Enhanced global digital image correlation for accurate measurement of microbeam bending

Microbeams are simple on-chip test structures used for thin film and MEMS materials characterization. Profilometry can be combined with Euler-Bernoulli (EB) beam theory to extract material parameters, like the E-modulus. Characterization of time-dependent microbeam bending is required, though non-trivial, as it involves long term sub-microscale measurements. Here we propose an enhanced global digital image correlation (GDIC) procedure to analyze time-dependent microbeam bending. Using GDIC we extract the full-field curvature profile from optical profilometry data of thin metal microbeam bending experiments, whilst simultaneously correcting for rigid body motion resulting from drift. This work focusses on the implementation of this GDIC procedure and evaluation of its accuracy through a numerical assessment of the proposed methodology.