DETERMINATION OF THIN-FILM DEBONDING PARAMETERS FROM TELEPHONE-CORD MEASUREMENTS

Methods are put forward for the determination of the fracture energy a nd kinetic coefficient of thin film/substrate interfaces from measurem ents performed on telephone cord blisters. This work is based on a pre viously proposed model for the characterization of debonding features in compressed thin films. The advantages of the proposed methods stem from the following facts concerning telephone cord blisters: (i) they are spontaneous debonding features, and therefore more amenable than a rtificially contrived features to yield realistic debonding parameters ; (ii) they are very commonly observed in compressed thin films; (iii) as revealed by our model, their boundaries are characterized by a con stant fracture mode mixity, and (iv) the driving force for debonding e quals the fracture energy everywhere on their boundaries.