Towards quantifying the shear delamination of thin films

Abstract

The design of multilayer stacks in the semiconductor industry requires knowledge of the delamination quantities. Previously, the determination of the mode-II failure has been problematic since the success-rate of current methods is low or the samples require superlayers that potentially alter the stack. We develop a method for mode-II testing that applies an additional normal force, which prevents mode-I opening and buckling. This method requires a nanoindenter with lateral force measurement capabilities and a FIB or lithographically structured sample. The experiments are fast, allowing for high-throughput testing. The method is applied to quantify the mode-II fracture of the Cu–SiO2 interface and we show the origins of the observed size-effect.