Patent ID: 6395329
Filing Date: 2002-05-28
Classification: B05D,C23C,H05K,Y10T

Abstract:
A method for coating a printed circuit board having metal pads, metal through-holes or a combination thereof, the metal pads, metal through-holes or the combination thereof being formed of a first metal, the method comprising the steps of:contacting the metal pads, the metal through-holes or the combination thereof with a bright-etch composition to form etched pads, etched through-holes or a combination thereof, the etched pads, the etched through-holes or the combination thereof being formed of the first metal; and contacting the etched pads, the etched through-holes or the combination thereof with a plating composition comprising ions of a second metal, the second metal being different from the first metal, and a tarnish inhibitor, the tarnish inhibitor characterized in that it coexists with the second metal in solution, to form a printed circuit board having pads, through-holes or a combination thereof that are formed of the first metal coated by a separate layer of the second metal and by a layer of the tarnish inhibitor.