Alternative robust reliability solution for silver finishing

Abstract

In this paper, a silver adhesion promoter process, namely “AgPrep” was introduced for the semiconductor leadframes. The concept of how AgPrep works to improve the adhesion between the silver surface of a leadframe and the epoxy molding compound (EMC) was presented. X-ray Photoelectron Spectroscopy (XPS) analysis was also carried out to study the chemical state of the silver surface after AgPrep's treatment. Besides, the surface energy of AgPrep's treated silver was characterized through the contact angle measurements using a drop shape analyzer. Finally, the adhesion performance of AgPrep process was verified in the button shear tests and a series of reliability tests.