Direct-Write Nanofabrication Using Helium Ion Microscopy: Selective Disordering of Functional Thin Films

A.J. Rondinone, O. Ovchinnikova, A. Belianinov
Oak Ridge National Laboratory,
United States

Keywords: helium-ion microscopy, nanofabrication, ferroelectric, chalcogenide, 2D

Summary:

Direct-write nanofabrication via high-resolution helium and neon ion-beams presents new opportunities to fabricate structures and control morphology at the nanoscale without the need to expose samples to resists and solvents. But in addition to creating finite 2D structures analogous to those created by traditional lithography, ion beams offer the ability to tailor functionality of materials through selective disordering. For example, helium-ion implantation may be used to disorder epitaxial thin films without removing material, thereby creating virtual boundaries within the films for the purposes of defining a conducting pathway, a ferroelectric bit, or a magnetic domain. Alternatively, one can use defect sites created by ions to control spatially defined chemical reactions. In this talk we will present recent examples from two such experiments using the dual gas helium ion microscope at the ORNL Center for Nanophase Materials Sciences: control of chemistry and ferroelectric structure in a ferroelectric thin-film, and selective disordering of MoSe2 for the purpose of modifying optoelectronic properties.