Fabrication of Large-Scale Nanopore-Array Patterns with Controllable 3D Geometry via Atomic Migration

Abstract A hybrid manufacturing method named FAST , involving nanotemplate fabrication, film deposition, nanopore pattern formation, and 3D shaping of nanopore channels, is presented and validated for fabricating large-scale, solid-state nanopore-array patterns. Different from conventional single-nanopore fabrication techniques, FAST simultaneously fabricates thousands of uniform nanopores within a defined area, offering exceptional control over pore size, shape, density, and material composition. Experiments demonstrate that FAST can achieve a pore channel length as small as 4 nm. A compact pattern within a 21.4 µm 2 area (SEM field of view) contains over 2100 nanopores while maintaining uniform shape and size and a clear boundary between nanopores. The nanopore quantity and distribution area can be increased over 100 mm 2 , depending on the nanopore size and density. Thermal processing is used to regulate the 3D geometry of nanopores, creating an unprecedented, inhomogeneous pore channel variation within the thin film as determined by the film thickness. Under controlled conditions, the nanopores expand at the top and shrink at the bottom, forming a conical shape with the minimum pore aperture reduced or even closed, as proven by experiments. Substrate restriction facilitates this asymmetric variation, distinct from previously reported observations. To explain this phenomenon, we propose an atomic migration mechanism driven by the energy potential gradient along the nanopore channel and elucidate it through simulation. FAST provides a highly efficient and cost-effective route for the mass production of uniform solid-state nanopores.