A fracture mechanics model was developed, and experimentally verified, to model stress wave repair of stiction-failed microcantilevers. This model allows us to predict accurately the number of laser pulses, at a specific fluence and wavelength, required to fully repair stiction-failed microcantilevers. The proposed fracture mechanics model includes the strain energy stored in a stiction-failed microcantilever and the strain energy supplied by laser induced stress-waves propagating in the material. The ‘unstuck’ portion of the microcantilever is modeled as a crack so that crack growth reduces the stiction-failed length of the microcantilever. A full range of experiments have been performed to validate the model. Experiments using laser fluences ranging from 0.5 kJ/m2 – 45 kJ/m2 at two different wavelengths have been performed. The experiments are in good agreement with the model predictions. Additionally we have identified practical ranges for irradiation, including a lower bound fluence below which repair is impractical, and an upper bound above which damage to the substrate and microcantilevers occurs.

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