title: A novel vertical fan-out platform based on an array of curved anodic alumina nanochannels.
abstract: Focused ion beam lithography and a two-step anodization have been combined to fabricate a vertical fan-out platform containing an array of unique probes. Each probe comprises three anodic alumina nanochannels with a fan-out arrangement. The lithography is used to pattern an aluminum sheet with a custom-designed array of triangular 'cells' whose apexes are composed of nanoholes. The nanoholes grow into straight nanochannels under proper voltage in the first-step anodization. The second step uses a doubled voltage to induce lateral repulsion among the nanochannels' growth fronts originating in the same cell. Therefore, the fronts fan out. The repulsion roots in the inter-front distance being shorter than the naturally favoured length, which increases with anodization voltage. The fan-out evolution continues until the growth fronts originating in all the cells evolve into a close-packed two-dimensional hexagonal lattice whose spacing is identical to the favoured one. The chemical and physical mechanisms behind the fan-out fabrication are discussed. This novel fan-out platform facilitates probing and handling of many signals from different areas on a sample's surface and is therefore promising for applications in detection and manipulation at the nanoscale level.
authors: Department of Photonics, National Cheng Kung University, Tainan 70101, Taiwan. chihiliu@mail.ncku.edu.tw
authors: Chih-Yi
authors: CY
authors: Liu
authors: Ming-Yu
authors: MY
authors: Lai
authors: Kun-Tong
authors: KT
authors: Tsai
authors: Hsuan-Hao
authors: HH
authors: Chang
authors: Jr-Hau
authors: JH
authors: He
authors: Jessie
authors: J
authors: Shiue
authors: Yuh-Lin
authors: YL
authors: Wang