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Direct optical-structure correlation in atomically thin dichalcogenides and heterostructures

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Abstract

Atomically thin transition metal dichalcogenides (TMDs) have distinct opto-electronic properties including enhanced luminescence and high on-off current ratios, which can be further modulated by making more complex TMD heterostructures. However, resolution limits of conventional optical methods do not allow for direct nanoscale optical-structural correlation measurements in these materials, particularly of buried interfaces in TMD heterostructures. Here we use, for the first time, electron beam induced cathodoluminescence in a scanning transmission electron microscope (CL-STEM) to measure optical properties of monolayer TMDs (WS2, MoS2 and WSSe alloy) encapsulated between layers of hBN. We observe dark areas resulting from localized (~ 100 nm) imperfect interfaces and monolayer folding, which shows that the intimate contact between layers in this application-relevant heterostructure is required for proper inter layer coupling. We also realize a suitable imaging method that minimizes electron-beam induced changes and provides measurement of intrinsic properties. To overcome the limitation of small electron interaction volume in TMD monolayer (and hence low photon yield), we find that encapsulation of TMD monolayers with hBN and subsequent annealing is important. CL-STEM offers to be a powerful method to directly measure structure-optical correspondence in lateral or vertical heterostructures and alloys.

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References

  1. Mak, K. F.; Lee, C.; Hone, J.; Shan, J.; Heinz, T. F. Atomically thin MoS2: A new direct-gap semiconductor. Phys. Rev. Lett.2010, 105, 136805.

    Article  CAS  Google Scholar 

  2. Splendiani, A.; Sun, L.; Zhang, Y. B.; Li, T. S.; Kim, J.; Chim, C. Y.; Galli, G.; Wang, F. Emerging photoluminescence in monolayer MoS2. Nano Lett.2010, 10, 1271–1275.

    Article  CAS  Google Scholar 

  3. Chernikov, A.; Berkelbach, T. C.; Hill, H. M.; Rigosi, A.; Li, Y. L.; Aslan, O. B.; Reichman, D. R.; Hybertsen, M. S.; Heinz, T. F. Exciton binding energy and nonhydrogenic Rydberg series in monolayer WS2. Phys. Rev. Lett.2014, 113, 076802.

    Article  CAS  Google Scholar 

  4. Zhu, B. R.; Chen, X.; Cui, X. D. Exciton binding energy of monolayer WS2. Sci. Rep.2015, 5, 9218.

    Article  CAS  Google Scholar 

  5. Bogaert, K.; Liu, S.; Chesin, J.; Titow, D.; Gradečak, S.; Garaj, S. Diffusion-mediated synthesis of MoS2/WS2 lateral heterostructures. Nano Lett.2016, 16, 5129–5134.

    Article  CAS  Google Scholar 

  6. Frisenda, R.; Molina-Mendoza, A. J.; Mueller, T.; Castellanos-Gomez, A.; Van Der Zant, H. S. J. Atomically thin p-n junctions based on two-dimensional materials. Chem. Soc. Rev.2018, 47, 3339–3358.

    Article  CAS  Google Scholar 

  7. Wang, Q. H.; Kalantar-Zadeh, K.; Kis, A.; Coleman, J. N.; Strano, M. S. Electronics and optoelectronics of two-dimensional transition metal dichalcogenides. Nat. Nanotechnol.2012, 7, 699–712.

    Article  CAS  Google Scholar 

  8. Singh, A.; Tran, K.; Kolarczik, M.; Seifert, J.; Wang, Y. P.; Hao, K.; Pleskot, D.; Gabor, N. M.; Helmrich, S.; Owschimikow, N. et al. Long-lived valley polarization of intravalley trions in monolayer WSe2. Phys. Rev. Lett.2016, 117, 257402.

    Article  Google Scholar 

  9. Teng, F.; Hu, K.; Ouyang, W. X.; Fang, X. S. Photoelectric detectors based on inorganic p-type semiconductor materials. Adv. Mater.2018, 30, 1706262.

    Article  CAS  Google Scholar 

  10. Cadiz, F.; Courtade, E.; Robert, C.; Wang, G.; Shen, Y.; Cai, H.; Taniguchi, T.; Watanabe, K.; Carrere, H.; Lagarde, D. et al. Excitonic linewidth approaching the homogeneous limit in MoS2-based van der Waals heterostructures. Phys. Rev. X2017, 7, 021026.

    Google Scholar 

  11. Zhang, C. D.; Chuu, C. P.; Ren, X. B.; Li, M. Y.; Li, L. J.; Jin, C. H.; Chou, M. Y.; Shih, C. K. Interlayer couplings, Moiré patterns, and 2D electronic superlattices in MoS2/WSe2 hetero-bilayers. Sci. Adv.2017, 3, e1601459.

    Article  CAS  Google Scholar 

  12. Novoselov, K. S.; Mishchenko, A.; Carvalho, A.; Castro Neto, A. H. 2D materials and van der Waals heterostructures. Science2016, 353, aac9439.

    Article  CAS  Google Scholar 

  13. Dean, C. R.; Young, A. F.; Meric, I.; Lee, C.; Wang, L.; Sorgenfrei, S.; Watanabe, K.; Taniguchi, T.; Kim, P.; Shepard, K. L. et al. Boron nitride substrates for high-quality graphene electronics. Nat. Nanotechnol.2010, 5, 722–726.

    Article  CAS  Google Scholar 

  14. Tran, K.; Singh, A.; Seifert, J.; Wang, Y. P.; Hao, K.; Huang, J. K.; Li, L. J.; Taniguchi, T.; Watanabe, K.; Li, X. Q. Disorder-dependent valley properties in monolayer WSe2. Phys. Rev. B2017, 96, 041302.

    Article  Google Scholar 

  15. Movva, H. C. P.; Fallahazad, B.; Kim, K.; Larentis, S.; Taniguchi, T.; Watanabe, K.; Banerjee, S. K.; Tutuc, E. Density-dependent quantum Hall states and Zeeman splitting in monolayer and bilayer WSe2. Phys. Rev. Lett.2017, 118, 247701.

    Article  Google Scholar 

  16. Pizzocchero, F.; Gammelgaard, L.; Jessen, B. S.; Caridad, J. M.; Wang, L.; Hone, J.; Bøggild, P.; Booth, T. J. The hot pick-up technique for batch assembly of van der Waals heterostructures. Nat. Commun.2016, 7, 11894.

    Article  CAS  Google Scholar 

  17. Gong, Y. J.; Lin, J. H.; Wang, X. L.; Shi, G; Lei, S. D.; Lin, Z.; Zou, X. L.; Ye, G. L.; Vajtai, R.; Yakobson, B. I. et al. Vertical and in-plane heterostructures from WS2/MoS2 monolayers. Nat. Mater.2014, 13, 1135–1142.

    Article  CAS  Google Scholar 

  18. Fabbri, F.; Rotunno, E.; Cinquanta, E.; Campi, D.; Bonnini, E.; Kaplan, D.; Lazzarini, L.; Bernasconi, M.; Ferrari, C.; Longo, M. et al. Novel near-infrared emission from crystal defects in MoS2 multilayer flakes. Nat. Commun.2016, 7, 13044.

    Article  CAS  Google Scholar 

  19. Bozheyev, F.; Valiev, D.; Nemkayeva, R. Pulsed cathodoluminescence and Raman spectra of MoS2 and WS2 nanocrystals and their combination MoS2/WS2 produced by self-propagating high-temperature synthesis. Appl. Phys. Lett.2016, 108, 093111.

    Article  CAS  Google Scholar 

  20. Zheng, S. J.; So, J. K.; Liu, F. C.; Liu, Z.; Zheludev, N.; Fan, H. J. Giant enhancement of cathodoluminescence of monolayer transitional metal dichalcogenides semiconductors. Nano Lett.2017, 17, 6475–6480.

    Article  CAS  Google Scholar 

  21. Lim, S. K.; Brewster, M.; Qian, F.; Li, Y.; Lieber, C. M.; Gradecak, S. Direct correlation between structural and optical properties of III-V nitride nanowire heterostructures with nanoscale resolution. Nano Lett.2009, 9, 3940–3944.

    Article  CAS  Google Scholar 

  22. Kociak, M.; Zagonel, L. F. Cathodoluminescence in the scanning transmission electron microscope. Ultramicroscopy2017, 176, 112–131.

    Article  CAS  Google Scholar 

  23. Pennycook, S. J.; Brown, L. M.; Craven, A. J. Observation of cathodoluminescence at single dislocations by STEM. Philos. Mag. A1980, 41, 589–600.

    Article  CAS  Google Scholar 

  24. Yamamoto, N.; Spence, J. C. H.; Fathy, D. Cathodoluminescence and polarization studies from individual dislocations in diamond. Philos. Mag. B1984, 49, 609–629.

    Article  CAS  Google Scholar 

  25. Zhou, X.; Lu, M. Y.; Lu, Y. J.; Jones, E. J.; Gwo, S.; Gradecak, S. Nanoscale optical properties of indium gallium nitride/gallium nitride nanodisk-in-rod heterostructures. ACS Nano2015, 9, 2868–2875.

    Article  CAS  Google Scholar 

  26. Hentz, O.; Zhao, Z. B.; Gradecak, S. Impacts of ion segregation on local optical properties in mixed halide perovskite films. Nano Lett.2016, 16, 1485–1490.

    Article  CAS  Google Scholar 

  27. Sutter, P.; Komsa, H. P.; Krasheninnikov, A. V.; Huang, Y.; Sutter, E. Luminescence of defects in the structural transformation of layered tin dichalcogenides. Appl. Phys. Lett.2017, 111, 262102.

    Article  CAS  Google Scholar 

  28. Sutter, P.; Argyropoulos, C.; Sutter, E. Germanium sulfide nano-optics probed by STEM-cathodoluminescence spectroscopy. Nano Lett.2018, 18, 4576–4583.

    Article  CAS  Google Scholar 

  29. Ahn, S.; Kim, G.; Nayak, P. K.; Yoon, S. I.; Lim, H.; Shin, H. J.; Shin, H. S. Prevention of transition metal dichalcogenide photodegradation by encapsulation with h-BN layers. ACS Nano2016, 10, 8973–8979.

    Article  CAS  Google Scholar 

  30. Amani, M.; Taheri, P.; Addou, R.; Ahn, G. H.; Kiriya, D.; Lien, D. H.; Ager III, J. W.; Wallace, R. M.; Javey, A. Recombination kinetics and effects of superacid treatment in sulfur- and selenium-based transition metal dichalcogenides. Nano Lett.2016, 16, 2786–2791.

    Article  CAS  Google Scholar 

  31. Moody, G.; Kavir Dass, C.; Hao, K.; Chen, C. H.; Li, L. J.; Singh, A.; Tran, K.; Clark, G.; Xu, X. D.; Berghäuser, G. et al. Intrinsic homogeneous linewidth and broadening mechanisms of excitons in monolayer transition metal dichalcogenides. Nat. Commun.2015, 6, 8315.

    Article  CAS  Google Scholar 

  32. Komsa, H. P.; Kotakoski, J.; Kurasch, S.; Lehtinen, O.; Kaiser, U.; Krasheninnikov, A. V. Two-dimensional transition metal dichalcogenides under electron irradiation: Defect production and doping. Phys. Rev. Lett.2012, 109, 035503.

    Article  CAS  Google Scholar 

  33. Museur, L.; Anglos, D.; Petitet, J. P.; Michel, J. P.; Kanaev, A. V. Photoluminescence of hexagonal boron nitride: Effect of surface oxidation under UV-laser irradiation. J. Lumin.2007, 127, 595–600.

    Article  CAS  Google Scholar 

  34. Berzina, B.; Korsaks, V.; Trinkler, L.; Sarakovskis, A.; Grube, J.; Bellucci, S. Defect-induced blue luminescence of hexagonal boron nitride. Diamond Relat. Mater.2016, 68, 131–137.

    Article  CAS  Google Scholar 

  35. Conley, H. J.; Wang, B.; Ziegler, J. I.; Haglund, R. F., Jr; Pantelides, S. T.; Bolotin, K. I. Bandgap engineering of strained monolayer and bilayer MoS2. Nano Lett.2013, 13, 3626–3630.

    Article  CAS  Google Scholar 

  36. Rosenberger, M. R.; Chuang, H. J.; McCreary, K. M.; Hanbicki, A. T.; Sivaram, S. V.; Jonker, B. T. Nano-“Squeegee” for the creation of clean 2D material interfaces. ACS Appl. Mater. Interfaces2018, 10, 10379–10387.

    Article  CAS  Google Scholar 

  37. Butun, S.; Tongay, S.; Aydin, K. Enhanced light emission from large-area monolayer MoS2 using plasmonic nanodisc arrays. Nano Lett.2015, 15, 2700–2704.

    Article  CAS  Google Scholar 

  38. Bischak, C. G.; Wai, R. B.; Cherqui, C.; Busche, J. A.; Quillin, S. C.; Hetherington, C. L.; Wang, Z.; Aiello, C. D.; Schlom, D. G.; Aloni, S. et al. Noninvasive cathodoluminescence-activated nanoimaging of dynamic processes in liquids. ACS Nano2017, 11, 10583–10590.

    Article  CAS  Google Scholar 

  39. Zhou, W.; Zou, X. L.; Najmaei, S.; Liu, Z.; Shi, Y. M.; Kong, J.; Lou, J.; Ajayan, P. M.; Yakobson, B. I.; Idrobo, J. C. Intrinsic structural defects in monolayer molybdenum disulfide. Nano Lett.2013, 13, 2615–2622.

    Article  CAS  Google Scholar 

  40. Zan, R.; Ramasse, Q. M.; Jalil, R.; Georgiou, T.; Bangert, U.; Novoselov, K. S. Control of radiation damage in MoS2 by graphene encapsulation. ACS Nano2013, 7, 10167–10174.

    Article  CAS  Google Scholar 

  41. Kotakoski, J.; Jin, C. H.; Lehtinen, O.; Suenaga, K.; Krasheninnikov, A. V. Electron knock-on damage in hexagonal boron nitride monolayers. Phys. Rev. B2010, 82, 113404.

    Article  CAS  Google Scholar 

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Acknowledgements

This work was supported by the Singapore-MIT Alliance for Research and Technology and the National Research Foundation, Prime Minister’s Office, Singapore. The authors acknowledge helpful discussions with Yuan Cao and Kha Tran. This work made use of the MRSEC Shared Experimental Facilities at MIT, supported by the National Science Foundation under award number DMR-1419807. Any opinion, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

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  1. Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02141, USA

    Akshay Singh, Hae Yeon Lee & Silvija Gradečak

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  1. Akshay Singh
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  2. Hae Yeon Lee
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Correspondence to Silvija Gradečak.

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Singh, A., Lee, H.Y. & Gradečak, S. Direct optical-structure correlation in atomically thin dichalcogenides and heterostructures. Nano Res. 13, 1363–1368 (2020). https://doi.org/10.1007/s12274-019-2601-7

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