Hafnium diselenide (HfSe2) has a high theoretical carrier mobility but is among the most reactive transition-metal dichalcogenides (TMDs). Herein, we have investigated the air stability of 2H polytype HfSe2 single-crystal thin films by spectroscopic and microscopic techniques. Raman spectroscopy measurements in conjunction with atomic force microscopy reveal the formation of selenium-rich blisters on the surface of the crystals upon air exposure. Transmission electron microscopy analysis indicates that 2H-HfSe2 undergoes a spontaneous phase change to 1T-HfSe2. These results offer Raman spectroscopy as a fast, convenient, non-destructive technique to reliably monitor the surface degradation of TMDs and present an opportunity for further study of phase changes in this material.
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L. Yin, K. Xu, Y. Wen, Z. Wang, Y. Huang, F. Wang, T.A. Shifa, R. Cheng, H. Ma, and J. He: Ultrafast and ultrasensitive phototransistors based on few-layered HfSe2. Appl. Phys. Lett. 109, 213105 (2016).
R. Yue, A.T. Barton, H. Zhu, A. Azcatl, L.F. Pena, J. Wang, X. Peng, N. Lu, L. Cheng, R. Addou, S. McDonnell, L. Colombo, J.W.P. Hsu, J. Kim, M.J. Kim, R.M. Wallace, and C. Hinkle: HfSe2 thin films: 2D transition metal dichalcogenides grown by molecular beam epitaxy. ACS Nano 9, 474–480 (2015).
D.L. Greenaway and R. Nitsche: Preparation and optical properties of group IV–VI2 chalcogenides having the CdI2 structure. J. Phys. Chem. Sol. 26, 1445–1458 (1965).
A. Cingolani, M. Lugara, and F. Levy: Resonance Raman scattering in HfSe2 and HfS2. Phys. Scr. 37, 389–391 (1988).
T.J. Wieting and J.L. Verble: Infrared and Raman Investigations of Long-Wavelength Phonons in Layered Materials, in Electrons and Phonons in Layered Crystal Structures (D. Reidel Publishing Company, Dordrecht, 1979), pp. 324–344.
F.A. Rasmussen and K.S. Thygesen: Computational 2D materials database: electronic structure of transition-metal dichalcogenides and oxides. J. Phys. Chem. C 119, 13169–13183 (2015).
W. Zhang, Z. Huang, W. Zhang, and Y. Li: Two-dimensional semiconductors with possible high room temperature mobility. Nano Res. 7, 1731–1737 (2104).
S. Najmaei, M.R. Neupane, B.M. Nichols, R.A. Burke, A.L. Mazzoni, M.L. Chin, D.A. Rhodes, L. Balicas, A.D. Franklin, and M. Dubey: Cross-plane carrier transport in van der Waals layered materials. Small 14, 1703808 (2018).
G. Mirabelli, C. McGeough, M. Schmidt, E.K. McCarthy, S. Monaghan, I.M. Povey, M. McCarthy, F. Gity, R. Nagle, G. Hughes, A. Cafolla, P.K. Hurley, and R. Duffy: Air sensitivity of MoS2, MoSe2, MoTe2, HfS2, and HfSe2. J. Appl. Phys. 120, 125102 (2016).
A.S. George, Z. Mutlu, R. Ionescu, R.J. Wu, J.S. Jeong, H.H. Bay, Y. Chai, K.A. Mkhoyan, M. Ozkan, and C.S. Ozkan: Wafer scale synthesis and high resolution structural characterization of atomically thin MoS2 layers. Adv. Funct. Matter 24, 7461–7466 (2014).
Z. Mutlu, R.J. Wu, D. Wickramaratne, S. Shahrezaei, L. Chueh, S. Temiz, A. Patalano, M. Ozkan, R.K. Lake, K.A. Mkhoyan, and C.S. Ozkan: Phase engineering of 2D tin sulfides. Small 22, 12 (2016).
X. Zhang, X.-F. Qiao, W. Shi, J.-B. Wu, D.-S. Jiang, and P.-H. Tan: Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material. Chem. Soc. Rev. 44, 2757–2785 (2015).
M. Samadi, N. Sarikhani, M. Zirak, H. Zhang, H.-L. Zhang, and A.Z. Moshfegh: Group 6 transition metal dichalcogenide nanomaterials: synthesis, applications and future perspectives. Nanoscale Horiz. 3, 90–204 (2017).
J. Ribeiro-Soares, R.M. Almeida, E.B. Barros, P.T. Araujo, M.S. Dresselhaus, L.G. Cancado, and A. Jorio: Group theory analysis of phonons in two-dimensional transition metal dichalcogenides. Phys. Rev. B 90, 115438 (2014).
J.S. Kim, J. Kim, J. Zhao, S. Kim, J.H. Lee, Y. Jin, H. Choi, B.H. Moon, J.J. Bae, Y.H. Lee, and S.C. Lim: Electrical transport properties of polymorphic MoS2. ACS Nano 10, 7500–7506 (2016).
C. Ataca, H. Sahin, and S. Ciraci: Stable, single-layer MX2 transition-metal oxides and dichalcogenides in a honeycomb-like structure. J. Phys. Chem. C 116, 8983–8999 (2012).
C. Gong, H. Zhang, W. Wang, L. Colombo, R.M. Wallace, and K. Cho: Band alignment of two-dimensional transition metal dichalcogenides: application in tunnel field effect transistors. Appl. Phys. Lett. 103, 053513 (2013).
Semiconductors: Large size high quality flux zone grown vdW HfSe2 crystals (2018). Available at: http://www.2dsemiconductors.com/hafnium-diselenide-hfse2/ (Accessed April 10, 2018).
H. Li, J. Wu, X. Huang, G. Lu, J. Yang, X. Lu, Q. Xiong, and H. Zhang: Rapid and reliable thickness identification of two-dimensional nanosheets using optical microscopy. ACS Nano 7, 10344–10353 (2013).
G. Yumnam, T. Pandey, and A.K. Singh: High temperature thermoelectric properties of Zr and Hf based transition metal dichalcogenides: a first principles study. J. Chem. Phys. 143, 234704–8 (2015).
K. Nagata, K. Ishibashi, and Y. Miyamoto: Raman and infrared spectra of rhombohedral selenium. Japanese J. Appl. Phys. 20, 463–469 (1981).
S. Song, D.H. Keum, S. Cho, D. Perello, Y. Kim, and Y.H. Lee: Room temperature semiconductor–metal transition of MoTe2 thin films engineered by strain. Nano Lett. 16, 188–193 (2016).
This work was made possible by support from C-SPIN, a funded center of STARnet, through a SRC program sponsored by MARCO and DARPA. Raman measurements were performed in the ACIF at the UC Riverside. TEM analysis was performed in the CFAMM at the UC Riverside. The authors thank Dr. Krassimir N. Bozhilov for his assistance with TEM analysis.
Work performed during postdoctoral studies at the University of California, Riverside.
The supplementary material for this article can be found at https://doi.org/10.1557/mrc.2018.185.
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Cruz, A., Mutlu, Z., Ozkan, M. et al. Raman investigation of the air stability of 2H polytype HfSe2 thin films. MRS Communications 8, 1191–1196 (2018). https://doi.org/10.1557/mrc.2018.185