An Investigation of Different Leadframe Materials with Plasma Cleaning on Extra-Large Leadframe to Study the Effects of Oxidation against Delamination

This paper discusses the delamination at the Molding Compound and Leadframe interface on very wide leadframe (100x300). The study conducted demonstrates the role the copper oxides in causing delamination and shows two main approaches to limit it: by plasma-cleaning process optimization and leadframe material selection. The mechanism of failure has been confirmed to be related to the formation of thick oxides at the wire bonding stage of the assembly flow by Sequential Electrochemical Reduction Analysis (SERA), X-ray photoelectron spectroscopy (XPS) and Energy Dispersive X-ray analysis (EDX). It has been observed that the plasma cleaning before molding does not prevent such delamination. On the contrary, a not-optimized plasma may cause a higher failure rate.