Structural and morphological modification of PDMS thick film surfaces by ion implantation with the formation of strain-induced buckling domains
Elastomer films with three-dimensional features self-organized into coherent and semi-coherent buckling domains were created by implanting different species of metal ions and combinations thereof, using a metal evaporation ion source, into quality polydimethylsiloxane films. As a result of the implantation process, functionalized discrete regions of strain-induced surface buckling were created, taking the forms of domains of parallel surface waves, semi-ordered regions and disordered regions. In addition, deep, strain-induced, V-shaped cracks were observed to penetrate well into the elastomer matrix. Characterization was via optical microscopy, X-ray diffraction, atomic force microscopy and high-resolution scanning electron microscopy (SEM) in the form of field emission SEM. It was found that controlling the localized strain by altering the metal ion species can control the frequency of the V-shaped cracks and the properties of the buckled areas. These observations and possible mechanisms for the formation of the cracks and domains are discussed in this paper.