Wrinkle-free nanomechanical film: Control and prevention of polymer film buckling

For the first time, we report on methods to control and prevent polymer films from buckling. Buckled morphologies were created by thermally cycling or mechanically compressing a poly(dimethylsiloxane) substrate coated with a polyelectrolyte multilayer film. By variation of the dimensions of the surface topography relative to the buckling wavelength (e.g., pattern size is less than, equal to, and greater than the buckling wavelength), the orientation and the local morphology of the buckled films were controlled. On the basis of the information obtained, we demonstrate how to alleviate the unavoidable buckling by incorporating nanoparticles into the film. In addition, we studied the effect of the silica layer that results from oxygen plasma treatment and the critical temperature for permanent film buckling.