Method for selective metallisation of inorganic dielectrics or semiconductors

A method for selective metal plating on an item surface of an item made of an inorganic dielectric or semiconductor material, comprising the steps of:

• surface modification with a pulse laser on the item surface areas to be plated by the metal;
• bringing the item with the laser-modified surface in contact with a pre-treatment solution;
• immersing the item in a catalyst activation bath, and
• metal plating in an electroless metal plating bath,
• wherein the surface modification is performed with an ultrashort pulse laser leading to a static electrical charge formation on the item surface to be plated;
• wherein parameters of the ultrashort laser pulses are chosen such that the static electrical charge formed on the item surface initiates formation of hydroxy groups on the laser-modified surface areas by adsorbing water molecules from ambient;
• wherein the pre-treatment solution contains a mixture of a compound described by a formula of:
• R—OH and water, where R is a radical molecule, which does not dissociate in water;
• wherein upon bringing the item with the laser-modified surface in contact with the pre-treatment solution, R—OH molecules are adsorbed and localised in the laser-modified areas;
• wherein the catalyst activation bath is a metal salt activation bath;
• wherein upon immersing the item in the metal salt catalyst activation bath the localised R—OH molecules on the surface of the item act as reducing agents to facilitate a reduction of metal ions from the catalyst activation bath, thereby forming catalytic seeds exclusively at the laser-modified areas.