Nanoscale Raman Characterization of a 2D Semiconductor Lateral Heterostructure Interface.

The nature of the interface in lateral heterostructures of 2D monolayer semiconductors including its composition, size, and heterogeneity critically impacts the functionalities it engenders on the 2D system for next-generation optoelectronics. Here, we use tip-enhanced Raman scattering (TERS) to characterize the interface in a single-layer MoS2/WS2 lateral heterostructure with a spatial resolution of 50 nm. Resonant and nonresonant TERS spectroscopies reveal that the interface is alloyed with a size that varies over an order of magnitude─from 50 to 600 nm─within a single crystallite. Nanoscale imaging of the continuous interfacial evolution of the resonant and nonresonant Raman spectra enables the deconvolution of defect activation, resonant enhancement, and material composition for several vibrational modes in single-layer MoS2, MoxW1-xS2, and WS2. The results demonstrate the capabilities of nanoscale TERS spectroscopy to elucidate macroscopic structure-property relationships in 2D materials and to characterize lateral interfaces of 2D systems on length scales that are imperative for devices.

[1]  Jessica S. Lemos,et al.  Localization of lattice dynamics in low-angle twisted bilayer graphene , 2021, Nature.

[2]  M. Motala,et al.  Direct Optoelectronic Imaging of 2D Semiconductor-3D Metal Buried Interfaces. , 2021, ACS nano.

[3]  T. M. Wallis,et al.  Spatially Resolved Persistent Photoconductivity in MoS2-WS2 Lateral Heterostructures. , 2020, ACS nano.

[4]  K. Novoselov,et al.  Strain and Charge Doping Fingerprints of the Strong Interaction between Monolayer MoS2 and Gold , 2020, The journal of physical chemistry letters.

[5]  B. Hoey.  Michael , 2020, Who Calls the Tune?.

[6]  Y. Saito,et al.  White nanolight source for optical nanoimaging , 2020, Science Advances.

[7]  J. Kysar,et al.  Imaging strain-localized excitons in nanoscale bubbles of monolayer WSe2 at room temperature , 2020, Nature Nanotechnology.

[8]  Yuerui Lu,et al.  Direct Measurement of Folding Angle and Strain Vector in Atomically Thin WS2 Using Second-Harmonic Generation. , 2020, ACS nano.

[9]  T. Taketsugu,et al.  Single-molecule resonance Raman effect in a plasmonic nanocavity , 2020, Nature Nanotechnology.

[10]  B. Ren,et al.  Probing the edge-related properties of atomically thin MoS2 at nanoscale , 2019, Nature Communications.

[11]  E. Pop,et al.  Dry Transfer of van der Waals Crystals to Noble-Metal Surfaces to Enable Characterization of Buried Interfaces. , 2019, ACS applied materials & interfaces.

[12]  D. Jariwala,et al.  Negative refraction inspired polariton lens in van der Waals lateral heterojunctions , 2019, Applied Physics Letters.

[13]  V. A. Apkarian,et al.  Ion-Selective, Atom-Resolved Imaging of a 2D Cu2N Insulator: Field and Current Driven Tip-Enhanced Raman Spectromicroscopy Using a Molecule-Terminated Tip. , 2019, ACS nano.

[14]  V. Dravid,et al.  Spatial Mapping of Hot‐Spots at Lateral Heterogeneities in Monolayer Transition Metal Dichalcogenides , 2019, Advanced materials.

[15]  P. Sahoo,et al.  Probing nano-heterogeneity and aging effects in lateral 2D heterostructures using tip-enhanced photoluminescence , 2019, Optical Materials Express.

[16]  Jeongyong Kim,et al.  Near-field visualization of charge transfer at MoSe2/WSe2 lateral heterojunction , 2019, Optical Materials Express.

[17]  M. Hofmann,et al.  Lateral Two-Dimensional Material Heterojunction Photodetectors with Ultrahigh Speed and Detectivity. , 2019, ACS applied materials & interfaces.

[18]  Xiaoqin Li,et al.  Energy-Resolved Photoconductivity Mapping in a Monolayer-Bilayer WSe2 Lateral Heterostructure. , 2018, Nano letters.

[19]  Ermin Malic,et al.  Exciton physics and device application of two-dimensional transition metal dichalcogenide semiconductors , 2018, npj 2D Materials and Applications.

[20]  T. Zhai,et al.  Self-powered photovoltaic photodetector established on lateral monolayer MoS2-WS2 heterostructures , 2018, Nano Energy.

[21]  Chunlan Wang,et al.  Recent Advances in Optoelectronic Devices Based on 2D Materials and Their Heterostructures , 2018, Advanced Optical Materials.

[22]  M. S. Jeong,et al.  Unveiling Defect-Related Raman Mode of Monolayer WS2 via Tip-Enhanced Resonance Raman Scattering. , 2018, ACS nano.

[23]  A. Pan,et al.  Band Alignment Engineering in Two-Dimensional Lateral Heterostructures. , 2018, Journal of the American Chemical Society.

[24]  Calvin,et al.  Interface excitons at lateral heterojunctions in monolayer semiconductors , 2018, Physical Review B.

[25]  M. Chaigneau,et al.  In situ topographical chemical and electrical imaging of carboxyl graphene oxide at the nanoscale , 2018, Nature Communications.

[26]  Jeongyong Kim,et al.  Composition-Tunable Synthesis of Large-Scale Mo1- xW xS2 Alloys with Enhanced Photoluminescence. , 2018, ACS nano.

[27]  Christian Schneider,et al.  Two-dimensional semiconductors in the regime of strong light-matter coupling , 2018, Nature Communications.

[28]  Lain‐Jong Li,et al.  Self‐Aligned and Scalable Growth of Monolayer WSe2–MoS2 Lateral Heterojunctions , 2018 .

[29]  Y. Ang,et al.  Universal Scaling Laws in Schottky Heterostructures Based on Two-Dimensional Materials. , 2018, Physical review letters.

[30]  R. Hamers,et al.  Nanoscale Surface Photovoltage Mapping of 2D Materials and Heterostructures by Illuminated Kelvin Probe Force Microscopy , 2018 .

[31]  Gerhard Klimeck,et al.  Dramatic Impact of Dimensionality on the Electrostatics of P-N Junctions and Its Sensing and Switching Applications , 2018, IEEE Transactions on Nanotechnology.

[32]  J. Lou,et al.  Quantum plasmonic hot-electron injection in lateral WSe2/MoSe2 heterostructures , 2017, Physical Review B.

[33]  P. Sahoo,et al.  Nano-optical imaging of monolayer MoSe2-WSe2 lateral heterostructure with subwavelength domains , 2017, Journal of Vacuum Science & Technology A.

[34]  Jun Luo,et al.  Robust epitaxial growth of two-dimensional heterostructures, multiheterostructures, and superlattices , 2017, Science.

[35]  Mark A. Marsalis,et al.  Sub-nanometre channels embedded in two-dimensional materials. , 2017, Nature materials.

[36]  M. Raschke,et al.  Radiative control of dark excitons at room temperature by nano-optical antenna-tip Purcell effect , 2017, Nature Nanotechnology.

[37]  M. Molas,et al.  Raman scattering excitation spectroscopy of monolayer WS2 , 2017, Scientific Reports.

[38]  P. Schuck,et al.  The important role of water in growth of monolayer transition metal dichalcogenides , 2017 .

[39]  Xiaohong Yan,et al.  Two dimensional WS2 lateral heterojunctions by strain modulation , 2016 .

[40]  J. Crain,et al.  Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy. , 2016, Nanoscale.

[41]  Jijun Zhao,et al.  Band alignment of two-dimensional lateral heterostructures , 2016, 1603.09447.

[42]  J. Shan,et al.  Photonics and optoelectronics of 2D semiconductor transition metal dichalcogenides , 2016, Nature Photonics.

[43]  A. Hirata,et al.  Chemical Vapor Deposition of Monolayer Mo1−xWxS2 Crystals with Tunable Band Gaps , 2016, Scientific Reports.

[44]  Zafer Mutlu,et al.  Fundamentals of lateral and vertical heterojunctions of atomically thin materials. , 2016, Nanoscale.

[45]  Jianbin Xu,et al.  Lateral Built‐In Potential of Monolayer MoS2–WS2 In‐Plane Heterostructures by a Shortcut Growth Strategy , 2015, Advanced materials.

[46]  Jinlong Yang,et al.  Distinguishing adjacent molecules on a surface using plasmon-enhanced Raman scattering. , 2015, Nature nanotechnology.

[47]  Xi Wan,et al.  Electronic Properties of MoS2-WS2 Heterostructures Synthesized with Two-Step Lateral Epitaxial Strategy. , 2015, ACS nano.

[48]  Sefaattin Tongay,et al.  Visualizing nanoscale excitonic relaxation properties of disordered edges and grain boundaries in monolayer molybdenum disulfide , 2015, Nature Communications.

[49]  Jr-hau He,et al.  Epitaxial growth of a monolayer WSe2-MoS2 lateral p-n junction with an atomically sharp interface , 2015, Science.

[50]  S. Karmalkar,et al.  Analytical theory of the space-charge region of lateral p-n junctions in nanofilms , 2015 .

[51]  C. Yuan,et al.  Influences of carrier gas flow rate on the morphologies of MoS2 flakes , 2015 .

[52]  Wei Shi,et al.  Phonon and Raman scattering of two-dimensional transition metal dichalcogenides from monolayer, multilayer to bulk material. , 2015, Chemical Society reviews.

[53]  M. Pimenta,et al.  Comparative study of Raman spectroscopy in graphene and MoS2-type transition metal dichalcogenides. , 2015, Accounts of chemical research.

[54]  Kuan-Hua Huang,et al.  Synthesis of lateral heterostructures of semiconducting atomic layers. , 2015, Nano letters.

[55]  Wang Yao,et al.  Lateral heterojunctions within monolayer MoSe2-WSe2 semiconductors. , 2014, Nature materials.

[56]  A. Wysmołek,et al.  Resonant Raman scattering in MoS2—From bulk to monolayer , 2014 .

[57]  Hui Zhao,et al.  Transient absorption microscopy of monolayer and bulk WSe2. , 2014, ACS nano.

[58]  Yiming Zhu,et al.  Composition-dependent Raman modes of Mo(1-x)W(x)S2 monolayer alloys. , 2014, Nanoscale.

[59]  J. L. Yang,et al.  Chemical mapping of a single molecule by plasmon-enhanced Raman scattering , 2013, Nature.

[60]  Jean-Christophe Charlier,et al.  Identification of individual and few layers of WS2 using Raman Spectroscopy , 2013, Scientific Reports.

[61]  Dong Wang,et al.  Tunable band gap photoluminescence from atomically thin transition-metal dichalcogenide alloys. , 2013, ACS nano.

[62]  M. Raschke,et al.  Nano-optical imaging and spectroscopy of order, phases, and domains in complex solids , 2012 .

[63]  L. Wirtz,et al.  Phonons in single-layer and few-layer MoS2 , 2011 .

[64]  Ado Jorio,et al.  Raman Spectroscopy in Graphene Related Systems , 2011 .

[65]  M. Dresselhaus,et al.  Quantum Description of Raman Scattering , 2011 .

[66]  A. Wieck,et al.  Depletion characteristics of two-dimensional lateral p‐n-junctions , 2005 .

[67]  Pedro Miguel Figueiredo Amaral.  DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING , 2023 .

[68]  M. Raschke,et al.  Supporting Information to: Hybrid Tip-Enhanced Nanospectroscopy and Nanoimaging of Monolayer WSe2 with Local Strain Control , 2016 .