oxide (SrO), calcium oxide (CaO), antimony trioxide (Sb2O3), sulfur dioxide (SO2), arsenic trioxide (As2O3), Bi2O3, thallium(III) oxide (Tl2O3), gallium oxide (Ga2O3), magnesium oxide (MgO), yttrium oxide (Y2O3), zirconium dioxide (ZrO2), manganese(V) oxide (Mn2O5), cobalt(II) oxide (CoO), nickel(II) oxide (NiO), copper(II) oxide (CuO), molybdenum oxide (Mo2O3), ruthenium(IV) oxide (RuO2), tellurium dioxide (TeO2), cadmium oxide (CdO), indium oxide (In2O3), tin(IV) oxide (SnO2), lanthanum oxide (La2O3), and/or barium oxide (BaO). Silicon wafer has 2 overlapping layers, one comprising aluminum (Al) and one comprising Ag on the back side surface of the silicon wafer. Preferred Parameters: Bi2O3 has average particle size of 10-3000 nm, preferably 20-300 nm. Ag powder has particle size (D50) of 0.1-5 mu m, preferably 0.5-2 mu m. Preferred Processes: The method further includes applying 2 overlapping layers, one comprising Al and one comprising Ag the back side surface of the silicon wafer, and firing the coated silicon wafer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compositions: The composition further contains adhesion promoting agent, thixotropic agent, and/or dispersant. The composition contains 75-95 wt.%, preferably 80-92 wt.% Ag powder. The composition contains 0.2-2 wt.%, preferably 0.5-1.5 wt.% organic resin selected from acrylic resin, epoxy resin, phenol resin, alkyd resin, cellulose polymers, polyvinyl alcohol, and/or rosin. The composition contains 2-20 wt.%, preferably 2-8 wt.% solvent selected from texanol, propanol, isopropyl alcohol, ethylene glycol and diethylene glycol derivatives, toluene, xylene, dibutyl carbitol, and/or terpineol. The composition contains 0.1-0.7 wt.%, preferably 0.01-2 wt.% dispersant. The composition contains 0.5-2 wt.% thixotropic agent. Preferred Form: The composition is in the form of a paste. EXAMPLE - No suitable example given.