TY - JOUR
T1 - Large-Area 2D Layered MoTe2 by Physical Vapor Deposition and Solid-Phase Crystallization in a Tellurium-Free Atmosphere
AU - Huang, Jyun Hong
AU - Deng, Kuang Ying
AU - Liu, Pang Shiuan
AU - Wu, Chien Ting
AU - Chou, Cheng Tung
AU - Chang, Wen Hao
AU - Lee, Yao Jen
AU - Hou, Tuo Hung
N1 - Publisher Copyright:
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2017/9/8
Y1 - 2017/9/8
N2 - Molybdenum ditelluride (MoTe2) has attracted considerable interest for nanoelectronic, optoelectronic, spintronic, and valleytronic applications because of its modest band gap, high field-effect mobility, large spin–orbit-coupling splitting, and tunable 1T′/2H phases. However, synthesizing large-area, high-quality MoTe2 remains challenging. The complicated design of gas-phase reactant transport and reaction for chemical vapor deposition or tellurization is nontrivial because of the weak bonding energy between Mo and Te. This study reports a new method for depositing MoTe2 that entails using physical vapor deposition followed by a postannealing process in a Te-free atmosphere. Both Mo and Te are physically deposited onto the substrate by sputtering a MoTe2 target. A composite SiO2 capping layer is designed to prevent Te sublimation during the postannealing process. The postannealing process facilitates 1T′-to-2H phase transition and solid-phase crystallization, leading to the formation of high-crystallinity few-layer 2H-MoTe2 with a field-effect mobility of ≈10 cm2 V−1 s−1, the highest among all nonexfoliated 2H-MoTe2 currently reported. Furthermore, 2H-MoS2 and Td-WTe2 can be deposited using similar methods. Requiring no transfer or chemical reaction of metal and chalcogen reactants in the gas phase, the proposed method is potentially a general yet simple approach for depositing a wide variety of large-area, high-quality, 2D layered structures.
AB - Molybdenum ditelluride (MoTe2) has attracted considerable interest for nanoelectronic, optoelectronic, spintronic, and valleytronic applications because of its modest band gap, high field-effect mobility, large spin–orbit-coupling splitting, and tunable 1T′/2H phases. However, synthesizing large-area, high-quality MoTe2 remains challenging. The complicated design of gas-phase reactant transport and reaction for chemical vapor deposition or tellurization is nontrivial because of the weak bonding energy between Mo and Te. This study reports a new method for depositing MoTe2 that entails using physical vapor deposition followed by a postannealing process in a Te-free atmosphere. Both Mo and Te are physically deposited onto the substrate by sputtering a MoTe2 target. A composite SiO2 capping layer is designed to prevent Te sublimation during the postannealing process. The postannealing process facilitates 1T′-to-2H phase transition and solid-phase crystallization, leading to the formation of high-crystallinity few-layer 2H-MoTe2 with a field-effect mobility of ≈10 cm2 V−1 s−1, the highest among all nonexfoliated 2H-MoTe2 currently reported. Furthermore, 2H-MoS2 and Td-WTe2 can be deposited using similar methods. Requiring no transfer or chemical reaction of metal and chalcogen reactants in the gas phase, the proposed method is potentially a general yet simple approach for depositing a wide variety of large-area, high-quality, 2D layered structures.
KW - molybdenum ditelluride (MoTe)
KW - phase transition
KW - physical vapor deposition
KW - solid-phase crystallization
KW - transition-metal dichalcogenides (TMDs)
UR - http://www.scopus.com/inward/record.url?scp=85018661173&partnerID=8YFLogxK
U2 - 10.1002/admi.201700157
DO - 10.1002/admi.201700157
M3 - 期刊論文
AN - SCOPUS:85018661173
SN - 2196-7350
VL - 4
JO - Advanced Materials Interfaces
JF - Advanced Materials Interfaces
IS - 17
M1 - 1700157
ER -