Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe2-x Crystals

Masoud Mahjouri-Samani; Liangbo Liang; Akinola Oyedele; Yong Sung Kim; Mengkun Tian; Nicholas Cross; Kai Wang; Ming Wei Lin; Abdelaziz Boulesbaa; Christopher M. Rouleau; Alexander A. Puretzky; Kai Xiao; Mina Yoon; Gyula Eres; Gerd Duscher; Bobby G. Sumpter; David B. Geohegan

doi:10.1021/acs.nanolett.6b02263

Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe_2-x Crystals

Masoud Mahjouri-Samani, Liangbo Liang, Akinola Oyedele, Yong Sung Kim, Mengkun Tian, Nicholas Cross, Kai Wang, Ming Wei Lin, Abdelaziz Boulesbaa, Christopher M. Rouleau, Alexander A. Puretzky, Kai Xiao, Mina Yoon, Gyula Eres, Gerd Duscher, Bobby G. Sumpter, David B. Geohegan

Research output: Contribution to journal › Article › peer-review

137 Scopus citations

Abstract

Defect engineering has been a critical step in controlling the transport characteristics of electronic devices, and the ability to create, tune, and annihilate defects is essential to enable the range of next-generation devices. Whereas defect formation has been well-demonstrated in three-dimensional semiconductors, similar exploration of the heterogeneity in atomically thin two-dimensional semiconductors and the link between their atomic structures, defects, and properties has not yet been extensively studied. Here, we demonstrate the growth of MoSe_2-x single crystals with selenium (Se) vacancies far beyond intrinsic levels, up to ∼20%, that exhibit a remarkable transition in electrical transport properties from n- to p-type character with increasing Se vacancy concentration. A new defect-activated phonon band at ∼250 cm^-1 appears, and the A_1g Raman characteristic mode at 240 cm^-1 softens toward ∼230 cm^-1 which serves as a fingerprint of vacancy concentration in the crystals. We show that post-selenization using pulsed laser evaporated Se atoms can repair Se-vacant sites to nearly recover the properties of the pristine crystals. First-principles calculations reveal the underlying mechanisms for the corresponding vacancy-induced electrical and optical transitions.

Original language	English
Pages (from-to)	5213-5220
Number of pages	8
Journal	Nano Letters
Volume	16
Issue number	8
DOIs	https://doi.org/10.1021/acs.nanolett.6b02263
State	Published - Aug 10 2016

Funding

Synthesis science including crystal growth, processing, optical characterization, TEM analysis, AFM studies (M.M.S., K.W., G.E., D.B.G., C.M.R., A.A.P., G.D., M.T., N.C.) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division and performed in part as a user project at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Characterization science at CNMS including lithography and device fabrication, electrical transport measurements, and theoretical calculations (K.X., M.W.L., A.O., B.G.S., A.B., M.Y.) were performed at the Center for Nanophase Materials Sciences, a US Department of Energy Office of Science User Facility. L.L. was supported by a Eugene P. Wigner Fellowship at the Oak Ridge National Laboratory. Y.S.K. was supported by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. DOE.

Keywords

Raman scattering
Transitional metal dichalcogenides
electrical properties
optical properties
vacancies

Access to Document

10.1021/acs.nanolett.6b02263

Cite this

Mahjouri-Samani, M., Liang, L., Oyedele, A., Kim, Y. S., Tian, M., Cross, N., Wang, K., Lin, M. W., Boulesbaa, A., Rouleau, C. M., Puretzky, A. A., Xiao, K., Yoon, M., Eres, G., Duscher, G., Sumpter, B. G., & Geohegan, D. B. (2016). Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe_2-x Crystals. Nano Letters, 16(8), 5213-5220. https://doi.org/10.1021/acs.nanolett.6b02263

@article{911844b0636a4d5091957e8c2c68f9a3,

title = "Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe2-x Crystals",

abstract = "Defect engineering has been a critical step in controlling the transport characteristics of electronic devices, and the ability to create, tune, and annihilate defects is essential to enable the range of next-generation devices. Whereas defect formation has been well-demonstrated in three-dimensional semiconductors, similar exploration of the heterogeneity in atomically thin two-dimensional semiconductors and the link between their atomic structures, defects, and properties has not yet been extensively studied. Here, we demonstrate the growth of MoSe2-x single crystals with selenium (Se) vacancies far beyond intrinsic levels, up to ∼20%, that exhibit a remarkable transition in electrical transport properties from n- to p-type character with increasing Se vacancy concentration. A new defect-activated phonon band at ∼250 cm-1 appears, and the A1g Raman characteristic mode at 240 cm-1 softens toward ∼230 cm-1 which serves as a fingerprint of vacancy concentration in the crystals. We show that post-selenization using pulsed laser evaporated Se atoms can repair Se-vacant sites to nearly recover the properties of the pristine crystals. First-principles calculations reveal the underlying mechanisms for the corresponding vacancy-induced electrical and optical transitions.",

keywords = "Raman scattering, Transitional metal dichalcogenides, electrical properties, optical properties, vacancies",

author = "Masoud Mahjouri-Samani and Liangbo Liang and Akinola Oyedele and Kim, {Yong Sung} and Mengkun Tian and Nicholas Cross and Kai Wang and Lin, {Ming Wei} and Abdelaziz Boulesbaa and Rouleau, {Christopher M.} and Puretzky, {Alexander A.} and Kai Xiao and Mina Yoon and Gyula Eres and Gerd Duscher and Sumpter, {Bobby G.} and Geohegan, {David B.}",

note = "Publisher Copyright: {\textcopyright} 2016 American Chemical Society.",

year = "2016",

month = aug,

day = "10",

doi = "10.1021/acs.nanolett.6b02263",

language = "English",

volume = "16",

pages = "5213--5220",

journal = "Nano Letters",

issn = "1530-6984",

publisher = "American Chemical Society",

number = "8",

}

Mahjouri-Samani, M, Liang, L, Oyedele, A, Kim, YS, Tian, M, Cross, N, Wang, K, Lin, MW, Boulesbaa, A, Rouleau, CM , Puretzky, AA , Xiao, K , Yoon, M , Eres, G, Duscher, G, Sumpter, BG & Geohegan, DB 2016, 'Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe_2-x Crystals', Nano Letters, vol. 16, no. 8, pp. 5213-5220. https://doi.org/10.1021/acs.nanolett.6b02263

TY - JOUR

T1 - Tailoring Vacancies Far beyond Intrinsic Levels Changes the Carrier Type and Optical Response in Monolayer MoSe2-x Crystals

AU - Mahjouri-Samani, Masoud

AU - Liang, Liangbo

AU - Oyedele, Akinola

AU - Kim, Yong Sung

AU - Tian, Mengkun

AU - Cross, Nicholas

AU - Wang, Kai

AU - Lin, Ming Wei

AU - Boulesbaa, Abdelaziz

AU - Rouleau, Christopher M.

AU - Puretzky, Alexander A.

AU - Xiao, Kai

AU - Yoon, Mina

AU - Eres, Gyula

AU - Duscher, Gerd

AU - Sumpter, Bobby G.

AU - Geohegan, David B.

PY - 2016/8/10

Y1 - 2016/8/10

N2 - Defect engineering has been a critical step in controlling the transport characteristics of electronic devices, and the ability to create, tune, and annihilate defects is essential to enable the range of next-generation devices. Whereas defect formation has been well-demonstrated in three-dimensional semiconductors, similar exploration of the heterogeneity in atomically thin two-dimensional semiconductors and the link between their atomic structures, defects, and properties has not yet been extensively studied. Here, we demonstrate the growth of MoSe2-x single crystals with selenium (Se) vacancies far beyond intrinsic levels, up to ∼20%, that exhibit a remarkable transition in electrical transport properties from n- to p-type character with increasing Se vacancy concentration. A new defect-activated phonon band at ∼250 cm-1 appears, and the A1g Raman characteristic mode at 240 cm-1 softens toward ∼230 cm-1 which serves as a fingerprint of vacancy concentration in the crystals. We show that post-selenization using pulsed laser evaporated Se atoms can repair Se-vacant sites to nearly recover the properties of the pristine crystals. First-principles calculations reveal the underlying mechanisms for the corresponding vacancy-induced electrical and optical transitions.

AB - Defect engineering has been a critical step in controlling the transport characteristics of electronic devices, and the ability to create, tune, and annihilate defects is essential to enable the range of next-generation devices. Whereas defect formation has been well-demonstrated in three-dimensional semiconductors, similar exploration of the heterogeneity in atomically thin two-dimensional semiconductors and the link between their atomic structures, defects, and properties has not yet been extensively studied. Here, we demonstrate the growth of MoSe2-x single crystals with selenium (Se) vacancies far beyond intrinsic levels, up to ∼20%, that exhibit a remarkable transition in electrical transport properties from n- to p-type character with increasing Se vacancy concentration. A new defect-activated phonon band at ∼250 cm-1 appears, and the A1g Raman characteristic mode at 240 cm-1 softens toward ∼230 cm-1 which serves as a fingerprint of vacancy concentration in the crystals. We show that post-selenization using pulsed laser evaporated Se atoms can repair Se-vacant sites to nearly recover the properties of the pristine crystals. First-principles calculations reveal the underlying mechanisms for the corresponding vacancy-induced electrical and optical transitions.

KW - Raman scattering

KW - Transitional metal dichalcogenides

KW - electrical properties

KW - optical properties

KW - vacancies

UR - http://www.scopus.com/inward/record.url?scp=84981501518&partnerID=8YFLogxK

U2 - 10.1021/acs.nanolett.6b02263

DO - 10.1021/acs.nanolett.6b02263

M3 - Article

AN - SCOPUS:84981501518

SN - 1530-6984

VL - 16

SP - 5213

EP - 5220

JO - Nano Letters

JF - Nano Letters

IS - 8

ER -