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Kim S, Jeon Y, Lee EK, Kim YJ, Kim CH, Yoo H. Light-Triggerable and Gate-Tunable Negative Differential Resistance in Small Molecules Heterojunction. NANO LETTERS 2024; 24:2025-2032. [PMID: 38295356 DOI: 10.1021/acs.nanolett.3c04671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
Negative differential resistance (NDR), a phenomenon in which the current decreases when the applied voltage is increased, is attracting attention as a unique electrical property. Here, we propose a broad spectral photo/gate cotunable channel switching NDR (CS-NDR) device. The proposed CS-NDR device has superior linear gate-tunable NDR behavior and highly reproducible properties compared to the previously reported NDR devices, as the fundamental mechanism of the CS-NDR device is directly related to a charge transport channel switching by the linear increase of the applied drain voltage. We also experimentally demonstrate that the photoinduced NDR behavior of the CS-NDR device was derived from the grain boundaries of dinaphtho[2;3-b:2',3'-f]-thieno[3,2-b]thiophene. Furthermore, this work produces a 9 × 9 CS-NDR device array composed of 81 devices, providing the reproducibility and uniformity of the CS-NDR device. Finally, we successfully demonstrate the detection of text images with 81 CS-NDR devices using the proposed photo/gate cotunable NDR behavior.
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Affiliation(s)
- Seongjae Kim
- SDC Research Group, Department of Electronic Engineering, Gachon University, 1342 Seongnam-daero, Seongnam 13120, Republic of Korea
| | - Yunchae Jeon
- SDC Research Group, Department of Electronic Engineering, Gachon University, 1342 Seongnam-daero, Seongnam 13120, Republic of Korea
| | - Eun Kwang Lee
- Department of Chemical Engineering, Pukyong National University, Busan 48513, Republic of Korea
| | - Yeong Jae Kim
- Ceramic Total Solution Center, Korea Institute of Ceramic Engineering and Technology, Icheon 17303, Republic of Korea
| | - Chang-Hyun Kim
- School of Electrical Engineering and Computer Science, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Hocheon Yoo
- SDC Research Group, Department of Electronic Engineering, Gachon University, 1342 Seongnam-daero, Seongnam 13120, Republic of Korea
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2
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Chang WH, Lu CI, Yang TH, Yang ST, Simbulan KB, Lin CP, Hsieh SH, Chen JH, Li KS, Chen CH, Hou TH, Lu TH, Lan YW. Defect-engineered room temperature negative differential resistance in monolayer MoS 2 transistors. NANOSCALE HORIZONS 2022; 7:1533-1539. [PMID: 36285561 DOI: 10.1039/d2nh00396a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The negative differential resistance (NDR) effect has been widely investigated for the development of various electronic devices. Apart from traditional semiconductor-based devices, two-dimensional (2D) transition metal dichalcogenide (TMD)-based field-effect transistors (FETs) have also recently exhibited NDR behavior in several of their heterostructures. However, to observe NDR in the form of monolayer MoS2, theoretical prediction has revealed that the material should be more profoundly affected by sulfur (S) vacancy defects. In this work, monolayer MoS2 FETs with a specific amount of S-vacancy defects are fabricated using three approaches, namely chemical treatment (KOH solution), physical treatment (electron beam bombardment), and as-grown MoS2. Based on systematic studies on the correlation of the S-vacancies with both the device's electron transport characteristics and spectroscopic analysis, the NDR has been clearly observed in the defect-engineered monolayer MoS2 FETs with an S-vacancy (VS) amount of ∼5 ± 0.5%. Consequently, stable NDR behavior can be observed at room temperature, and its peak-to-valley ratio can also be effectively modulated via the gate electric field and light intensity. Through these results, it is envisioned that more electronic applications based on defect-engineered layered TMDs will emerge in the near future.
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Affiliation(s)
- Wen-Hao Chang
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
| | - Chun-I Lu
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
| | - Tilo H Yang
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
| | - Shu-Ting Yang
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
| | - Kristan Bryan Simbulan
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
- Department of Mathematics and Physics, University of Santo Tomas, Manila 1008, Philippines
| | - Chih-Pin Lin
- Department of Electronics Engineering & Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
| | | | - Jyun-Hong Chen
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 300, Taiwan
| | - Kai-Shin Li
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 300, Taiwan
| | - Chia-Hao Chen
- National Synchrotron Radiation Research Center, Hsinchu 300, Taiwan
- Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Tuo-Hung Hou
- Department of Electronics Engineering & Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Ting-Hua Lu
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
| | - Yann-Wen Lan
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan.
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3
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Pan Y, Liu X, Yang J, Yoo WJ, Sun J. Controlling Carrier Transport in Vertical MoTe 2/MoS 2 van der Waals Heterostructures. ACS APPLIED MATERIALS & INTERFACES 2021; 13:54294-54300. [PMID: 34739218 DOI: 10.1021/acsami.1c16594] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Two-dimensional (2D) transition-metal dichalcogenide (TMDC)-based semiconducting van der Waals (vdW) heterostructures are considered as potential candidates for next-generation nanoelectronics due to their unique and tunable properties. Controlling the carrier type and band alignment in 2D TMDCs and their vdW heterostructures is critical for realizing heterojunctions with the desired performances and functionalities. In this report, controlling the carrier type and band alignment in a vertical MoTe2/MoS2 heterojunction is presented via thickness engineering and surface charge transfer doping. A highly rectifying p-n diode and a nonrectifying n-n junction are obtained with different MoTe2 thicknesses due to their different doping conditions. A vertical tunnel diode is subsequently achieved with a controlled oxygen plasma treatment, which selectively induces degenerate p-type doping to MoTe2, whereas the intrinsic n-type characteristic of MoS2 is maintained during the treatment. These techniques to realize multifunctional diodes are universal and applicable to emerging nanoelectronics based on 2D materials.
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Affiliation(s)
- Yuchuan Pan
- School of Physics and Electronics, Central South University, Changsha 410083, China
| | - Xiaochi Liu
- School of Physics and Electronics, Central South University, Changsha 410083, China
| | - Junqiang Yang
- School of Physics and Electronics, Central South University, Changsha 410083, China
| | - Won Jong Yoo
- SKKU Advanced Institute of Nano-Technology (SAINT), Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jian Sun
- School of Physics and Electronics, Central South University, Changsha 410083, China
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Kim J, Venkatesan A, Kim H, Kim Y, Whang D, Kim G. Improved Contact Resistance by a Single Atomic Layer Tunneling Effect in WS 2 /MoTe 2 Heterostructures. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100102. [PMID: 34105270 PMCID: PMC8188188 DOI: 10.1002/advs.202100102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/01/2021] [Indexed: 06/12/2023]
Abstract
Manipulation of Ohmic contacts in 2D transition metal dichalcogenides for enhancing the transport properties and enabling its application as a practical device has been a long-sought goal. In this study, n-type tungsten disulfide (WS2 ) single atomic layer to improve the Ohmic contacts of the p-type molybdenum ditelluride (MoTe2 ) material is covered. The Ohmic properties, based on the lowering of Schottky barrier height (SBH) owing to the tunneling barrier effect of the WS2 monolayer, are found to be unexpectedly excellent at room temperature and even at 100 K. The improved SBH and contact resistances are 3 meV and 1 MΩ µm, respectively. The reduction in SBH and contact resistance is confirmed with temperature-dependent transport measurements. This study further demonstrates the selective carrier transport across the MoTe2 and WS2 layers by modulating the applied gate voltage. This WS2 /MoTe2 heterostructure exhibits excellent gate control over the currents of both channels (n-type and p-type). The on/off ratios for both the electron and hole channels are calculated as 107 and 106 , respectively, indicating good carrier type modulation by the electric field of the gate electrode. The Ohmic contact resistance using the tunneling of the atomic layer can be applied to heterojunction combinations of various materials.
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Affiliation(s)
- Jihoon Kim
- School of Electronic and Electrical EngineeringSungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - A. Venkatesan
- School of Electronic and Electrical EngineeringSungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Hanul Kim
- Samsung‐SKKU Graphene CentreSungkyunkwan Advanced Institute of Nanotechnology (SAINT)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Yewon Kim
- School of Electronic and Electrical EngineeringSungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Dongmok Whang
- Samsung‐SKKU Graphene CentreSungkyunkwan Advanced Institute of Nanotechnology (SAINT)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
- School of Advanced Materials Science and EngineeringSungkyunkwan University (SKKU)Suwon16419Republic of Korea
| | - Gil‐Ho Kim
- School of Electronic and Electrical EngineeringSungkyunkwan University (SKKU)Suwon16419Republic of Korea
- Samsung‐SKKU Graphene CentreSungkyunkwan Advanced Institute of Nanotechnology (SAINT)Sungkyunkwan University (SKKU)Suwon16419Republic of Korea
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Abraham N, Murali K, Watanabe K, Taniguchi T, Majumdar K. Astability versus Bistability in van der Waals Tunnel Diode for Voltage Controlled Oscillator and Memory Applications. ACS NANO 2020; 14:15678-15687. [PMID: 33091295 DOI: 10.1021/acsnano.0c06630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
van der Waals (vdW) tunnel junctions are attractive because of their atomically sharp interface, gate tunability, and robustness against lattice mismatch between the successive layers. However, the negative differential resistance (NDR) demonstrated in this class of tunnel diodes often exhibits noisy behavior with low peak current density and lacks robustness and repeatability, limiting their practical circuit applications. Here, we propose a strategy of using a 1L-WS2 as an optimum tunnel barrier sandwiched in a broken gap tunnel junction of highly doped black phosphorus (BP) and SnSe2. We achieve high yield tunnel diodes exhibiting highly repeatable, ultraclean, and gate-tunable NDR characteristics with a signature of intrinsic oscillation, and a large peak-to-valley current ratio (PVCR) of 3.6 at 300 K (4.6 at 7 K), making them suitable for practical applications. We show that the thermodynamic stability of the vdW tunnel diode circuit can be tuned from astability to bistability by altering the constraint through choosing a voltage or a current bias, respectively. In the astable mode under voltage bias, we demonstrate a compact, voltage-controlled oscillator without the need for an external tank circuit. In the bistable mode under current bias, we demonstrate a highly scalable, single-element, one-bit memory cell that is promising for dense random access memory applications in memory intensive computation architectures.
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Affiliation(s)
- Nithin Abraham
- Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Krishna Murali
- Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Kausik Majumdar
- Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore 560012, India
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Hwang Y, Kang SG, Shin N. Inherent Resistance of Seed-Mediated Grown MoSe 2 Monolayers to Defect Formation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:34297-34305. [PMID: 32618179 DOI: 10.1021/acsami.0c05558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recent progress in the chemical vapor deposition technique toward growing large-area and single-crystalline two-dimensional (2D) transition metal dichalcogenides (TMDs) has resulted in an electronic/optoelectronic device performance that rivals that of their top-down counterparts, despite the extensive use of hydrogen, a common reducing agent that readily generates defects in TMDs. Herein, we report that 2D MoSe2 domains containing oxide seeds are resistant to hydrogen-induced defect generation. Specifically, we observed that the etching of the edges of seed-containing MoSe2 was significantly less than that of pristine MoSe2, without apparent seed particles, under the same H2 annealing conditions. Our systematic approach for controlling the H2 exposure time indicates that the oxidation of Mo and the edge roughening of seedless MoSe2 coincidentally increase after H2 exposure owing to the formation of Se vacancy followed by Mo oxidation, which is not the case with seed-containing MoSe2. An ab initio calculation indicates that hydrogen preferentially adsorbs more onto O bonded to Mo than onto Se, providing further evidence of the resistance of seeded MoSe2 to hydrogen etching. This finding provides an insight into controlling defect formation in 2D TMDs by employing sacrificial adsorption sites for reactive species (i.e., hydrogen).
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Affiliation(s)
- Yunjeong Hwang
- Department of Chemistry and Chemical Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Sung Gu Kang
- School of Chemical Engineering, University of Ulsan, Ulsan 680-749, Republic of Korea
| | - Naechul Shin
- Department of Chemistry and Chemical Engineering, Inha University, Incheon 22212, Republic of Korea
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Lee J, Duong NT, Bang S, Park C, Nguyen DA, Jeon H, Jang J, Oh HM, Jeong MS. Modulation of Junction Modes in SnSe 2/MoTe 2 Broken-Gap van der Waals Heterostructure for Multifunctional Devices. NANO LETTERS 2020; 20:2370-2377. [PMID: 32031411 DOI: 10.1021/acs.nanolett.9b04926] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We study the electronic and optoelectronic properties of a broken-gap heterojunction composed of SnSe2 and MoTe2 with gate-controlled junction modes. Owing to the interband tunneling current, our device can act as an Esaki diode and a backward diode with a peak-to-valley current ratio approaching 5.7 at room temperature. Furthermore, under an 811 nm laser irradiation the heterostructure exhibits a photodetectivity of up to 7.5 × 1012 Jones. In addition, to harness the electrostatic gate bias, Voc can be tuned from negative to positive by switching from the accumulation mode to the depletion mode of the heterojunction. Additionally, a photovoltaic effect with a fill factor exceeding 41% was observed, which highlights the significant potential for optoelectronic applications. This study not only demonstrates high-performance multifunctional optoelectronics based on the SnSe2/MoTe2 heterostructure but also provides a comprehensive understanding of broken-band alignment and its applications.
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Affiliation(s)
- Juchan Lee
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Ngoc Thanh Duong
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Seungho Bang
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Chulho Park
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Duc Anh Nguyen
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hobeom Jeon
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jiseong Jang
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hye Min Oh
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Mun Seok Jeong
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
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8
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Fan S, Vu QA, Lee S, Phan TL, Han G, Kim YM, Yu WJ, Lee YH. Tunable Negative Differential Resistance in van der Waals Heterostructures at Room Temperature by Tailoring the Interface. ACS NANO 2019; 13:8193-8201. [PMID: 31260265 DOI: 10.1021/acsnano.9b03342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Vertically stacked two-dimensional van der Waals (vdW) heterostructures, used to obtain homogeneity and band steepness at interfaces, exhibit promising performance for band-to-band tunneling (BTBT) devices. Esaki tunnel diodes based on vdW heterostructures, however, yield poor current density and peak-to-valley ratio, inferior to those of three-dimensional materials. Here, we report the negative differential resistance (NDR) behavior in a WSe2/SnSe2 heterostructure system at room temperature and demonstrate that heterointerface control is one of the keys to achieving high device performance by constructing WSe2/SnSe2 heterostructures in inert gas environments. While devices fabricated in ambient conditions show poor device performance due to the observed oxidation layer at the interface, devices fabricated in inert gas exhibit extremely high peak current density up to 1460 mA/mm2, 3-4 orders of magnitude higher than reported vdW heterostructure-based tunnel diodes, with a peak-to-valley ratio of more than 4 at room temperature. Besides, Pd/WSe2 contact in our device possesses a much higher Schottky barrier than previously reported Cr/WSe2 contact in the WSe2/SnSe2 device, which suppresses the thermionic emission current to less than the BTBT current level, enabling the observation of NDR at room temperature. Diode behavior can be further modulated by controlling the electrostatic doping and the tunneling barrier as well.
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Affiliation(s)
- Sidi Fan
- Center for Integrated Nanostructure Physics, Institute for Basic Science , Sungkyunkwan University , Suwon 16419 , Korea
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
| | - Quoc An Vu
- Center for Integrated Nanostructure Physics, Institute for Basic Science , Sungkyunkwan University , Suwon 16419 , Korea
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
| | - Sanghyub Lee
- Center for Integrated Nanostructure Physics, Institute for Basic Science , Sungkyunkwan University , Suwon 16419 , Korea
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
| | - Thanh Luan Phan
- Department of Electronic and Electrical Engineering , Sungkyunkwan University , Suwon 16419 , Korea
| | - Gyeongtak Han
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
| | - Young-Min Kim
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
| | - Woo Jong Yu
- Department of Electronic and Electrical Engineering , Sungkyunkwan University , Suwon 16419 , Korea
| | - Young Hee Lee
- Center for Integrated Nanostructure Physics, Institute for Basic Science , Sungkyunkwan University , Suwon 16419 , Korea
- Department of Energy Science, Department of Physics , Sungkyunkwan University , Suwon 16419 , Korea
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Duong NT, Lee J, Bang S, Park C, Lim SC, Jeong MS. Modulating the Functions of MoS 2/MoTe 2 van der Waals Heterostructure via Thickness Variation. ACS NANO 2019; 13:4478-4485. [PMID: 30938981 DOI: 10.1021/acsnano.9b00014] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Various functional devices including p-n forward, backward, and Zener diodes are realized with a van der Waals heterostructure that are composed of molybdenum disulfide (MoS2) and molybdenum ditelluride (MoTe2) by changing the thickness of the MoTe2 layer and common gate bias. In addition, the available negative differential transconductance of the heterostructure is utilized to fabricate a many-valued logic device that exhibits three different logic states ( i.e., a ternary inverter). Furthermore, the multivalued logic device can be transformed into a binary inverter using laser irradiation. This work provides a comprehensive understanding of the device fabrication and electronic-device design utilizing thickness control.
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Affiliation(s)
- Ngoc Thanh Duong
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
| | - Juchan Lee
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
| | - Seungho Bang
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
- Center for Integrated Nanostructure Physics , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
| | - Chulho Park
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
| | - Seong Chu Lim
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
- Center for Integrated Nanostructure Physics , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
| | - Mun Seok Jeong
- Department of Energy Science , Sungkyunkwan University (SKKU) , Suwon 16419 , Republic of Korea
- Center for Integrated Nanostructure Physics , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
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Park C, Duong NT, Bang S, Nguyen DA, Oh HM, Jeong MS. Photovoltaic effect in a few-layer ReS 2/WSe 2 heterostructure. NANOSCALE 2018; 10:20306-20312. [PMID: 30375621 DOI: 10.1039/c8nr07219a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Two-dimensional transition-metal dichalcogenides (TMDCs) are notable materials owing to their flexibility, transparency, and appropriate bandgaps. Because of their unique advantages, TMDC p-n diodes have been studied for next-generation electronics and optoelectronics. However, their efficiency must be increased for commercialization. In this study, we demonstrated a heterostructure composed of few-layer ReS2 and WSe2. This few-layer ReS2/WSe2 heterostructure exhibits a p-n junction and an n-n junction in different gate-bias regimes. In the p-n junction regime, the heterostructure shows outstanding rectification behavior. Additionally, we identify three carrier-transfer mechanisms - direct tunneling, Fowler-Nordheim tunneling, and the space charge region - depending on the drain bias. Furthermore, the photovoltaic effect is observed in this few-layer ReS2/WSe2 heterostructure. As a result, a high fill factor (≈ 0.56), power conversion (≈ 1.5%), and external quantum efficiency (≈ 15.3%) were obtained. This study provides new guidelines for flexible optoelectronic devices.
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Affiliation(s)
- Chulho Park
- Department of Energy Science, Sungkyunkwan University (SKKU), Suwon 16419, Korea.
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