| 摘要 |
PURPOSE:To precipitate selectively metallic copper only on the circuit part by subjecting a circuit board having an insulating material between the circuits to be plated to chemical copper plating with a plating liquid which contains cupric ion, etc. and is added with an inorg. compd. of a group 4B element, etc. CONSTITUTION:The circuit board having the insulating material between the circuits to be plated is subjected to the chemical copper plating with the chemical copper plating liquid which contains the cupric ion, complexing agent for the cupric ion, reducing agent for the cupric ion, the hydroxide of an alkali metal, complexing agent for cuprous ion and polyoxyethylene surface active agent as basic components and is added with the inorg. compd. of the group 4B element or further a cationic surface active agent. Then the chemical copper plating only on the circuit part is thus made possible. A compd. of Si or Ge is preferable for the above-mentioned inorg. compd. and is preferably used in a concn. of 3-30milimole/l. Primary - tertiary alkyl amine salts, etc. are preferably used for the above-mentioned cationic surface active agent in a concn. of 20mg/l - solubility limit. |
