Hopping transport through defect-induced localized states in molybdenum disulphide

被引：1030

作者：

Qiu, Hao ^{[1
]}

Xu, Tao ^{[2
]}

Wang, Zilu ^{[3
]}

Ren, Wei ^{[4
]}

Nan, Haiyan ^{[3
]}

Ni, Zhenhua ^{[3
]}

Chen, Qian ^{[3
]}

Yuan, Shijun ^{[3
]}

Miao, Feng ^{[5
]}

Song, Fengqi ^{[5
]}

Long, Gen ^{[1
]}

Shi, Yi ^{[1
]}

Sun, Litao ^{[2
]}

Wang, Jinlan ^{[3
]}

Wang, Xinran ^{[1
]}

机构：

[1] Nanjing Univ, Sch Elect Sci & Engn, Natl Lab Solid State Microstruct, Natl Ctr Microstruct & Quantum Manipulat, Nanjing 210093, Jiangsu, Peoples R China

[2] Southeast Univ, Minist Educ, Key Lab MEMS, SEU FEI Nano Pico Ctr, Nanjing 210096, Jiangsu, Peoples R China

[3] Southeast Univ, Dept Phys, Nanjing 211189, Jiangsu, Peoples R China

[4] Shanghai Univ, Dept Phys, Shanghai 200444, Peoples R China

[5] Nanjing Univ, Sch Phys, Nanjing 210093, Jiangsu, Peoples R China

来源：

NATURE COMMUNICATIONS | 2013年 / 4卷

基金：

中国国家自然科学基金;

关键词：

MOS2; MOBILITY; TRANSISTORS; LAYERS;

D O I：

10.1038/ncomms3642

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Molybdenum disulphide is a novel two-dimensional semiconductor with potential applications in electronic and optoelectronic devices. However, the nature of charge transport in back-gated devices still remains elusive as they show much lower mobility than theoretical calculations and native n-type doping. Here we report a study of transport in few-layer molybdenum disulphide, together with transmission electron microscopy and density functional theory. We provide direct evidence that sulphur vacancies exist in molybdenum disulphide, introducing localized donor states inside the bandgap. Under low carrier densities, the transport exhibits nearest-neighbour hopping at high temperatures and variable-range hopping at low temperatures, which can be well explained under Mott formalism. We suggest that the low-carrier-density transport is dominated by hopping via these localized gap states. Our study reveals the important role of short-range surface defects in tailoring the properties and device applications of molybdenum disulphide.

引用

页数：6

共 47 条

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