Characterisation of directly bonded silicon wafers by means of the double cantilever crack opening method

The influence of the specimen geometry, the elastic anisotropy the testing conditions and measurement errors on the determination of the interface energy of directly bonded wafers with the double cantilever beam (DCB) method (crack opening method) is investigated showed that the analytical DCB-solution can exactly only be applied to beam-like samples while the analysis of test results derived from complete wafer pairs requires numerical methods. The investigations also revealed that the measurement of the crack length with a near infrared camera yielded systematically too small crack lengths. For beam bending theory. Furthermore, using an appropriate Young's modulus allows to consider the influence of anisotropy. In the case of complete wafer pairs a similiar correction requires numerical simulation methods.