abstract
Two-dimensional transition-metal dichalcogenides (TMDs) have a strain-sensitive nature and can only exhibit in plane piezoelectricity, owing to their in-plane inversion symmetry breaking, which limits their practical applications for vertical stimulations. In this study, we demonstrated the capability of focused ion beams to create out of-plane piezoelectricity on multi-layered MoTe2. We utilized a focused helium ion beam to selectively pattern the out-of-plane piezoelectricity via defect engineering in a layered MoTe2 flake. The generated out-of-plane piezoelectricity in the desired area was quantitatively examined using atomic force microscopy, and ion beam irradiation-induced defect formation that gave rise to inversion symmetry breaking was confirmed. These results indicated that the out-of-plane piezoelectricity can be selectively patterned through a focused helium ion beam, and it is expected that this approach can also be applied to other classes of TMDs and can expand the application fields of TMD-based devices.
keywords
ATOMIC-LAYER MOS2; CARBON CONTAMINATION; TRANSPORT-PROPERTIES; FORCE MICROSCOPY; MONOLAYER MOS2; TRANSITION; SUBSURFACE; ENERGY; DAMAGE
subject category
Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied
authors
Seol, D; Kim, S; Jang, WS; Jin, Y; Kang, S; Kim, S; Won, D; Lee, C; Kim, YM; Lee, J; Yang, H; Jeong, MS; Belianinov, A; Tselev, A; Somnath, S; Smith, CR; Ovchinnikova, OS; Balke, N; Kim, Y
our authors
acknowledgements
This work was supported by a National Research Foundation of Korea (NRF), Republic of Korea grant funded by the Korean government (MSIT) (Nos. NRF-2017R1A2B2003342 and 2020R1F1A1072355). It was also supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2019R1A6A1A03033215). The He+ ion beam irradiation and AFM measurements were conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility (CNMS2017-006). This work was partially supported by IBS-R011-D1 and the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2019R1C1C1010556). In part (A.T.), this work was developed within the scope of the project CICECO-Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020), financed by national funds through the FCT/MEC, Portugal and when appropriate co-financed by FEDER, Portugal under the PT2020 Partnership Agreement.