Fracture and wrinkle patterns of metal/elastomer bilayers on glass slides induced by high temperature annealing

Highlights: • PDMS spin-coated on glass and silver films sputter deposited on PDMS. • PDMS becomes brittle and fractures after high temperature annealing. • It contains four stages: crack-free, isolated crack, long strip piece and polygonal fragment. • Multiple wrinkles are observed in the films due to curvature-induced compression. • The fracture and wrinkle patterns are discussed based on stress theory. -- Abstract: Inorganic-organic multilayer systems are ubiquitous in many important technological applications and have received considerable attention recently. Although the mechanics, structures, materials and performances of multilayer devices under room temperature have been extensively investigated, the effect of heat on the inorganic-organic composite systems remains unclear. Here we report on the fracture and wrinkle behaviors of metal/elastomer (silver/polydimethylsiloxane(PDMS)) bilayers resting on glass slides induced by high temperature annealing. It is found that as the annealing temperature is beyond a critical value, the PDMS layer is fractured and detaches from the glass slide due to the thermal contraction during cooling. The fractured PDMS layer bends upward and places the silver film under a compressive stress, which is relieved by formation of multiple wrinkle patterns. The morphological characteristics, evolutional behaviors and potential mechanisms of both fracture and wrinkle patterns are discussed in detail. The report in this work could promote better understanding of the effect of heat on the mechanical durability of metal/elastomer/solid multilayer systems.