Analysis of failure of nanobelt-coated copper-based leadframe/epoxy-based molding compound systems after pull-out test

Two kinds of nanobelts were coated on the surface of a copper-based leadframe by immersion of leadframe in two kinds of hot alkaline solutions. The nanobelt-coated leadframe sheets were molded with epoxy molding compound (EMC), and the molded bodies were machined to form pull-out test specimens for the purpose of measuring the adhesion strength of the nanobelt-coated leadframe/EMC interfaces. After the pull-out tests, fracture surfaces were analyzed by various techniques to determine the failure path, and the failure path trajectory was studied using finite element (FE) modeling. FE analysis revealed that the shear component plays an important role in determining the failure path of the B-nanobelt-coated copper-based leadframe/EMC system after pull-out tests, and it did not affect the failure path of the A-nanobelt-coated copper-based leadframe/EMC system.