Method and apparatus for plating, and plating structure

A method for plating in which at least a hole is plated with a metal, comprising:

• a first step of removing organic material existent in a plating region;
• a second step of hydrophilizing a surface of the plating region after the first step;
• a third step of bonding a coupling agent with the surface hydrophilized by the second step;
• a fourth step of bonding a catalytic metal with the coupling agent at the surface after the third step;
• a fifth step of exposing the catalytic metal to activate after the fourth step;
• and
• a sixth step of electrolessly plating the activated surface after the fifth step, wherein:
• a barrier layer is formed on a surface of at least the hole and thereafter,
• the surface is oxidized to remove the organic material;
• following removal of the organic material, the surface is hydroxylated by treating with an oxidizing agent;
• following the hydroxylation, a silane coupling agent or a titanate coupling agent having an atom or an atomic group that forms a coordinate bond with a metal component in a protective agent for a colloid of the catalytic metal is made to react with the hydroxylated surface;
• following the hydroxylation, the surface is treated with the colloidal solution of the catalytic metal and thereby, the metal component in the protective agent for the colloid of the catalytic metal is reacted with a functional group of the silane coupling agent or the titanate coupling agent to form a coordinate bond;
• following the treatment with the colloidal solution, the protective agent in excess that does not form the coordinate bond is removed to perform an activation treatment in which the catalytic metal is exposed;
• and
• following the activation treatment, the surface that has received the activation treatment is treated with an electroless plating liquid including a chelating agent and a reducing agent containing no alkali metal and thereby, electroless plating with copper or nickel is effected on the surface.