Formation and healing of defects in atomically thin GaSe and InSe

Hopkinson, David G.; Z�lyomi, Viktor; Rooney, Aidan P.; Clark, Nick; Terry, Daniel J.; Hamer, Matthew; Lewis, David J.; Allen, Christopher S.; Kirkland, Angus I.; Andreev, Yuri; Kudrynskyi, Zakhar; Kovalyuk, Zakhar; Patan�, Amalia; Fal 'ko, Vladimir I.; Gorbachev, Roman; Haigh, Sarah J.

Abstract

© 2019 American Chemical Society. Two dimensional III-VI metal monochalcogenide materials, such as GaSe and InSe, are attracting considerable attention due to their promising electronic and optoelectronic properties. Here, an investigation of point and extended atomic defects formed in mono-, bi-, and few-layer GaSe and InSe crystals is presented. Using state-of-the-art scanning transmission electron microscopy, it is observed that these materials can form both metal and selenium vacancies under the action of the electron beam. Selenium vacancies are observed to be healable: recovering the perfect lattice structure in the presence of selenium or enabling incorporation of dopant atoms in the presence of impurities. Under prolonged imaging, multiple point defects are observed to coalesce to form extended defect structures, with GaSe generally developing trigonal defects and InSe primarily forming line defects. These insights into atomic behavior could be harnessed to synthesize and tune the properties of 2D post-transition-metal monochalcogenide materials for optoelectronic applications.

Citation

Hopkinson, D. G., Zólyomi, V., Rooney, A. P., Clark, N., Terry, D. J., Hamer, M., Lewis, D. J., Allen, C. S., Kirkland, A. I., Andreev, Y., Kudrynskyi, Z., Kovalyuk, Z., Patanè, A., Fal 'ko, V. I., Gorbachev, R., & Haigh, S. J. (2019). Formation and healing of defects in atomically thin GaSe and InSe. ACS Nano, 13(5), 5112-5123. https://doi.org/10.1021/acsnano.8b08253

• Journal Article Type: Article
• Acceptance Date: Apr 4, 2019
• Online Publication Date: Apr 4, 2019
• Publication Date: May 28, 2019
• Deposit Date: Apr 5, 2019
• Publicly Available Date: Apr 5, 2020
• Journal: ACS Nano
• Print ISSN: 1936-0851
• Electronic ISSN: 1936-086X
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 5
• Pages: 5112-5123
• DOI: https://doi.org/10.1021/acsnano.8b08253
• Keywords: General Engineering; General Physics and Astronomy; General Materials Science
• Public URL: https://nottingham-repository.worktribe.com/output/1752581
• Publisher URL: https://pubs.acs.org/doi/10.1021/acsnano.8b08253
• Additional Information: This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Nano, copyright © American Chemical Society after peer review. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsnano.8b08253
• Contract Date: Apr 5, 2019