Realization of Nanolene: A Planar Array of Perfectly Aligned, Air‐Suspended Nanowires

Air suspension and alignment are fundamental requirements to make the best use of nanowires' unique properties; however, satisfying both requirements is very challenging due to the mechanical instability of air‐suspended nanowires. Here, a perfectly aligned air‐suspended nanowire array called “nanolene” is demonstrated, which has a high mechanical stability owing to a C‐channel‐shaped cross‐section of the nanowires. The excellent mechanical stability is provided through geometrical modeling and finite element method simulations. The C‐channel cross‐section can be realized by top‐down fabrication procedures, resulting in reliable demonstrations of the nanolenes with various materials and geometric parameters. The fabrication process provides large‐area uniformity; therefore, nanolene can be considered as a 2D planar platform for 1D nanowire arrays. Thanks to the high mechanical stability of the proposed nanolene, perfectly aligned air‐suspended nanowire arrays with an unprecedented length of 1 mm (aspect ratio ≈5100) are demonstrated. Since the nanolene can be used in an energy‐efficient nanoheater, two energy‐stringent sensors, namely, an air‐flow sensor and a carbon monoxide gas sensor, are demonstrated. In particular, the gas sensor achieves sub‐10 mW operations, which is a requirement for application in mobile phones. The proposed nanolene will pave the way to accelerate nanowire research and industrialization by providing reliable, high‐performance nanowire devices. A perfectly aligned air‐suspended nanowire array named “nanolene,” which is a 2D platform of 1D nanowire arrays, is demonstrated with high mechanical stability by means of a unique C‐channel‐shaped cross‐section of a nanowire. The proposed fabrication process results in reliable demonstrations of nanolenes with various materials and geometrical parameters. The unprecedented millimeter‐scale nanolenes are demonstrated and applied to advanced nanowire‐based devices.