Abstract: A substrate includes a non-conductive portion to be electroless-plated of a substrate, on the surface of which fine metal catalyst particles composed of silver nuclei and palladium nuclei each having an average particle size of 1 nm or less adhere at a high nuclei density of 2000 nuclei/&mgr;m2 or more. The metal catalyst particles are produced by sensitizing the non-conductive portion of the substrate by dipping the substrate in a sensitizing solution containing bivalent tin ions, activating the non-conductive portion of the substrate by dipping the substrate in a first activator containing silver ions, and activating the non-conductive portion of the substrate by dipping the substrate in a second activator containing palladium ions.

Abstract: A method for forming a Cu interconnect pattern on a ZnO film of a printed circuit board without using a metallic catalyst on the ZnO film includes the steps of replacing Zn in the ZnO film by Cu in an aqueous solution of copper sulfate to form a CuO film, reducing the CuO in the CuO film to Cu in an aqueous solution of hydrogenated boron potassium to form a metallic Cu film, and plating the metallic Cu film with a plating Cu film in a plating liquid. The absence of the metallic catalyst improves the insulation resistance of the Cu interconnect pattern in the printed circuit board.

Abstract: A substrate includes a non-conductive portion to be electroless-plated of a substrate, on the surface of which fine metal catalyst particles composed of silver nuclei and palladium nuclei each having an average particle size of 1 nm or less adhere at a high nuclei density of 2000 nuclei/&mgr;m2 or more. The metal catalyst particles are produced by sensitizing the non-conductive portion of the substrate by dipping the substrate in a sensitizing solution containing bivalent tin ions, activating the non-conductive portion of the substrate by dipping the substrate in a first activator containing silver ions, and activating the non-conductive portion of the substrate by dipping the substrate in a second activator containing palladium ions.

Abstract: A substrate includes a non-conductive portion to be electroless-plated of a substrate, on the surface of which fine metal catalyst particles composed of silver nuclei and palladium nuclei each having an average particle size of 1 nm or less adhere at a high nuclei density of 2000 nuclei/&mgr;m2 or more. The metal catalyst particles are produced by sensitizing the non-conductive portion of the substrate by dipping the substrate in a sensitizing solution containing bivalent tin ions, activating the non-conductive portion of the substrate by dipping the substrate in a first activator containing silver ions, and activating the non-conductive portion of the substrate by dipping the substrate in a second activator containing palladium ions.

Abstract: A circuit board having a surface thereof on which a catalytic layer is formed initially and a photosensitive plating resist is subsequently applied in a manner such that the applied plating resist is subjected to an exposure for patterning a desired shape of pattern to be then developed, and that by the use of the patterned plating resist, a metallic pattern is formed by the electroless plating. The light of a specific wavelength, which hardens the plating resist, is absorbed by the catalytic layer and does not cause any halation at a boundary between the catalytic layer and the plating resist. Thus, since the plating resist can be patterned in a correct shape, the metallic pattern can be formed to have an accurate shape.