TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The oxygen-containing oxidizer in second step is selected from hydrogen peroxide (H2O2), ozone (O3), sodium persulfate (Na2S2O8), potassium permanganate (KmnO4), nitric acid (HNO3), ammonium nitrate (NH4NO3), sulfuric acid (H2SO4), ammonium sulfate ((NH4)2SO4), ammonium peroxydisulfate ((NH4)2S2O8), potassium peroxydisulfate (K2S2O8), perchloric acid (HClO4), ammonium perchlorate (NH4ClO4), sodium perchlorate (NaClO4), potassium perchlorate (KclO4), periodic acid (HIO4 2H2O), sodium periodate (NaIO4), potassium periodate (KIO4), methanesulfonic acid (CH3SO2OH) or ethylenediamine sulfate (C2H10N2SO4) (preferably hydrogen peroxide or ozone).    TECHNOLOGY FOCUS - METALLURGY - Preferred Components: The noble-metal alloy particle is a binary alloy, ternary alloy or quaternary alloy. The non-noble-metal element is selected from aluminum (Al), gallium (Ga), indium (In), magnesium (Mg), tin (Sn), zinc (Zn), copper (Cu), manganese (Mn), nickel (Ni), cobalt (Co) or antimony (Sb). The binary alloy is selected from binary alloy of silver, binary alloy of gold, binary alloy of platinum, binary alloy of palladium and comprising two noble-metals. The binary alloy of silver is selected from following binary alloys:silver-aluminum (Ag-Al) alloy, silver-gallium (Ag-Ga) alloy, silver-indium (Ag-In) alloy, silver-magnesium (Ag-Mg) alloy, silver-tin (Ag-Sn) alloy, silver-zinc (Ag-Zn) alloy or silver-manganese (Ag-Mn) alloy. The binary alloy of gold is selected from following binary alloys: gold-aluminum (Au-Al) alloy, gold-chromium (Au-Cr) alloy, gold-gallium (Au-Ga) alloy, gold-copper (Au-Cu) alloy, gold-indium (Au-In) alloy, gold-manganese (Au-Mn) alloy, gold-tin (Au-Sn) alloy or gold-zinc (Au-Zn) alloy. The binary alloy of platinum is selected from the following binary alloys: platinum-aluminum (Pt-Al) alloy, platinum-copper (Pt-Cu) alloy, platinum-indium (Pt-In) alloy, platinum-magnesium (Pt-Mg) alloy, platinum-tin (Pt-Sn) alloy, platinum-zinc (Pt-Zn) alloy, platinum-manganese (Pt-Mn) alloy, platinum-nickel (Pt-Ni) alloy or platinum-cobalt (Pt-Co) alloy. The binary alloy of palladium is selected from following binary alloys: palladium-aluminum (Pd-Al) alloy, palladium-copper (Pd-Cu) alloy, palladium-indium (Pd-In) alloy, palladium-magnesium (Pd-Mg) alloy, palladium-tin (Pd-Sn) alloy, palladium-zinc (Pd-Zn) alloy, palladium-manganese (Pd-Mn) alloy, palladium-nickel (Pd-Ni) alloy or palladium-cobalt (Pd-Co) alloy. The binary alloy comprising two noble-metals is selected from following binary alloys: silver-gold (Ag-Au) alloy, silver-platinum (Ag-Pt) alloy, silver-palladium (Ag-Pd) alloy, gold-platinum (Au-Pt) alloy, gold-palladium (Au-Pd) alloy or platinum-palladium (Pt-Pd) alloy. The noble-metal alloy particle is a nanoparticle binary alloy which has a particle feature size less than 10 nanometers or 1-5000 nanometers and is selected from following nanoparticle alloys: silver-nickel (Ag-Ni) nanoparticle alloy, silver-cobalt (Ag-Co) nanoparticle alloy, gold-cobalt (Au-Co) nanoparticle alloy or gold-nickel (Au-Ni) nanoparticle alloy. Preferred Method: The noble-metal alloy particle is formed on the surface of the silicon wafer substrate in first step by: an alloy electroless co-plating technique, alloy electro co-plating technique, alloy electro-phoresis technique, stencil printing technique, ink-jet printing technique, spraying technique, sputtering technique or co-evaporating technique. The method (M1) further involves: removal step which performs partial or complete removal of the noble-metal alloy particle(s) on the surface of the silicon wafer substrate containing the noble-metal alloy particle(s). The removal step is performed using a wet etching process of an aqueous etchant solution selected from hydrochloric acid (HCl) aqueous solution, sulfuric acid (H2SO4) aqueous solution and/or nitric acid (HNO3) aqueous solution.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The acidic compound capable of releasing fluoride ion in the aqueous etchant solution in second step is selected from: hydrogen fluoride (HF), ammonium fluoride (NH4F), ammonium hydrogen fluoride (NH4HF2), metal salt or ammonium salt of hydrogen fluoride, trifluoroacetic acid (CF3CO2H), metal salt or ammonium salt of trifluoroacetic acid, tetrafluoroboric acid (HBF4), metal salt or ammonium salt of tetrafluoroboric acid, hexafluorosilicic acid ((NH4)2(SiF6)), or metal salt or ammonium salt of hexafluorosilicic acid (preferably hydrogen fluoride or ammonium fluoride). EXAMPLE - No suitable example given.