Comparison of the telephone cord delamination method for measuring interfacial adhesion with the four-point bending method

Abstract

Adhesion of Pt films to Si substrates with a native SiO2 oxide has been investigated using telephone cord induced delamination as well as the four-point bending method. Telephone cord delamination was induced by sputtering a thick compressively stressed overlayer onto the Pt/SiO2 films. The Pt/SiO2 interface fracture energy was obtained by measuring the dimensions of the delaminations and using available fracture mechanics models. Interface fracture energy was also measured using the established four-point bend method with pre-fabricated specimens containing the films sandwiched between two silicon substrates. The results of both methods are compared. Phenomenological and FEM models were used to account for the different loading mode mixities of the two experiments. Analysis of the telephone cord induced delamination was shown to provide similar interface fracture energy values compared to the four-point bend method.