The data that I've seen on this subject indicates that very smooth Ni/Au surfaces wire bond poorly. On the other hand, an extremely rough Ni/Au surface also exhibits poor wire bond pull strengths. In general, it seems a "moderately rough" Ni/Au surface provides the best results. Rob Schetty LeaRonal Inc. ---------- ------------------------------------------------------------------------------ ------------------------- A question came up on what the surface finish (smoothness/roughness) should be for wire bond on a land. The plated finsh is typically nickel and a covered with a soft gold finsh. Will hills and valleys in the surface make any difference in the bond strength. Phil Hinton hintpwb1@aol,com