How high is a MoSe2 monolayer?

Abstract Transition metal dichalcogenides (TMDCs) have attracted significant attention for optoelectronic, photovoltaic and photoelectrochemical applications. The properties of TMDCs are highly dependent on the number of stacked atomic layers, which is usually counted post-fabrication, using a combination of optical methods and atomic force microscopy height measurements. Here, we use photoluminescence spectroscopy, Raman spectroscopy, and three different AFM methods to demonstrate significant discrepancies in height measurements of exfoliated MoSe2 flakes on SiO2 depending on the method used. We also highlight the often overlooked effect that electrostatic forces can be misleading when measuring the height of a MoSe2 flake using AFM.

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Analysis of Airborne Contamination on Transition Metal Dichalcogenides with Atomic Force Microscopy Revealing That Sulfur Is the Preferred Chalcogen Atom for Devices Made in Ambient Conditions

ACS Applied Nano Materials ◽

10.1021/acsanm.9b00526 ◽

2019 ◽

Vol 2 (5) ◽

pp. 2593-2598 ◽

Cited By ~ 2

Author(s):

Korbinian Pürckhauer ◽

Dominik Kirpal ◽

Alfred J. Weymouth ◽

Franz J. Giessibl

Keyword(s):

Atomic Force Microscopy ◽

Transition Metal ◽

Transition Metal Dichalcogenides ◽

Chalcogen Atom ◽

Ambient Conditions ◽

Force Microscopy ◽

Atomic Force ◽

Airborne Contamination ◽

Metal Dichalcogenides ◽

Made In

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Conductive Atomic Force Microscopy of Semiconducting Transition Metal Dichalcogenides and Heterostructures

Nanomaterials ◽

10.3390/nano10040803 ◽

2020 ◽

Vol 10 (4) ◽

pp. 803 ◽

Cited By ~ 1

Author(s):

Filippo Giannazzo ◽

Emanuela Schilirò ◽

Giuseppe Greco ◽

Fabrizio Roccaforte

Keyword(s):

Atomic Force Microscopy ◽

Transition Metal ◽

Grain Boundaries ◽

Schottky Barrier ◽

Transition Metal Dichalcogenides ◽

Device Fabrication ◽

Conductive Atomic Force Microscopy ◽

Force Microscopy ◽

Atomic Force ◽

Metal Dichalcogenides

Semiconducting transition metal dichalcogenides (TMDs) are promising materials for future electronic and optoelectronic applications. However, their electronic properties are strongly affected by peculiar nanoscale defects/inhomogeneities (point or complex defects, thickness fluctuations, grain boundaries, etc.), which are intrinsic of these materials or introduced during device fabrication processes. This paper reviews recent applications of conductive atomic force microscopy (C-AFM) to the investigation of nanoscale transport properties in TMDs, discussing the implications of the local phenomena in the overall behavior of TMD-based devices. Nanoscale resolution current spectroscopy and mapping by C-AFM provided information on the Schottky barrier uniformity and shed light on the mechanisms responsible for the Fermi level pinning commonly observed at metal/TMD interfaces. Methods for nanoscale tailoring of the Schottky barrier in MoS2 for the realization of ambipolar transistors are also illustrated. Experiments on local conductivity mapping in monolayer MoS2 grown by chemical vapor deposition (CVD) on SiO2 substrates are discussed, providing a direct evidence of the resistance associated to the grain boundaries (GBs) between MoS2 domains. Finally, C-AFM provided an insight into the current transport phenomena in TMD-based heterostructures, including lateral heterojunctions observed within MoxW1–xSe2 alloys, and vertical heterostructures made by van der Waals stacking of different TMDs (e.g., MoS2/WSe2) or by CVD growth of TMDs on bulk semiconductors.

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Characterization of single transition metal oxide nanorods by combining atomic force microscopy and polarized micro-Raman spectroscopy

Chemical Physics Letters ◽

10.1016/j.cplett.2011.08.039 ◽

2011 ◽

Vol 514 (1-3) ◽

pp. 128-133 ◽

Cited By ~ 7

Author(s):

Samar Najjar ◽

David Talaga ◽

Yannick Coffinier ◽

Sabine Szunerits ◽

Rabah Boukherroub ◽

...

Keyword(s):

Raman Spectroscopy ◽

Atomic Force Microscopy ◽

Transition Metal ◽

Metal Oxide ◽

Force Microscopy ◽

Micro Raman Spectroscopy ◽

Atomic Force ◽

Oxide Nanorods ◽

Single Transition

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Electrostatic Forces on the Surface of Metals as Measured by Atomic Force Microscopy

Journal of Long-Term Effects of Medical Implants ◽

10.1615/.v10.i12.100 ◽

2000 ◽

Vol 10 (1-2) ◽

pp. 15

Author(s):

Eugene Sprague ◽

Julio C. Palmaz ◽

Cristina Simon ◽

Aaron Watson

Keyword(s):

Atomic Force Microscopy ◽

Electrostatic Forces ◽

Force Microscopy ◽

Atomic Force

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Exploring Intramolecular Methyl–Methyl Coupling on a Metal Surface for Edge-Extended Graphene Nanoribbons

Organic Materials ◽

10.1055/s-0041-1726295 ◽

2021 ◽

Vol 03 (02) ◽

pp. 128-133

Author(s):

Zijie Qiu ◽

Qiang Sun ◽

Shiyong Wang ◽

Gabriela Borin Barin ◽

Bastian Dumslaff ◽

...

Keyword(s):

Raman Spectroscopy ◽

Atomic Force Microscopy ◽

High Resolution ◽

Graphene Nanoribbons ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Methyl Methyl ◽

Atomic Force ◽

Edge Extension

Intramolecular methyl–methyl coupling on Au (111) is explored as a new on-surface protocol for edge extension in graphene nanoribbons (GNRs). Characterized by high-resolution scanning tunneling microscopy, noncontact atomic force microscopy, and Raman spectroscopy, the methyl–methyl coupling is proven to indeed proceed at the armchair edges of the GNRs, forming six-membered rings with sp3- or sp2-hybridized carbons.

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