INFLUENCE OF BONDING PARAMETERS ON RELIABILITY OF CU WIRE-BONDING TO ELECTROLESS NI/PD/AU PLATING

摘要

We investigated the influence of bonding parameters on the Cu wire-bonding reliability of electroless Ni/Pd/Au. We obtained excellent Cu wire-bonding reliability at optimized bonding parameters (bonding force, ultrasonic power, scrub (circle) number (or number of scrubbing), and scrub (sliding) distance) without over-pressing of the capillary to the plating film. We concluded that the primary factor in the excellent Cu wire-bonding reliability was moderately compressive deformation of the Au-plating film without stack of Au film to the capillary. The compressive deformation of the Cu wire and Au-plating film by scrubbing is necessary to obtain a strong bonding at the Cu-Au interface.