Abstract: A process for depositing metal or metal alloy on a substrate including treating the substrate surface with an activation solution comprising a source of metal ions so the metal ions are adsorbed on the substrate surface, treating the obtained substrate surface with a treatment solution containing an additive selected from thiols, thioethers, disulphides and sulphur containing heterocycles, and a reducing agent suitable to reduce the metal ions adsorbed on the substrate surface selected from boron based reducing agents, hypophosphite ions, hydrazine and hydrazine derivatives, ascorbic acid, iso-ascorbic acid, sources of formaldehyde, glyoxylic acid, sources of glyoxylic acid, glycolic acid, formic acid, sugars, and salts of aforementioned acids; and subsequently treating the substrate surface with a metallizing solution comprising a source of metal ions to be deposited such that a metal or metal alloy is deposited thereon.

Abstract: A process for depositing metal or metal alloy on a substrate including treating the substrate surface with an activation solution comprising a source of metal ions so the metal ions are adsorbed on the substrate surface, treating the obtained substrate surface with a treatment solution containing an additive selected from thiols, thioethers, disulphides and sulphur containing heterocycles, and a reducing agent suitable to reduce the metal ions adsorbed on the substrate surface selected from boron based reducing agents, hypophosphite ions, hydrazine and hydrazine derivatives, ascorbic acid, iso-ascorbic acid, sources of formaldehyde, glyoxylic acid, sources of glyoxylic acid, glycolic acid, formic acid, sugars, and salts of aforementioned acids; and subsequently treating the substrate surface with a metallizing solution comprising a source of metal ions to be deposited such that a metal or metal alloy is deposited thereon.

Abstract: The invention relates to an electroless aqueous copper plating solution, comprising a source of copper ions, a source of glyoxylic acid as reducing agent, and at least one polyamino disuccinic acid or at least one polyamino monosuccinic acid, or a mixture of at least one polyamino disuccinic acid and at least one polyamino monosuccinic acid as complexing agent, as well as to a method for electroless copper plating utilizing said solution and the use of the solution for the plating of substrates.