Identification and analysis of ion-implanted chromium dopants in monolayer MoS2
- Abstract number
- 319
- Presentation Form
- Poster Flash Talk + Poster
- Corresponding Email
- [email protected]
- Session
- Stream 1: EMAG - 2D Materials
- Authors
- Mr. Michael Hennessy (3), Dr. Eoghan O'Connell (3), Mr. Manuel Auge (1), Mr. Stefan Rost (2), Mr. Minh Bui (2), Mr. Eoin Moynihan (3), Prof. Beata Kardynal (2), Prof. Hans Hofsäss (1), Prof. Ursel Bangert (3)
- Affiliations
-
1. Georg-August-Universität Göttingen
2. Peter Grünberg Institute
3. University of Limerick
- Keywords
2D materials, HAADF STEM, EELS, ion implantation, semiconductors
- Abstract text
The remarkable physical properties of monolayer thick transition metal dichalcogenides (TMDCs), resulting from their two dimensional (2D) geometry and lattice symmetry, make them an exciting platform for developing photonic devices with new functionalities [1]. Monolayer TMDCs can be easily incorporated into electrically driven devices, which in turn can be coupled to optical microcavities or photonic circuits [2]. In order to make such devices a reality, modification methods tailored for these materials must be developed. Ultra-low energy (10-25 eV) ion implantation [3,4] of monolayer TMDCs is carried out using the ADONIS mass-selected ion beam deposition system at the University of Gottingen [5]. This novel technique allows for highly pure, clean and selective substitutional incorporation of dopants [6] and is compatible with standard semiconductor processing. Additionally, post-growth doping [7] of TMDCs offers an expanded selection of possible dopants compared to the popular method of doping via CVD growth.
Here we present results of ultra-low energy ion implantation of chromium into monolayer MoS2. Ab initio band structure calculations are first used to analyse the suitability of MoS2 for electronic tailoring via ion implantation. Atomic resolution high angle annular dark field (HAADF scanning transmission electron microscopy (STEM), together with core-loss electron energy loss spectroscopy (EELS) analysis, is used to identify individual dopant atoms in the host lattice and examine the atomic structure of the defects and dopants in the monolayers. Strain induced at dopant sites in the lattice is analysed and quantified using 4D-STEM. Analysis of experimental HAADF STEM and 4D-STEM data is carried out using the Temul Toolkit Python library [8], based on Atomap [9]. Low loss EELS is used in conjunction with low temperature photoluminescence to study excitonic behavior at the strained implantation sites.
This work constitutes a proof-of-principle study to incorporate implanted TMDCs into non-classical single photon emitting diodes [10]. The development of such devices has far-reaching implications for emerging technologies such as quantum cryptography and quantum metrology.
The authors gratefully acknowledge funding from Volkswagenstiftung.
- References
[1] K. Mak, C. Lee, J. Hone, J. Shan, and T. Heinz, Phys. Rev. Lett. 105, 136805 (2010).
[2] K. Mak and J. Shan, Nat. Photonics 10, 216 (2016).
[3] K. Dolui, I. Rungger, C. Das Pemmaraju, and S. Sanvito, 1 (2013).
[4] V. P. Pham and G. Y. Yeom, Adv. Mater. 28, 9024 (2016).
[5] M. Uhrmacher and H. Hofsäss, Nucl. Instruments Methods Phys. Res. Sect. B Beam Interact. with Mater. Atoms 240, 48 (2005).
[6] J. W. Mayer, 1973 Int. Electron Devices Meet. 3 (1973).
[7] A. Azcatl, X. Qin, A. Prakash, C. Zhang, L. Cheng, Q. Wang, N. Lu, M. J. Kim, J. Kim, K. Cho, R. Addou, C. L. Hinkle, J. Appenzeller, and R. M. Wallace, ArXiv In Press, 1 (2016).
[8] E. O’Connell, M. Hennessy and E. Moynihan, PinkShnack/TEMUL: DOI Release. https://doi.org/10.5281/ZENODO.3832143 (2020).
[9] M. Nord, P. E. Vullum, I. MacLaren, T. Tybell, and R. Holmestad, Adv. Struct. Chem. Imaging 3, 9 (2017).
[10] M. D. Eisaman, J. Fan, A. Migdall, Acta Med. Okayama 67, 259 (2013).