Blister Testing Atomic Membranes
Imagine a sheet of paper only one atom thin with atomic bonding similar to diamond. Graphene, a single layer of graphite, is such a structure. Its unique atomic structure gives it remarkable electrical, mechanical, and thermal properties. Moreover, graphene represents only one of a whole class of 2D materials that include metals, insulators, and semiconductors. It is the mechanical properties of these materials that fascinate our group the most. They are the thinnest materials in the world and impermeable to standard gases. We suspend 2D materials over microcavities etched in silicon dioxide and utilize this remarkable gas impermeability to apply a pressure difference across the membrane. This results in a pressurized blister test that allows us to introduce controlled strain in the membrane. In this talk, I will focus on our recent experimental results utilizing the pressurized blister test on molybdenum disulfide, MoS2, to measure its adhesive interaction with a substrate and apply large biaxial strain which tunes its electronic band structure.