Method for measuring fracture toughness of wafer-bonded interfaces with high spatial resolution

Journal article, 2006

A test method for adhesion quantification with high spatial resolution of bonded areas is presented. The method is based on a three-point bend chevron test and is applicable especially for small bonded structures. Using an ordinary surface profiler the method is suitable for determining the mode I fracture toughness, K Ic , of bonded areas from 5 × 5 νm 2 to 20 × 20 νm 2 in size. The method is compared quantitatively to the double cantilever beam (DCB) test. Measurements show that the average K Ic value determined using this method is in close accordance with K Ic values measured using the DCB method but a larger spread is observed which may be dedicated to a real spatial variation of K Ic shown by the higher spatial resolution of the presented method. © 2006 IOP Publishing Ltd.