The role of surface morphology on interfacial adhesion in IC packaging

The role of surface morphology on moulding compound/leadframe adhesion was investigated. The surface morphology of the leadframe was modified by wet chemical treatments and abrasive blasting. In this study, the electroless Cu treatment was found to be more effective in imparting micro-level roughening than abrasive blasting. The surface roughness was found to improve interfacial adhesion and the results suggested that micro-roughness was more beneficial, rather than macro-roughness, for adhesion enhancement. The inadequacy of using RMS and R_a methods to quantify roughness was discussed. The surface area, surface area difference and power spectral density functions are proposed for more reliable and consistent roughness quantification