Contact Instability in Adhesion and Debonding of Thin Elastic Films
Based on experiments and 3-D simulations, we show that a soft elastic film during adhesion and debonding from a rigid flat surface undergoes morphological transitions to pillars, labyrinths and cavities, all of which have the same lateral pattern length scale, close to λ/H ~ 3 for thick films, H > 1 micrometer. The linear stability analysis and experiments show a new thin film regime where λ/H \approx 3+ 2 (γ/3 μH)^(1/4) (γis surface tension, μis shear modulus) because of significant surface energy penalty (for example, λ/H = 6 for H = 200 nm; μ= 1MPa).
cond-mat.soft↗