Layer dependence of the electronic band alignment of few-layer MoS2 on SiO2 measured using photoemission electron microscopy

被引:42
作者
Berg, Morgann [1 ]
Keyshar, Kunttal [2 ]
Bilgin, Ismail [3 ,4 ]
Liu, Fangze [3 ,4 ]
Yamaguchi, Hisato [4 ]
Vajtai, Robert [2 ]
Chan, Calvin [1 ]
Gupta, Gautam [4 ]
Kar, Swastik [3 ]
Ajayan, Pulickel [2 ]
Ohta, Taisuke [1 ]
Mohite, Aditya D. [4 ]
机构
[1] Sandia Natl Labs, Albuquerque, NM 87185 USA
[2] Rice Univ, Dept Mat Sci & Nanoengn, Houston, TX 77005 USA
[3] Northeastern Univ, Dept Phys, Boston, MA 02115 USA
[4] Los Alamos Natl Lab, Los Alamos, NM 87545 USA
基金
美国国家科学基金会;
关键词
DER-WAALS EPITAXY; MOLYBDENUM-DISULFIDE; WORK-FUNCTION; BILAYER MOS2; THIN-FILMS; INTEGRATED-CIRCUITS; PHOTOLUMINESCENCE; HETEROSTRUCTURES; HETEROJUNCTIONS; LUMINESCENCE;
D O I
10.1103/PhysRevB.95.235406
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Tailoring band alignment layer-by-layer using heterojunctions of two-dimensional (2D) semiconductors is an attractive prospect for producing next-generation electronic and optoelectronic devices that are ultrathin, flexible, and efficient. The 2D layers of transition metal dichalcogenides (TMDs) in laboratory devices have already shown favorable characteristics for electronic and optoelectronic applications. Despite these strides, a systematic understanding of how band alignment evolves from monolayer to multilayer structures is still lacking in experimental studies, which hinders development of novel devices based on TMDs. Here, we report on the local band alignment of monolayer, bilayer, and trilayer MoS2 on a 285-nm-thick SiO2 substrate using an approach to probe the occupied electronic states based on photoemission electron microscopy and deep-ultraviolet light. Local measurements of the vacuum level and the valence band edge at the Brillouin zone center show that the addition of layers to monolayer MoS2 increases the relative work function and pushes the valence band edge toward the vacuum level. We also deduced n-type doping of few-layer MoS2 and type-I band alignment across monolayer-to-bilayer and bilayer-to-trilayer lateral junctions. Conducted in isolation from environmental effects owing to the vacuum condition of the measurement and an insulating SiO2 substrate, this study shows a metrology to uncover electronic properties intrinsic to MoS2 semiconducting layers and emerging 2D crystals alike.
引用
收藏
页数:9
相关论文
共 78 条
[1]   Near-unity photoluminescence quantum yield in MoS2 [J].
Amani, Matin ;
Lien, Der-Hsien ;
Kiriya, Daisuke ;
Xiao, Jun ;
Azcatl, Angelica ;
Noh, Jiyoung ;
Madhvapathy, Surabhi R. ;
Addou, Rafik ;
Santosh, K. C. ;
Dubey, Madan ;
Cho, Kyeongjae ;
Wallace, Robert M. ;
Lee, Si-Chen ;
He, Jr-Hau ;
Ager, Joel W., III ;
Zhang, Xiang ;
Yablonovitch, Eli ;
Javey, Ali .
SCIENCE, 2015, 350 (6264) :1065-1068
[2]   Realization and electrical characterization of ultrathin crystals of layered transition-metal dichalcogenides [J].
Ayari, Anthony ;
Cobas, Enrique ;
Ogundadegbe, Ololade ;
Fuhrer, Michael S. .
JOURNAL OF APPLIED PHYSICS, 2007, 101 (01)
[3]   Visibility of dichalcogenide nanolayers [J].
Benameur, M. M. ;
Radisavljevic, B. ;
Heron, J. S. ;
Sahoo, S. ;
Berger, H. ;
Kis, A. .
NANOTECHNOLOGY, 2011, 22 (12)
[4]   Extraordinary Sunlight Absorption and One Nanometer Thick Photovoltaics Using Two-Dimensional Monolayer Materials [J].
Bernardi, Marco ;
Palummo, Maurizia ;
Grossman, Jeffrey C. .
NANO LETTERS, 2013, 13 (08) :3664-3670
[5]   Chemical Vapor Deposition Synthesized Atomically Thin Molybdenum Disulfide with Optoelectronic-Grade Crystalline Quality [J].
Bilgin, Ismail ;
Liu, Fangze ;
Vargas, Anthony ;
Winchester, Andrew ;
Man, Michael K. L. ;
Upmanyu, Moneesh ;
Dani, Keshav M. ;
Gupta, Gautam ;
Talapatra, Saikat ;
Mohite, Aditya D. ;
Kar, Swastik .
ACS NANO, 2015, 9 (09) :8822-8832
[6]   Making graphene visible [J].
Blake, P. ;
Hill, E. W. ;
Castro Neto, A. H. ;
Novoselov, K. S. ;
Jiang, D. ;
Yang, R. ;
Booth, T. J. ;
Geim, A. K. .
APPLIED PHYSICS LETTERS, 2007, 91 (06)
[7]   Single-layer MoS2 on Au(111): Band gap renormalization and substrate interaction [J].
Bruix, Albert ;
Miwa, Jill A. ;
Hauptmann, Nadine ;
Wegner, Daniel ;
Ulstrup, Soren ;
Gronborg, Signe S. ;
Sanders, Charlotte E. ;
Dendzik, Maciej ;
Cabo, Antonija Grubisic ;
Bianchi, Marco ;
Lauritsen, Jeppe V. ;
Khajetoorians, Alexander A. ;
Hammer, Bjork ;
Hofmann, Philip .
PHYSICAL REVIEW B, 2016, 93 (16)
[8]   Electric-Field Screening in Atomically Thin Layers of MoS2: the Role of Interlayer Coupling [J].
Castellanos-Gomez, Andres ;
Cappelluti, Emmanuele ;
Roldan, Rafael ;
Agrait, Nicolas ;
Guinea, Francisco ;
Rubio-Bollinger, Gabino .
ADVANCED MATERIALS, 2013, 25 (06) :899-903
[9]   Thin films of fullerene-like MoS2 nanoparticles with ultra-low friction and wear [J].
Chhowalla, M ;
Amaratunga, GAJ .
NATURE, 2000, 407 (6801) :164-167
[10]   Layer-number-dependent work function of MoS2 nanoflakes [J].
Choi, SooHo ;
Shaolin, Zhang ;
Yang, Woochul .
JOURNAL OF THE KOREAN PHYSICAL SOCIETY, 2014, 64 (10) :1550-1555