Capillary adhesion model for contacting micromachined surfaces

A capillary adhesion model for contacting micromachined surfaces is presented. It is found that the effect of plasticity is small while that of surface correlations and disjoining pressure are important. By matching the model to experimental results, we extract the thickness of the disjoining layer vs. relative humidity (RH) and compare it to reported values. The extracted thickness is smaller than those in the literature, which may explain why capillarity effects occur only at relatively high RH in the experiments.

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