Advances in MEMS based Strain Engineering of 2D Materials

Strain on 2D materials is an exciting avenue to explore material properties as well as induce novel phenomena, such as strain-dependent electron-hole plasma (EHP) formation in MoS2, or pseudo-magnetic field generation in graphene. In this work, we successfully incorporate MoS2 and graphene with microelectromechanical systems (MEMS) to controllably introduce strain, while simultaneously observing 2-terminal transport and electro-optical changes. We fabricate suspended 2D material integrated MEMS devices using a novel polymer transfer microstructure without damaging the MEMS or the 2D film. By electrically powering our devices, suspended 2D materials undergo controllable, reversible uniaxial strain which we characterize by optical spectroscopy. Equipped with two-terminal contacts, we explore the conductance of suspended 2D materials while simultaneously straining the material in air, with the goal of achieving different strain gradients for accessing novel physics.