Surface instability of curved films under surface van der Waals forces

We investigate the surface instability of a curved film interacting with a curved contactor through the action of van der Waals forces. Any one of the two curved boundaries of the film can be subjected to surface interactions while the other is bonded to a curved rigid substrate. In each case, the corresponding bifurcation is governed by the critical value of the relative film thickness. The effects of Poisson's ratio, surface energy and film thickness on the film's instability are discussed in detail leading to a complete picture of stability and bifurcation in the system.