Nanopatterning and electrical tuning of MoS2 layers with a subnanometer helium ion beam
Version 2 2024-06-06, 08:59Version 2 2024-06-06, 08:59
Version 1 2015-09-07, 12:12Version 1 2015-09-07, 12:12
journal contribution
posted on 2024-06-06, 08:59authored byDS Fox, Y Zhou, P Maguire, A O'Neill, C Ó'Coileáin, R Gatensby, AM Glushenkov, T Tao, GS Duesberg, IV Shvets, M Abid, HC Wu, Ying (Ian) ChenYing (Ian) Chen, JN Coleman, JF Donegan, H Zhang
We report subnanometer modification enabled by an ultrafine helium ion beam. By adjusting ion dose and the beam profile, structural defects were controllably introduced in a few-layer molybdenum disulfide (MoS2) sample and its stoichiometry was modified by preferential sputtering of sulfur at a few-nanometer scale. Localized tuning of the resistivity of MoS2 was demonstrated and semiconducting, metallic-like, or insulating material was obtained by irradiation with different doses of He(+). Amorphous MoSx with metallic behavior has been demonstrated for the first time. Fabrication of MoS2 nanostructures with 7 nm dimensions and pristine crystal structure was also achieved. The damage at the edges of these nanostructures was typically confined to within 1 nm. Nanoribbons with widths as small as 1 nm were reproducibly fabricated. This nanoscale modification technique is a generalized approach that can be applied to various two-dimensional (2D) materials to produce a new range of 2D metamaterials.