FORMATION OF GOLD PLATED ELECTRODE, BOARD AND WIRE BONDING METHOD

摘要

PURPOSE: To realize gold plating having sufficient bonding properties by heating a board to deposit nickel or a nickel compound on the surface of a gold layer and then removing the nickel or nickel compound from the surface of the gold layer to expose an underlying high purity gold layer. CONSTITUTION: A gold layer 2c is formed on a barrier metal layer 2b by substitution electroless plating. Nickel or nickel compound contained in the barrier metal layer is present in the gold layer 2c. When the board 1 is heated, the nickel or nickel compound present in the gold layer 2c is deposited collectively on the surface of the gold layer 2c. When the gold layer 2c is subjected to etching, substantially all nickel or nickel compound is removed from the surface of the gold layer 2c and a a gold layer 2c having enhanced purity is exposed.