Fabrication and characterization of Au(111)/mica bimaterial microcantilevers for surface sciences nanocalorimetry applications

A microfabrication process for UHV-compatible bimaterial microcantilevers (BMCs) based on ultrapure muscovite mica substrate is presented. The fabricated BMCs are coated with atomically flat Au(111) surfaces exhibiting monoatomic terraces wider than 100 nm. With a BMC of dimension 800 µm 200 µm 15 µm, a deflection sensitivity of 0.1 pmnW is achieved at 77 K in UHV under optical heating. This sensitivity is quantified using tunneling current-distance ( – ) measurements acquired with a scanning tunneling microscope, in which thermally induced bending of the cantilever results in measurable variations of with a resolution of 3 pm. BMCs combining high thermal sensitivity with atomically clean Au(111) enable nanoscale calorimetry with high sensitivity while providing an atomically well-defined platform for molecular surface science.