Electroadhesion-Mediated Interface Delamination for Assembly of Reconfigurable 3D Mesostructures

Abstract

Recently developed buckling-guided assembly methods provide a unique route to the design and manufacture of 3D mesostructures and microelectronic devices with superior performances and unusual functions. Combined with loading-path controlled strategies and/or active material designs, reconfigurable 3D mesostructures with multiple stable 3D geometries can be formed, holding promising potentials for applications in tunable antennas and multimodal actuators. The existing strategies are, however, limited by the applicable range of material types or requirements for switching between various complicated loading paths. Here, we present an electroadhesion-mediated strategy to achieve controlled adhesion of the 3D mesostructure to the substrate during the buckling-guided assembly. This strategy allows an active control of the delamination behavior in the film/substrate system, such that a variety of reconfigurable 3D mesostructures can be accessed by designing the 2D precursor pattern and electrode layout. An electromechanical model is developed to capture the delamination behavior of the film/substrate system under combined compression and voltage loadings, which agrees well with experimental measurements. Based on this model, an equivalent interface energy is proposed to quantify the contributions of the electroadhesion and van der Waals’ interactions, which also facilitates simulations of the interface delamination with cohesive models in finite element analyses (FEAs). Furthermore, a variety of reconfigurable 3D mesostructures are demonstrated experimentally, and their geometric configurations are in close accordance with the results of FEA using the concept of equivalent interface energy.