| 摘要 |
PURPOSE:To subject only the inner wall of a hole in a copper-lined laminated board to electroless plating by leaving catalyst nuclei only on the inner wall and carrying out plating under specified conditions using a specified electroless Ni plating bath. CONSTITUTION:Catalyst nuclei are stuck to the whole surface of a copper-lined laminated board including the inner wall of a hole pierced in the board, and the catalyst nuclei on the surface of the copper foil of the board are removed by planing to leave the catalyst nuclei only on the inner wall of the hole. The board is then immersed in an electroless Ni plating bath of 2.1-2.6pH at 65- 75 deg.C. The plating bath contains 3-9g/l (expressed in terms of Ni) Ni salt, 15- 30g/l sodium citrate and 30-50g/l sodium hypophosphite. Only the inner wall of the hole in the copper lined laminated board is subjected to electroless Ni plating. |
