Thermo-Optical Arrays of Flexible Nanoscale Nanomembranes Freely Suspended over Microfabricated Cavities as IR Microimagers

We fabricated an array of microscopic cavities sealed with a freely suspended layer-by-layer nanomembrane. We observed that the convex−concave shape transition controlled by thermal expansion and contraction of air in the sealed microcavities facilitates a fast optical response to minute temperature variations and allows for direct visualization of the IR laser beam footprint in real time. Such sealed cavity arrays will pave the way toward a new generation of uncooled, miniature, ultrasensitive, thermal microimagers.