Single-Layer Graphene Shields Contact Time Dependence of Adhesion Force at Silica Interfaces in Both Humid and Dry...

The relationship between adhesion force and contact time remains poorly understood and warrants further investigation. The effect of the number of graphene layers on the adhesion force at the silica interface remains unclear. To address this, an experimental investigation was conducted. At relative humidities (RHs) of 10 ∼ 90%, force-displacement curves were acquired using atomic force microscopy (AFM) to measure adhesion forces on silica, highly oriented pyrolytic graphite (HOPG), and silica-supported bilayer and single-layer graphene interfaces. At the silica-silica interface, the adhesion force is significantly dependent (increasing) on contact time at low and high RHs but independent at moderate RHs. On HOPG and bilayer graphene interfaces, the adhesion force slightly increases with dwell time at low and moderate RHs with saturation times of 5 ∼ 80 s but becomes independent at high RHs. Moreover, the adhesion force increases differ among various conditions. However, the adhesion behavior of the Si-Si interface across all humidity levels can be modified upon the deposition of single-layer graphene, preventing the adhesion force from increasing with prolonged contact time and thereby reducing the risk of adhesion failure. The outcomes provide insights into the adhesion mechanism and offer guidance for addressing stiction-related issues in graphene-based devices.