Fabrication of anisotropic nanomaterial by precise and large-area nanowire operation with focused-ion-beam

This paper presents a fabrication method for anisotropic nanomaterial by operating nanowires by focused-ion-beam (FIB) irradiation. After the preparation of one-dimensional nanowire, FIB irradiation is applied on the nanowire to operate its orientation and morphology by choosing irradiation position and area. On one hand, localized FIB irradiation is employed to precisely operate the morphology of the planar ultra-fine nanowire prepared by FIB induced fluidization and self-perfect process driven by the material diffusion process. On the other hand, large area FIB scanning is applied to achieve the orientation adjustment of high-density nanowire bunch and nano-forest obtained by oxygen plasma etching. When nanowire is irradiated, unbalanced stress is introduced at different side, and thus nanowire bends to balance the stress. Based on this approach, both single and large area of nanowire structure can be controlled, and anisotropic nanomaterial is realized.