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Pham PV, Mai TH, Dash SP, Biju V, Chueh YL, Jariwala D, Tung V. Transfer of 2D Films: From Imperfection to Perfection. ACS NANO 2024. [PMID: 38810109 DOI: 10.1021/acsnano.4c00590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Atomically thin 2D films and their van der Waals heterostructures have demonstrated immense potential for breakthroughs and innovations in science and technology. Integrating 2D films into electronics and optoelectronics devices and their applications in electronics and optoelectronics can lead to improve device efficiencies and tunability. Consequently, there has been steady progress in large-area 2D films for both front- and back-end technologies, with a keen interest in optimizing different growth and synthetic techniques. Parallelly, a significant amount of attention has been directed toward efficient transfer techniques of 2D films on different substrates. Current methods for synthesizing 2D films often involve high-temperature synthesis, precursors, and growth stimulants with highly chemical reactivity. This limitation hinders the widespread applications of 2D films. As a result, reports concerning transfer strategies of 2D films from bare substrates to target substrates have proliferated, showcasing varying degrees of cleanliness, surface damage, and material uniformity. This review aims to evaluate, discuss, and provide an overview of the most advanced transfer methods to date, encompassing wet, dry, and quasi-dry transfer methods. The processes, mechanisms, and pros and cons of each transfer method are critically summarized. Furthermore, we discuss the feasibility of these 2D film transfer methods, concerning their applications in devices and various technology platforms.
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Affiliation(s)
- Phuong V Pham
- Department of Physics, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - The-Hung Mai
- Department of Physics, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Saroj P Dash
- Department of Microtechnology and Nanoscience, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Vasudevanpillai Biju
- Research Institute for Electronic Science, Hokkaido University, Hokkaido 001-0020, Japan
| | - Yu-Lun Chueh
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Vincent Tung
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
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2
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Bera A, Kundu B, Pal AJ. Does an intrinsic strain contribute to the effect of quantum confinement phenomenon? An alloyed transition metal dichalcogenide series, Mo(S 1-xSe x) 2 as a case study. NANOSCALE 2024; 16:9966-9974. [PMID: 38695085 DOI: 10.1039/d3nr06107h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2024]
Abstract
It is well known that the bandgap of 2D transition metal dichalcogenides (TMDs) in the quantum confinement regime increases with a decrease in the number of layers. In this work, we show the effect of lattice strain on the dependence of the gap. We have designed an ideal system in the form of common-cationic alloyed-TMDs, Mo(S1-xSex)2, for such studies. With a large difference between the ionic radii of the two chalcogens, the nanoflakes of the alloys possessed a lattice strain and have been found to yield a lower bandgap than those of both the end-members, MoS2 and MoSe2. More importantly, the dependence of the bandgap on the layer number in the nanoflakes of the alloys turned out to be steeper than in conventional binary TMDs. The experimental results imply that the lattice strain in 2D semiconductors has contributed to the effect of the quantum confinement phenomenon in addition to decreasing the bandgap, the latter being earlier predicted from a theoretical model. We have derived the electronic bandgap and the band-edge energies of the series of alloyed-TMDs in their nanoflake forms and the dependences on the number of layers from the density of states (DOS), as obtained from scanning tunneling spectroscopy (STS) recorded in a scanning tunneling microscope (STM) in an extremely localized manner.
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Affiliation(s)
- Arpan Bera
- School of Physical Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.
| | - Biswajit Kundu
- School of Physical Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.
| | - Amlan J Pal
- School of Physical Sciences, Indian Association for the Cultivation of Science, Kolkata 700032, India.
- UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India
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Liu H, Zhao J, Ly TH. Clean Transfer of Two-Dimensional Materials: A Comprehensive Review. ACS NANO 2024; 18:11573-11597. [PMID: 38655635 DOI: 10.1021/acsnano.4c01000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The growth of two-dimensional (2D) materials through chemical vapor deposition (CVD) has sparked a growing interest among both the industrial and academic communities. The interest stems from several key advantages associated with CVD, including high yield, high quality, and high tunability. In order to harness the application potentials of 2D materials, it is often necessary to transfer them from their growth substrates to their desired target substrates. However, conventional transfer methods introduce contamination that can adversely affect the quality and properties of the transferred 2D materials, thus limiting their overall application performance. This review presents a comprehensive summary of the current clean transfer methods for 2D materials with a specific focus on the understanding of interaction between supporting layers and 2D materials. The review encompasses various aspects, including clean transfer methods, post-transfer cleaning techniques, and cleanliness assessment. Furthermore, it analyzes and compares the advances and limitations of these clean transfer techniques. Finally, the review highlights the primary challenges associated with current clean transfer methods and provides an outlook on future prospects.
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Affiliation(s)
- Haijun Liu
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong 999077, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong 999077, China
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Song S, Rahaman M, Jariwala D. Can 2D Semiconductors Be Game-Changers for Nanoelectronics and Photonics? ACS NANO 2024; 18:10955-10978. [PMID: 38625032 DOI: 10.1021/acsnano.3c12938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
2D semiconductors have interesting physical and chemical attributes that have led them to become one of the most intensely investigated semiconductor families in recent history. They may play a crucial role in the next technological revolution in electronics as well as optoelectronics or photonics. In this Perspective, we explore the fundamental principles and significant advancements in electronic and photonic devices comprising 2D semiconductors. We focus on strategies aimed at enhancing the performance of conventional devices and exploiting important properties of 2D semiconductors that allow fundamentally interesting device functionalities for future applications. Approaches for the realization of emerging logic transistors and memory devices as well as photovoltaics, photodetectors, electro-optical modulators, and nonlinear optics based on 2D semiconductors are discussed. We also provide a forward-looking perspective on critical remaining challenges and opportunities for basic science and technology level applications of 2D semiconductors.
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Affiliation(s)
- Seunguk Song
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Mahfujur Rahaman
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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Zhang J, Xiao Y, Li K, Chen Y, Liu S, Luo W, Liu X, Liu S, Wang Y, Li SY, Pan A. Microscopy aided detection of the self-intercalation mechanism and in situ electronic properties in chromium selenide. NANOSCALE 2024; 16:8028-8035. [PMID: 38546273 DOI: 10.1039/d4nr00048j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Two-dimensional (2D) chromium-based self-intercalated materials Cr1+nX2 (0 ≤ n ≤ 1, X = S, Se, Te) have attracted much attention because of their tunable magnetism with good environmental stability. Intriguingly, the magnetic and electrical properties of the materials can be effectively tuned by altering the coverage and spatial arrangement of the intercalated Cr (ic-Cr) within the van der Waals gap, contributing to different stoichiometries. Several different Cr1+nX2 systems have been widely investigated recently; however, those with the same stoichiometric ratio (such as Cr1.25Te2) were reported to exhibit disparate magnetic properties, which still lacks explanation. Therefore, a systematic in situ study of the mechanisms with microscopy techniques is in high demand to look into the origin of these discrepancies. Herein, 2D self-intercalated Cr1+nSe2 nanoflakes were synthesized as a platform to conduct the characterization. Combining scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM), we studied in depth the microscopic structure and local electronic properties of the Cr1+nSe2 nanoflakes. The self-intercalation mechanism of ic-Cr and local stoichiometric-ratio variation in a Cr1+nSe2 ultrathin nanoflake is clearly detected at the nanometer scale. Scanning tunneling spectroscopy (STS) measurements indicate that Cr1.5Se2/Cr2Se2 and Cr1.25Se2 exhibit conductive and semiconductive behaviors, respectively. The STM tip manipulation method is further applied to manipulate the microstructure of Cr1+nSe2, which successfully produces clean zigzag-type boundaries. Our systematic microscopy study paves the way for the in-depth study of the magnetic mechanism of 2D self-intercalated magnets at the nano/micro scale and the development of new magnetic and spintronic devices.
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Affiliation(s)
- Jinding Zhang
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Yulong Xiao
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Kaihui Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Ying Chen
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Songlong Liu
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Wenjie Luo
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Xueying Liu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Shiying Liu
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
| | - Yiliu Wang
- School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China
| | - Si-Yu Li
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
- Greater Bay Area Institute for Innovation, Hunan University, Guangzhou 511300, People's Republic of China
| | - Anlian Pan
- Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan Institute of Optoelectronic Integration and College of Materials Science and Engineering, Hunan University, Changsha 410082, People's Republic of China.
- School of Physics and Electronics, Hunan Normal University, Changsha 410081, People's Republic of China.
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Kokkiligadda S, Mondal A, Um SH, Park SH, Biswas C. Observation of Ultrahigh Photoconductivity in DNA-MoS 2 Nano-Biocomposite. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2400124. [PMID: 38488277 DOI: 10.1002/adma.202400124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 03/12/2024] [Indexed: 05/26/2024]
Abstract
A nano-biocomposite film with ultrahigh photoconductivity remains elusive and critical for bio-optoelectronic applications. A uniform, well-connected, high-concentration nanomaterial network in the biological matrix remains challenging to achieve high photoconductivity. Wafer-scale continuous nano-biocomposite film without surface deformations and cracks plays another major obstacle. Here ultrahigh photoconductivity is observed in deoxyribonucleic acid-molybdenum disulfide (DNA-MoS2) nano-biocomposite film by incorporating a high-concentration, well-percolated, and uniform MoS2 network in the ss-DNA matrix. This is achieved by utilizing DNA-MoS2 hydrogel formation, which results in crack-free, wafer-scale DNA-MoS2 nano-biocomposite films. Ultra-high photocurrent (5.5 mA at 1 V) with a record-high on/off ratio (1.3 × 106) is observed, five orders of magnitude higher than conventional biomaterials (≈101) reported so far. The incorporation of the Wely semimetal (Bismuth) as an electrical contact exhibits ultrahigh photoresponsivity (2.6 × 105 A W-1). Such high photoconductivity in DNA-MoS2 nano-biocomposite could bridge the gap between biology, electronics, and optics for innovative biomedicine, bioengineering, and neuroscience applications.
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Affiliation(s)
- Samanth Kokkiligadda
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Ashok Mondal
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
- Department of Energy Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Soong Ho Um
- School of Chemical Engineering, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Sung Ha Park
- Department of Physics, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Chandan Biswas
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
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Chen J, Liu L, Chen H, Xu N, Deng S. Controlled Preparation of High Quality Bubble-Free and Uniform Conducting Interfaces of Vertical van der Waals Heterostructures of Arrays. ACS APPLIED MATERIALS & INTERFACES 2024; 16:10877-10885. [PMID: 38360529 DOI: 10.1021/acsami.3c16128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Sharp and clean interfaces of van der Waals (vdW) heterostructures are highly demanded in two-dimensional (2D) materials-based devices. However, current assembly methods usually cause interfacial bubbles and wrinkles, hindering carrier interlayer transport. The preparation of a large-scale vdW heterostructure with a bubble-free interface is still a challenge. Although many efforts have been made to eliminate bubbles, the evolution processes of the interfacial bubbles are rarely studied. Here, the interface bubble formation and evolution of the transferred 2D materials and their vdW heterostructure are systemically studied by the atomic force microscopy (AFM) technique and high-resolution surface current mapping. A thermal annealing procedure is developed to reduce the number of bubbles and to improve the quality of interfaces. In addition, influences of the interface residues and nanosteps on bubble evolution are also discussed. Further, we develop the polystyrene (PS)-mediated polydimethylsiloxane (PDMS) transfer technique to realize the high-quality transfer of heterostructure arrays. Finally, high-resolution surface current mapping results confirm that we can now produce highly uniform electrical conduction interfaces of heterojunctions. This study provides guidance for assembling high quality interfaces and paves the way for production of bubble-free heterostructure-based electronic devices with high performance and good uniformity.
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Affiliation(s)
- Jianwei Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Liwei Liu
- Frontier Institute of Chip and System, Fudan University, Shanghai 200433, China
| | - Huanjun Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Ningsheng Xu
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Shaozhi Deng
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou 510275, China
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Kim J, Rhee D, Jung M, Cheon GJ, Kim K, Kim JH, Park JY, Yoon J, Lim DU, Cho JH, Kim IS, Son D, Jariwala D, Kang J. Defect-Engineered Semiconducting van der Waals Thin Film at Metal-Semiconductor Interface of Field-Effect Transistors. ACS NANO 2024; 18:1073-1083. [PMID: 38100089 DOI: 10.1021/acsnano.3c10453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
The significance of metal-semiconductor interfaces and their impact on electronic device performance have gained increasing attention, with a particular focus on investigating the contact metal. However, another avenue of exploration involves substituting the contact metal at the metal-semiconductor interface of field-effect transistors with semiconducting layers to introduce additional functionalities to the devices. Here, a scalable approach for fabricating metal-oxide-semiconductor (channel)-semiconductor (interfacial layer) field-effect transistors is proposed by utilizing solution-processed semiconductors, specifically semiconducting single-walled carbon nanotubes and molybdenum disulfide, as the channel and interfacial semiconducting layers, respectively. The work function of the interfacial MoS2 is modulated by controlling the sulfur vacancy concentration through chemical treatment, which results in distinctive energy band alignments within a single device configuration. The resulting band alignments lead to multiple functionalities, including multivalued transistor characteristics and multibit nonvolatile memory (NVM) behavior. Moreover, leveraging the stable NVM properties, we demonstrate artificial synaptic devices with 88.9% accuracy of MNIST image recognition.
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Affiliation(s)
- Jihyun Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Dongjoon Rhee
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Myeongjin Jung
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Gang Jin Cheon
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Kangsan Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Jae Hyung Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Ji Yun Park
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Jiyong Yoon
- Department of Electrical and Computer Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Dong Un Lim
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Jeong Ho Cho
- Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - In Soo Kim
- Nanophotonics Research Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- KIST-SKKU Carbon-Neutral Research Center, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Donghee Son
- Department of Electrical and Computer Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Nanophotonics Research Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- KIST-SKKU Carbon-Neutral Research Center, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Joohoon Kang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Nanophotonics Research Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- KIST-SKKU Carbon-Neutral Research Center, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
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Wang X, Hu Y, Kim SY, Addou R, Cho K, Wallace RM. Origins of Fermi Level Pinning for Ni and Ag Metal Contacts on Tungsten Dichalcogenides. ACS NANO 2023; 17:20353-20365. [PMID: 37788682 DOI: 10.1021/acsnano.3c06494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Tungsten transition metal dichalcogenides (W-TMDs) are intriguing due to their properties and potential for application in next-generation electronic devices. However, strong Fermi level (EF) pinning manifests at the metal/W-TMD interfaces, which could tremendously restrain the carrier injection into the channel. In this work, we illustrate the origins of EF pinning for Ni and Ag contacts on W-TMDs by considering interface chemistry, band alignment, impurities, and imperfections of W-TMDs, contact metal adsorption mechanism, and the resultant electronic structure. We conclude that the origins of EF pinning at a covalent contact metal/W-TMD interface, such as Ni/W-TMDs, can be attributed to defects, impurities, and interface reaction products. In contrast, for a van der Waals contact metal/TMD system such as Ag/W-TMDs, the primary factor responsible for EF pinning is the electronic modification of the TMDs resulting from the defects and impurities with the minor impact of metal-induced gap states. The potential strategies for carefully engineering the metal deposition approach are also discussed. This work unveils the origins of EF pinning at metal/TMD interfaces experimentally and theoretically and provides guidance on further enhancing and improving the device performance.
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Affiliation(s)
- Xinglu Wang
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Yaoqiao Hu
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Seong Yeoul Kim
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Rafik Addou
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Kyeongjae Cho
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Robert M Wallace
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States
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