Improved Component Assembly on Microcircuitry
Original Publication Date: 1987-Dec-01
Included in the Prior Art Database: 2005-Feb-02
A method is disclosed for the protection of exposed edges of copper lines on etched circuit boards for receiving high density surface mount components (SMCs). The method prevents solder ball formation and eliminates shorts that may occur between adjacent lines. The copper exposed by the artwork defining the lines and pads on a printed circuit card for receiving high density SMCs is electroplated with nickel to prevent excessive undercutting of the copper during etching. To enhance module assembly, the edges of the copper circuitry must also be nickel coated. This is done by an immersion technique.The immersion nickel coats the edges of the circuitry and improves reliability.