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Shin H, Hong L, Park W, Shin J, Park JB. Frequency dependence of nanorod self-alignment using microfluidic methods. Nanotechnology 2024. [PMID: 38636472 DOI: 10.1088/1361-6528/ad403d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Dielectrophoresis is a potential candidate for aligning nanorods on electrodes, in which the interplay between electric fields and microfluidics is critically associated with its yield. Despite much of previous work on dielectrophoresis, the impact of frequency modulation on dielectrophoresis-driven nanowire self-assembly is insufficiently understood. In this work, we systematically explore the frequency dependence of the self-alignment of silicon nanowires using a microfluidic channel. We vary the frequency from 1kHz to 1000kHz and analyze the resulting alignments in conjunction with numerical analysis. Our experiment reveals an optimal alignment yield at approximately 100kHz, followed by a decrease in alignment efficiency. The nanorod self-alignments are influenced by multiple consequences, including the trapping effect, induced electrical double layer, electrohydrodynamic flow, and particle detachment. This study provides insights into the impact of frequency modulation of electric fields on the alignment of silicon nanorods using dielectrophoresis, broadening its use in various future nanotechnology applications.
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Affiliation(s)
- Hosan Shin
- Korea University - Sejong Campus, 2511 Sejong-ro, Sejong City, 30019, Korea, Sejong, 30019, Korea (the Republic of)
| | - Lia Hong
- Sookmyung Women's University, 100 Cheongpa-ro 47-gil, Yongsan-gu, Korea, 04310, Yongsan-gu, Seoul, 04310, Korea (the Republic of)
| | - Woosung Park
- Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 04107, Korea, Mapo-gu, Seoul, 04107, Korea (the Republic of)
| | - Jeeyoung Shin
- Sookmyung Women's University, Cheongpa-ro 47-gil 100(Cheongpa-dong 2-ga), Yongsan-Ku, Seoul, 04310, Korea, Yongsan-gu, Seoul, 04310, Korea (the Republic of)
| | - Jae Byung Park
- Korea University - Sejong Campus, 2511 Sejong-ro, Sejong City, 30019, Korea, Sejong, 30019, Korea (the Republic of)
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2
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Foradori SM, Prussack B, Berson A, Arnold MS. Assembly and Alignment of High Packing Density Carbon Nanotube Arrays Using Lithographically Defined Microscopic Water Features. ACS Nano 2024; 18:8259-8269. [PMID: 38437517 DOI: 10.1021/acsnano.3c12243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
High packing density aligned arrays of semiconducting carbon nanotubes (CNTs) are required for many electronics applications. Past work has shown that the accumulation of CNTs at a water-solvent interface can drive array self-assembly. Previously, the confining interface was a large-area, macroscopic feature. Here, we report on the CNT assembly on microscopic water features. Water microdroplets are formed on 10-100 μm wide hydrophilic stripes patterned on a substrate. Exposure to CNTs dispersed in solvent accumulates CNTs at the microdroplet-solvent interface, driving their alignment and deposition at the microdroplet-solvent-substrate contact line. Compared with macroscopic methods in which the contact line uncontrollably moves across the substrate as it is pulled out of the liquids, the hydrophilic patterns and microdroplets allow pinning of the contact line. As CNTs deposit, the contact line self-translates, allowing for dense CNT packing. We realize monolayer CNT arrays aligned within ±3.9° at density of 250 μm-1 and field effect transistors with a high current density of 1.9 mA μm-1 and transconductance of 1.2 mS μm-1 at -0.6 V drain bias and 60 nm channel length.
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Affiliation(s)
- Sean M Foradori
- Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Avenue, Madison, Wisconsin 53706, United States
| | - Brett Prussack
- Department of Mechanical Engineering, University of Wisconsin-Madison, 1513 University Avenue, Madison, Wisconsin 53706, United States
| | - Arganthaël Berson
- Department of Mechanical Engineering, University of Wisconsin-Madison, 1513 University Avenue, Madison, Wisconsin 53706, United States
| | - Michael S Arnold
- Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Avenue, Madison, Wisconsin 53706, United States
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3
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Liu B, Demir B, Gultakti CA, Marrs J, Gong Y, Li R, Oren EE, Hihath J. Self-Aligning Nanojunctions for Integrated Single-Molecule Circuits. ACS Nano 2024; 18:4972-4980. [PMID: 38214957 DOI: 10.1021/acsnano.3c10844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Robust, high-yield integration of nanoscale components such as graphene nanoribbons, nanoparticles, or single-molecules with conventional electronic circuits has proven to be challenging. This difficulty arises because the contacts to these nanoscale devices must be precisely fabricated with angstrom-level resolution to make reliable connections, and at manufacturing scales this cannot be achieved with even the highest-resolution lithographic tools. Here we introduce an approach that circumvents this issue by precisely creating nanometer-scale gaps between metallic carbon electrodes by using a self-aligning, solution-phase process, which allows facile integration with conventional electronic systems with yields approaching 50%. The electrode separation is controlled by covalently binding metallic single-walled carbon nanotube (mCNT) electrodes to individual DNA duplexes to create mCNT-DNA-mCNT nanojunctions, where the gap is precisely matched to the DNA length. These junctions are then integrated with top-down lithographic techniques to create single-molecule circuits that have electronic properties dominated by the DNA in the junction, have reproducible conductance values with low dispersion, and are stable and robust enough to be utilized as active, high-specificity electronic biosensors for dynamic single-molecule detection of specific oligonucleotides, such as those related to the SARS-CoV-2 genome. This scalable approach for high-yield integration of nanometer-scale devices will enable opportunities for manufacturing of hybrid electronic systems for a wide range of applications.
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Affiliation(s)
- Bo Liu
- Biodesign Center for Bioelectronics and Biosensors at Arizona State University, Tempe, Arizona 85287, United States
| | - Busra Demir
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara 06560, Turkey
- Department of Materials Science and Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara 06560, Tureky
| | - Caglanaz Akin Gultakti
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara 06560, Turkey
- Department of Materials Science and Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara 06560, Tureky
| | - Jonathan Marrs
- Department of Electrical and Computer Engineering, University of California, Davis, Davis, California 95616, United States
| | - Yichen Gong
- Biodesign Center for Bioelectronics and Biosensors at Arizona State University, Tempe, Arizona 85287, United States
| | - Ruihao Li
- Biodesign Center for Bioelectronics and Biosensors at Arizona State University, Tempe, Arizona 85287, United States
| | - Ersin Emre Oren
- Bionanodesign Laboratory, Department of Biomedical Engineering, TOBB University of Economics and Technology, Ankara 06560, Turkey
- Department of Materials Science and Nanotechnology Engineering, TOBB University of Economics and Technology, Ankara 06560, Tureky
| | - Joshua Hihath
- Biodesign Center for Bioelectronics and Biosensors at Arizona State University, Tempe, Arizona 85287, United States
- Department of Electrical and Computer Engineering, University of California, Davis, Davis, California 95616, United States
- School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, Arizona 85287, United States
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4
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Shan Y, Qian L, Wang J, Wang K, Zhou P, Li W, Shen W. Driving Principle and Stability Analysis of Vertical Comb-Drive Actuator for Scanning Micromirrors. Micromachines (Basel) 2024; 15:226. [PMID: 38398956 PMCID: PMC10892111 DOI: 10.3390/mi15020226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/29/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024]
Abstract
We have developed a manufacturing process for micromirrors based on microelectromechanical systems (MEMS) technology. The process involves designing an electrostatic vertically comb-driven actuator and utilizing a self-alignment process to produce a height difference between the movable comb structure and the fixed comb structure of the micromirror. To improve the stability of the micromirror, we propose four instability models in micromirror operation with the quasi-static driving principle and structure of the micromirror considered, which can provide a basic guarantee for the performance of vertical comb actuators. This analysis pinpoints factors leading to instability, including the left and right gap of the movable comb, the torsion beams of the micromirror, and the comb-to-beams distance. Ultimately, the voltages at which device failure occurs can be determined. We successfully fabricated a one-dimensional micromirror featuring a 0.8 mm mirror diameter and a 30 μm device layer thickness. The height difference between the movable and fixed comb structures was 10 μm. The micromirror was able to achieve a static mechanical angle of 2.25° with 60 V@DC. Stable operation was observed at voltages below 60 V, in close agreement with the theoretical calculations and simulations. At the driving voltage of 80 V, we observed the longitudinal displacement movement of the comb fingers. Furthermore, at a voltage of 129 V, comb adhesion occurred, resulting in device failure. This failure voltage corresponds to the lateral torsional failure voltage.
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Affiliation(s)
- Yameng Shan
- School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China; (Y.S.)
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Lei Qian
- School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China; (Y.S.)
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Junduo Wang
- School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China; (Y.S.)
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Kewei Wang
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Peng Zhou
- School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China; (Y.S.)
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Wenchao Li
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Wenjiang Shen
- School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China; (Y.S.)
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
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5
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Mu R, Zhang T, Li S. A Rapid Self-Alignment Strategy for a Launch Vehicle on an Offshore Launching Platform. Sensors (Basel) 2022; 23:339. [PMID: 36616936 PMCID: PMC9823459 DOI: 10.3390/s23010339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/23/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
To reduce the impact of offshore launching platform motion and swaying on the self-alignment accuracy of a launch vehicle, a rapid self-alignment strategy, which involves an optimal combination of anti-swaying coarse alignment (ASCA), backtracking navigation, and reverse Kalman filtering is proposed. During the entire alignment process, the data provided by the strapdown inertial navigation system (SINS) are stored and then applied to forward and backtrack self-alignment. This work elaborates the basic principles of coarse alignment and then analyzes the influence of ASCA time on alignment accuracy. An error model was built for the reverse fine alignment system. The coarse alignment was carried out based on the above work, then the state of the alignment system was retraced using the reverse inertial navigation solution and reverse Kalman filtering with the proposed strategy. A cycle-index control function was designed to approximate strict backtracking navigation. Finally, the attitude error was compensated for after the completion of the first and the last forward navigation. To demonstrate the effectiveness of the proposed strategy, numerical simulations were carried out in a scenario of launch vehicle motion and swaying. The proposed strategy can maximize the utilization of SINS data and hence improve the alignment accuracy and further reduce the alignment time. The results show that the fully autonomous alignment technology of the SINS can replace the complex optical aiming system and realize the determination of the initial attitude of a launch vehicle before launch.
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Affiliation(s)
- Rongjun Mu
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Tengfei Zhang
- School of Astronautics, Harbin Institute of Technology, Harbin 150001, China
| | - Shoupeng Li
- Institute of Modern Optics, Nankai University, Tianjin 300350, China
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6
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Yu S, Huang TH, Di Lallo A, Zhang S, Wang T, Fu Q, Su H. Bio-inspired design of a self-aligning, lightweight, and highly-compliant cable-driven knee exoskeleton. Front Hum Neurosci 2022; 16:1018160. [PMID: 36419645 PMCID: PMC9677347 DOI: 10.3389/fnhum.2022.1018160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/19/2022] [Indexed: 04/07/2024] Open
Abstract
Powered knee exoskeletons have shown potential for mobility restoration and power augmentation. However, the benefits of exoskeletons are partially offset by some design challenges that still limit their positive effects on people. Among them, joint misalignment is a critical aspect mostly because the human knee joint movement is not a fixed-axis rotation. In addition, remarkable mass and stiffness are also limitations. Aiming to minimize joint misalignment, this paper proposes a bio-inspired knee exoskeleton with a joint design that mimics the human knee joint. Moreover, to accomplish a lightweight and high compliance design, a high stiffness cable-tension amplification mechanism is leveraged. Simulation results indicate our design can reduce 49.3 and 71.9% maximum total misalignment for walking and deep squatting activities, respectively. Experiments indicate that the exoskeleton has high compliance (0.4 and 0.1 Nm backdrive torque under unpowered and zero-torque modes, respectively), high control bandwidth (44 Hz), and high control accuracy (1.1 Nm root mean square tracking error, corresponding to 7.3% of the peak torque). This work demonstrates performance improvement compared with state-of-the-art exoskeletons.
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Affiliation(s)
- Shuangyue Yu
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
| | - Tzu-Hao Huang
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
| | - Antonio Di Lallo
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
| | - Sainan Zhang
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
- Department of Mechanical Engineering, City College of New York, New York, NY, United States
| | - Tian Wang
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
| | - Qiushi Fu
- Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL, United States
- NeuroMechanical Systems Laboratory, Biionix (Bionic Materials, Implants & Interfaces) Cluster, University of Central Florida, Orlando, FL, United States
| | - Hao Su
- Lab of Biomechatronics and Intelligent Robotics, Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, United States
- Joint North Carolina State University/The University of North Carolina Department of Biomedical Engineering, NC State University, Raleigh, NC, United States
- Joint North Carolina State University/The University of North Carolina Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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7
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Abstract
The seamless coalescence of parallelly aligned 2D materials is the primary route toward the synthesis of wafer-scale single crystals (WSSCs) of 2D materials. The epitaxial growth of various 2D materials on a single-crystal substrate, which is an essential condition of the seamless coalescence approach, has been extensively explored in previous studies. Here, by using hexagonal boron nitride (hBN) growth on a liquid gold surface as an example, we demonstrate that growth of WSSCs of 2D materials via the seamless coalescence of self-aligned 2D islands on a liquid substrate is possible. Here we show that, in the presence of hydrogen, all the hBN edges tend to be hydrogen terminated and the coalescence of hBN islands occurs only if their crystallographic lattices of neighboring hBN islands are aligned parallelly. The mechanism of hBN self-alignment revealed in this study implies that, under the optimum experimental condition, the seamless coalescence of 2D materials on a liquid substrate is possible and thus provides guidance for synthesizing WSSCs of various 2D materials by using liquid phase substrates.
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Affiliation(s)
- Li-Ping Ding
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Department of Optoelectronic Science & Technology, School of Electronic Information and Artificial Intelligence, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Peng Shao
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Department of Optoelectronic Science & Technology, School of Electronic Information and Artificial Intelligence, Shaanxi University of Science & Technology, Xi'an 710021, China
| | - Feng Ding
- Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan 44919, Republic of Korea
- Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
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8
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He X, Jiang H, Li J, Ma Y, Fu B, Hu C. Dipole-Moment Induced Phototaxis and Fuel-Free Propulsion of ZnO/Pt Janus Micromotors. Small 2021; 17:e2101388. [PMID: 34173337 DOI: 10.1002/smll.202101388] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/15/2021] [Indexed: 06/13/2023]
Abstract
Light-driven micromotors have stimulated considerate interests due to their potentials in biomedicine, environmental remediation, or serving as the model system for non-equilibrium physics of active matter. Simultaneous control over the motion direction and speed of micro/nanomotors is crucial for their functionality but still difficult since Brownian motion always randomizes the orientations. Here, a highly efficient light-driven ZnO/Pt Janus micromotor capable of aligning itself to illumination direction and exhibiting negative phototaxis at high speeds (up to 32 µm s-1 ) without the addition of any chemical fuels is developed. A light-triggered self-built electric field parallel to the light illumination exists due to asymmetrical surface chemical reactions induced by the limited penetration depth of light along the illumination. The phototactic motion of the motor is achieved through electrophoretic rotation induced by the asymmetrical distribution of zeta potential on the two hemispheres of the Janus micromotor, into alignment with the electric field. Notably, similar phototactic propulsion is also achieved on TiO2 /Pt and CdS/Pt micromotors, which presents explicit proof of extending the mechanism of dipole-moment induced phototactic propulsion in other light-driven Janus micromotors. Finally, active transportation of yeast cells are achieved by the motor, proving its capability in performing complex tasks.
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Affiliation(s)
- Xiaoli He
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Huaide Jiang
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Jianjie Li
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Yanmei Ma
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Bi Fu
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Chengzhi Hu
- Shenzhen Key Laboratory of Biomimetic Robotics and Intelligent Systems, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
- Guangdong Provincial Key Laboratory of Human-Augmentation and Rehabilitation Robotics in Universities, Southern University of Science and Technology, Shenzhen, 518055, China
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9
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Gaviria Rojas WA, Beck ME, Sangwan VK, Guo S, Hersam MC. Ohmic-Contact-Gated Carbon Nanotube Transistors for High-Performance Analog Amplifiers. Adv Mater 2021; 33:e2100994. [PMID: 34270835 DOI: 10.1002/adma.202100994] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 04/14/2021] [Indexed: 06/13/2023]
Abstract
The growing demand for ubiquitous data collection has driven the development of sensing technologies with local data processing. As a result, solution-processed semiconductors are widely employed due to their compatibility with low-cost additive manufacturing on a wide range of substrates. However, to fully realize their potential in sensing applications, high-performance scalable analog amplifiers must be realized. Here, ohmic-contact-gated transistors (OCGTs) based on solution-processed semiconducting single-walled carbon nanotubes are introduced to address this unmet need. This new device concept enables output current saturation in the short-channel limit without compromising output current drive. The resulting OCGTs are used in common-source amplifiers to achieve the highest width-normalized output current (≈30 µA µm-1 ) and length-scaled signal gain (≈230 µm-1 ) to date for solution-processed semiconductors. The utility of these amplifiers for emerging sensing technologies is demonstrated by the amplification of complex millivolt-scale analog biological signals including the outputs of electromyography, photoplethysmogram, and accelerometer sensors. Since the OCGT design is compatible with other solution-processed semiconducting materials, this work establishes a general route to high-performance, solution-processed analog electronics.
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Affiliation(s)
- William A Gaviria Rojas
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Megan E Beck
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Vinod K Sangwan
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Silu Guo
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
| | - Mark C Hersam
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208, USA
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL, 60208, USA
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10
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Cai L, He W, Xue X, Huang J, Zhou K, Zhou X, Xu Z, Yu G. In situ growth of large-area and self-aligned graphene nanoribbon arrays on liquid metal. Natl Sci Rev 2020; 8:nwaa298. [PMID: 34987835 PMCID: PMC8692927 DOI: 10.1093/nsr/nwaa298] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 11/21/2020] [Accepted: 12/08/2020] [Indexed: 11/14/2022] Open
Abstract
Intrinsic graphene features semi-metallic characteristics that limit its applications in electronic devices, whereas graphene nanoribbons (GNRs) are promising semiconductors because of their bandgap-opening feature. However, the controllable mass-fabrication of high-quality GNR arrays remains a major challenge. In particular, the in situ growth of GNR arrays through template-free chemical vapor deposition (CVD) has not been realized. Herein, we report a template-free CVD strategy to grow large-area, high-quality and self-aligned GNR arrays on liquid copper surface. The width of as-grown GNR could be optimized to sub-10 nm with aspect ratio up to 387, which is higher than those of reported CVD-GNRs. The study of the growth mechanism indicates that a unique comb-like etching-regulated growth process caused by a trace hydrogen flow guides the formation of the mass-produced self-aligned GNR arrays. Our approach is operationally simple and efficient, offering an assurance for the use of GNR arrays in integrated circuits.
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Affiliation(s)
- Le Cai
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Wanzhen He
- Applied Mechanics Laboratory, Department of Engineering Mechanics and Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
| | - Xudong Xue
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jianyao Huang
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Ke Zhou
- Applied Mechanics Laboratory, Department of Engineering Mechanics and Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
| | - Xiahong Zhou
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhiping Xu
- Applied Mechanics Laboratory, Department of Engineering Mechanics and Centre for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
| | - Gui Yu
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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11
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Chang B, Jin J, Zhou Q. Surface Tension-Based Alignment of Microfibers on Hydrophilic-Superhydrophobic Grooved Surfaces. Micromachines (Basel) 2020; 11:mi11110973. [PMID: 33138311 PMCID: PMC7716217 DOI: 10.3390/mi11110973] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 10/24/2020] [Accepted: 10/29/2020] [Indexed: 11/21/2022]
Abstract
Alignment and orderly distribution of microfibers have a major effect on the mechanical, electrical, and thermal properties of the fiber reinforced materials, biomimetic materials, and soft microsensors. However, it is still a challenging task to precisely align and distribute microfibers and construct complex patterns. This paper proposes a surface tension-based method to align and orderly distribute microfibers. A model was developed to simulate the surface tension driven alignment of the microfiber. We designed and fabricated hydrophilic–superhydrophobic grooved surfaces. We demonstrated that the microfibers can self-align to the hydrophilic–superhydrophobic grooves with different geometries. We studied the influence of the volume of the droplet and bias on the alignment success rate. The results indicate that the process can tolerate large variations of the bias and the volume, unless the volume is not enough to cover the groove. We further investigated the influence of the width of the groove on the alignment accuracy. The results show that the alignment accuracy is largely depending on the size difference between the groove and the microfiber; the better the size of the groove matches the size of the fiber, the higher the alignment accuracy will be achieved. The proposed method has great potential in construction of complex microstructures using microfibers.
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Affiliation(s)
- Bo Chang
- College of Mechanical and Electrical Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China;
- Correspondence:
| | - Jialong Jin
- College of Mechanical and Electrical Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China;
| | - Quan Zhou
- School of Electrical Engineering, Aalto University, FI-00076 Aalto, Finland;
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12
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Abstract
Many complex natural and artificial systems are composed of large numbers of elementary building blocks, such as organisms made of many biological cells or processors made of many electronic transistors. This modular substrate is essential to the evolution of biological and technological complexity, but has been difficult to replicate for mechanical systems. This study seeks to answer if layered assembly can engender exponential gains in the speed and efficacy of block or cell-based manufacturing processes. A key challenge is how to deterministically assemble large numbers of small building blocks in a scalable manner. Here, we describe two new layered assembly principles that allow assembly faster than linear time, integrating n modules in O(n2/3) and O(n1/3) time: one process uses a novel opto-capillary effect to selectively deposit entire layers of building blocks at a time, and a second process jets building block rows in rapid succession. We demonstrate the fabrication of multi-component structures out of up to 20 000 millimetre scale spherical building blocks in 3 h. While these building blocks and structures are still simple, we suggest that scalable layered assembly approaches, combined with a growing repertoire of standardized passive and active building blocks could help bridge the meso-scale assembly gap, and open the door to the fabrication of increasingly complex, adaptive and recyclable systems.
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Affiliation(s)
- Jonathan Hiller
- School of Mechanical and Aerospace Engineering, Ithaca, NY 14853, USA
| | - Joni Mici
- Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA
| | - Hod Lipson
- School of Mechanical and Aerospace Engineering, Ithaca, NY 14853, USA.,Computing and Information Science, Cornell University, Ithaca, NY 14853, USA
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13
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Lee I, Oh J, Yu H, Kim C, Lee SJ. Method for Improved Performance of Fixed-Gain Self-Alignment in the Temperature Stabilizing State. Sensors (Basel) 2020; 20:s20082188. [PMID: 32294931 PMCID: PMC7218872 DOI: 10.3390/s20082188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 06/11/2023]
Abstract
Self-alignment (or initial alignment) is the process by which the Inertial Navigation System (INS) is aligned using only measurements from the inertial sensors and the reference navigation information in the stationary state. The main purpose of self-alignment is to calculate the initial attitude of the INS. The accuracy of self-alignment is determined by the performance grade of the inertial sensors, for instance, the accuracy of the horizontal attitude by the horizontal accelerometer and the accuracy of the vertical attitude by the East-axis gyro. Therefore, uncertain errors in the inertial sensors degrade the performance of self-alignment. The focus of this paper is the temperature stabilizing error of accelerometers, a form of uncertain error. An analysis is presented of how the temperature stabilizing error affect the accuracy of self-alignment. From the analysis, a method is proposed to improve performance by curve fitting the horizontal control rates. This is then verified experimentally.
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Affiliation(s)
- Inseop Lee
- Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Korea; (J.O.); (H.Y.); (C.K.)
| | - Juhyun Oh
- Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Korea; (J.O.); (H.Y.); (C.K.)
| | - Haesung Yu
- Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Korea; (J.O.); (H.Y.); (C.K.)
| | - Cheonjoong Kim
- Agency for Defense Development, Yuseong P.O. Box 35, Daejeon 34186, Korea; (J.O.); (H.Y.); (C.K.)
| | - Sang Jeong Lee
- Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea;
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14
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Hong S, Kim SY, Son DH, Kim SH, Kim YI, Yang KJ, Heo YW, Kang JK, Kim DH. Self-Alignment of Bottom CZTSSe by Patterning of an Al 2O 3 Intermediate Layer. Nanomaterials (Basel) 2019; 10:E43. [PMID: 31878052 DOI: 10.3390/nano10010043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 11/26/2022]
Abstract
When CZTSSe is synthesized using a metal precursor, large voids of nonuniform size form at Mo back contact side. Herein, we demonstrate that the voids and CZTSSe in the lower part of the CZTSSe double layer can be controlled by using an Al2O3-patterned Mo substrate. The CZTSSe in the lower part self-aligns on the Mo-exposed area, while the voids self-align on the Al2O3-coated area. The origin of the self-alignment is expected to be the difference in bonding characteristics between liquid Sn and the metal or oxide surface, e.g., Al2O3. Good wettability generally forms between nonreactive liquid metals and metal surfaces due to the strong metallic bonding. By contrast, poor wettability generally forms between nonreactive liquid metals and oxide surfaces due to the weak van der Waals bonding between the liquid metal and the oxide layer. When the patterning was added, the device efficiency tended to decrease from 8.6% to 10.5%.
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15
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Moon DH, Kim D, Hong YD. Intention Detection Using Physical Sensors and Electromyogram for a Single Leg Knee Exoskeleton. Sensors (Basel) 2019; 19:E4447. [PMID: 31615048 DOI: 10.3390/s19204447] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 09/27/2019] [Accepted: 10/10/2019] [Indexed: 12/03/2022]
Abstract
In this paper, we present a knee exoskeleton. Due to the complicated structure of the knee, an exoskeleton can limit the wearer’s movement (e.g., when completely sitting down). To prevent this, the proposed exoskeleton is designed to move the ankle part prismatically, so the movement of the wearer is not limited. In addition, the developed exoskeleton could be worn on only one leg, but in this case, it is difficult to detect the intention because the relative relationship information of the two legs is unknown. For this purpose, the length between the knee center of rotation and the ankle (LBKA) was measured and used for intention detection. Using a physical sensor—an encoder and an LBKA sensor, the success rate of intention detection was 82.1%. By additionally using an electromyogram (EMG) sensor, the success rate of intention detection was increased to 92%, and the intention detection was also 27.1 ms faster on average.
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16
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Jang M, Kim JS, Kim JH, Bae DH, Kim MJ, Son D, Kim YT, Um SH, Kim YH, Kim J. Surface-Controlled Molecular Self-Alignment in Polymer Actuators for Flexible Microrobot Applications. Polymers (Basel) 2019; 11:polym11040736. [PMID: 31018560 PMCID: PMC6523470 DOI: 10.3390/polym11040736] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/14/2019] [Accepted: 04/18/2019] [Indexed: 11/16/2022] Open
Abstract
Polymer actuators are important components in lab-on-a-chip and micromechanical systems because of the inherent properties that result from their large and fast mechanical responses induced by molecular-level deformations (e.g., isomerization). They typically exhibit bending movements via asymmetric contraction or expansion with respect to changes in environmental conditions. To enhance the mechanical properties of actuators, a strain gradient should be introduced by regulating the molecular alignment; however, the miniaturization of polymer actuators for microscale systems has raised concerns regarding the complexity of such molecular control. Herein, a novel method for the fabrication of micro-actuators using a simple molecular self-alignment method is presented. Amphiphilic molecules that consist of azobenzene mesogens were located between the hydrophilic and hydrophobic surfaces, which resulted in a splayed alignment. Thereafter, molecular isomerization on the surface induced a large strain gradient and bending movement of the actuator under ultraviolet-light irradiation. Moreover, the microelectromechanical systems allowed for the variation of the actuator size below the micron scale. The mechanical properties of the fabricated actuators such as the bending direction, maximum angle, and response time were evaluated with respect to their thicknesses and lengths. The derivatives of the polymer actuator microstructure may contribute to the development of novel applications in the micro-robotics field.
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Affiliation(s)
- Minsu Jang
- Center for Bionics, Korea Institute of Science and Technology, Seoul 02792, Korea.
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Korea.
| | - Jun Sik Kim
- Center for Bionics, Korea Institute of Science and Technology, Seoul 02792, Korea.
- School of Electrical Engineering, Korea University, Seoul 02841, Korea.
| | - Ji-Hun Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea.
| | - Do Hyun Bae
- Department of Biomedical Engineering, Sungkyunkwan University, Suwon 16419, Korea.
| | - Min Jun Kim
- Department of Mechanical Engineering, Southern Methodist University, Dallas, TX 75275, USA.
| | - Donghee Son
- Center for Bionics, Korea Institute of Science and Technology, Seoul 02792, Korea.
| | - Yong-Tae Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea.
| | - Soong Ho Um
- School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Korea.
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea.
| | - Yong Ho Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea.
- Department of Biomedical Engineering, Sungkyunkwan University, Suwon 16419, Korea.
| | - Jinseok Kim
- Center for Bionics, Korea Institute of Science and Technology, Seoul 02792, Korea.
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17
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Tian Z, Li S, Kiravittaya S, Xu B, Tang S, Zhen H, Lu W, Mei Y. Selected and Enhanced Single Whispering-Gallery Mode Emission from a Mesostructured Nanomembrane Microcavity. Nano Lett 2018; 18:8035-8040. [PMID: 30427684 DOI: 10.1021/acs.nanolett.8b04259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Quantum sciences are revolutionizing computing and communication technologies, in which single-photon emitters are the key components for creating strong quantum entanglement. Color centers in diamonds in coupled-cavity systems are considered great candidates for the efficient generation of quantum carriers over other solid-state emitters. Owing to the multi-mode nature of high quality factor ( Q) diamond cavities, however, it is a grand challenge to the achievement of single photon emission with high rate and indistinguishability. To this end, a single-mode high- Q diamond cavity is highly desired. Here, we report a diamond mesostructured nanomembrane microcavity of a discrete rotational symmetry that selectively produces the desired single-mode emission in a broad spectrum. The strategic rolling up of a flexible diamond nanomembrane with aligned holes effectively defines the designed symmetry while maintaining the high- Q resonance through the whispering-gallery mode supported in the central hollow microcavity. The demonstrated diamond mesostructured microcavity features a distinct and enhanced single-mode emission, a step toward efficient quantum sources with designed positions or bands for quantum information technology.
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Affiliation(s)
- Ziao Tian
- Department of Materials Science, State Key Laboratory of ASIC and Systems , Fudan University , 220 Handan Road , Shanghai 200433 , China
- State Key Laboratory of Functional Materials for Informatics , Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences , Shanghai 200050 , China
| | - Shilong Li
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , 500 Yutian Road , Shanghai 200083 , China
| | - Suwit Kiravittaya
- Department of Electrical and Computer Engineering, Faculty of Engineering , Naresuan University , Taphoo, Muang, Phitsanulok 65000 , Thailand
| | - Borui Xu
- Department of Materials Science, State Key Laboratory of ASIC and Systems , Fudan University , 220 Handan Road , Shanghai 200433 , China
| | - Shiwei Tang
- Department of Materials Science, State Key Laboratory of ASIC and Systems , Fudan University , 220 Handan Road , Shanghai 200433 , China
| | - Honglou Zhen
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , 500 Yutian Road , Shanghai 200083 , China
| | - Wei Lu
- State Key Laboratory of Infrared Physics , Shanghai Institute of Technical Physics, Chinese Academy of Sciences , 500 Yutian Road , Shanghai 200083 , China
| | - YongFeng Mei
- Department of Materials Science, State Key Laboratory of ASIC and Systems , Fudan University , 220 Handan Road , Shanghai 200433 , China
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18
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Kaltwasser M, Schmidt U, Biswas S, Reiprich J, Schlag L, Isaac NA, Stauden T, Jacobs HO. Core-Shell Transformation-Imprinted Solder Bumps Enabling Low-Temperature Fluidic Self-Assembly and Self-Alignment of Chips and High Melting Point Interconnects. ACS Appl Mater Interfaces 2018; 10:40608-40613. [PMID: 30433752 DOI: 10.1021/acsami.8b12390] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We demonstrate the realization of core-shell transformation-imprinted solder bumps to enable low-temperature chip assembly, while providing a route to high-temperature interconnects through transformation. The reported core-shell solder bump uses a lower melting point BiIn-based shell and a higher melting point Sn core in the initial stage. The bumps enable fluidic self-assembly and self-alignment at relatively low temperatures (60-80 °C). The bumps use the high surface free energy of the liquid shell during the self-assembly to capture freely suspended Si dies inside a heated (80 °C) water bath, leading to well-ordered defect-free chip arrays; the molten liquid shell wets the metal contact (binding site) on the chips and yields self-aligned and electrically connected devices. The solid core provides the anchor point to the substrate. After the completion of the assembly, a short reflow raises the melting point, yielding a solid electrical connection. The low melting point liquid diffuses into the high melting point core. The tuning of the material ratios leads to tailored transformation-imprinted solders with high melting points (160-206 °C) in the final structure.
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Affiliation(s)
- Mahsa Kaltwasser
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Udo Schmidt
- Fachgebiet Elektrochemie und Galvanotechnik , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 6 , Ilmenau D-98693 , Germany
| | - Shantonu Biswas
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Johannes Reiprich
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Leslie Schlag
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Nishchay Angel Isaac
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Thomas Stauden
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
| | - Heiko O Jacobs
- Fachgebiet Nanotechnologie , Technische Universität Ilmenau , Gustav-Kirchhoff-Strasse 1 , Ilmenau D-98693 , Germany
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19
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Luo X, Zhong J, Zhou Q, Du S, Yuan S, Liu Y. Cationic Reduced Graphene Oxide as Self-Aligned Nanofiller in the Epoxy Nanocomposite Coating with Excellent Anticorrosive Performance and Its High Antibacterial Activity. ACS Appl Mater Interfaces 2018; 10:18400-18415. [PMID: 29727162 DOI: 10.1021/acsami.8b01982] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The design and preparation of an excellent corrosion protection coating is still a grand challenge and is essential for large-scale practical application. Herein, a novel cationic reduced graphene oxide (denoted as RGO-ID+)-based epoxy coating was fabricated for corrosion protection. RGO-ID+ was synthesized by in situ synthesis and salification reaction, which is stable dispersion in water and epoxy latex, and the self-aligned RGO-ID+-reinforced cathodic electrophoretic epoxy nanocomposite coating (denoted as RGO-ID+ coating) at the surface of metal was prepared by electrodeposition. The self-alignment of RGO-ID+ in the coatings is mainly attributed to the electric field force. The significantly enhanced anticorrosion performance of RGO-ID+ coating is proved by a series of electrochemical measurements in different concentrated NaCl solutions and salt spray tests. This superior anticorrosion property benefits from the self-aligned RGO-ID+ nanosheets and the quaternary-N groups present in the RGO-ID+ nanocomposite coating. Interestingly, the RGO-ID+ also exhibits a high antibacterial activity toward Escherichia coli with 83.4 ± 1.3% antibacterial efficiency, which is attributed to the synergetic effects of RGO-ID+ and the electrostatic attraction and hydrogen bonding between RGO-ID+ and E. coli. This work offers new opportunities for the successful development of effective corrosion protection and self-antibacterial coatings.
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Affiliation(s)
- Xiaohu Luo
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
- School of Chemistry and Chemical Engineering , Qiannan Normal University for Nationalities , Duyun , Guizhou 558000 , People's Republic of China
| | - Jiawen Zhong
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
| | - Qiulan Zhou
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
| | - Shuo Du
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
| | - Song Yuan
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
| | - Yali Liu
- State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha , Hunan 410082 , People's Republic of China
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20
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Xu X, Xu X, Zhang T, Li Y, Tong J. A Kalman Filter for SINS Self-Alignment Based on Vector Observation. Sensors (Basel) 2017; 17:E264. [PMID: 28146059 DOI: 10.3390/s17020264] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 11/17/2022]
Abstract
In this paper, a self-alignment method for strapdown inertial navigation systems based on the q-method is studied. In addition, an improved method based on integrating gravitational apparent motion to form apparent velocity is designed, which can reduce the random noises of the observation vectors. For further analysis, a novel self-alignment method using a Kalman filter based on adaptive filter technology is proposed, which transforms the self-alignment procedure into an attitude estimation using the observation vectors. In the proposed method, a linear psuedo-measurement equation is adopted by employing the transfer method between the quaternion and the observation vectors. Analysis and simulation indicate that the accuracy of the self-alignment is improved. Meanwhile, to improve the convergence rate of the proposed method, a new method based on parameter recognition and a reconstruction algorithm for apparent gravitation is devised, which can reduce the influence of the random noises of the observation vectors. Simulations and turntable tests are carried out, and the results indicate that the proposed method can acquire sound alignment results with lower standard variances, and can obtain higher alignment accuracy and a faster convergence rate.
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21
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Xu M, Xue Z, Wang J, Zhao Y, Duan Y, Zhu G, Yu L, Xu J, Wang J, Shi Y, Chen K, Roca I Cabarrocas P. Heteroepitaxial Writing of Silicon-on-Sapphire Nanowires. Nano Lett 2016; 16:7317-7324. [PMID: 27960468 DOI: 10.1021/acs.nanolett.6b02004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The heteroepitaxial growth of crystal silicon thin films on sapphire, usually referred to as SoS, has been a key technology for high-speed mixed-signal integrated circuits and processors. Here, we report a novel nanoscale SoS heteroepitaxial growth that resembles the in-plane writing of self-aligned silicon nanowires (SiNWs) on R-plane sapphire. During a low-temperature growth at <350 °C, compared to that required for conventional SoS fabrication at >900 °C, the bottom heterointerface cultivates crystalline Si pyramid seeds within the catalyst droplet, while the vertical SiNW/catalyst interface subsequently threads the seeds into continuous nanowires, producing self-oriented in-plane SiNWs that follow a set of crystallographic directions of the sapphire substrate. Despite the low-temperature fabrication process, the field effect transistors built on the SoS-SiNWs demonstrate a high on/off ratio of >5 × 104 and a peak hole mobility of >50 cm2/V·s. These results indicate the novel potential of deploying in-plane SoS nanowire channels in places that require high-performance nanoelectronics and optoelectronics with a drastically reduced thermal budget and a simplified manufacturing procedure.
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Affiliation(s)
- Mingkun Xu
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
- College of Mechanical and Electronic Engineering, Chaohu University , 238000, Chaohu, China
| | - Zhaoguo Xue
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Jimmy Wang
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Yaolong Zhao
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Yao Duan
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Guangyao Zhu
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Linwei Yu
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
- LPICM, CNRS/Ecole Polytechnique, Université Paris-Saclay , 91128 Palaiseau, France
| | - Jun Xu
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Junzhuan Wang
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Yi Shi
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
| | - Kunji Chen
- National Laboratory of Solid State Microstructures/School of Electronics Science and Engineering/Collaborative Innovation Center of Advanced Microstructures, Nanjing University , 210093 Nanjing, People's Republic of China
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22
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Liu Y, Guo J, Wu Y, Zhu E, Weiss NO, He Q, Wu H, Cheng HC, Xu Y, Shakir I, Huang Y, Duan X. Pushing the Performance Limit of Sub-100 nm Molybdenum Disulfide Transistors. Nano Lett 2016; 16:6337-6342. [PMID: 27579678 DOI: 10.1021/acs.nanolett.6b02713] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Two-dimensional semiconductors (2DSCs) such as molybdenum disulfide (MoS2) have attracted intense interest as an alternative electronic material in the postsilicon era. However, the ON-current density achieved in 2DSC transistors to date is considerably lower than that of silicon devices, and it remains an open question whether 2DSC transistors can offer competitive performance. A high current device requires simultaneous minimization of the contact resistance and channel length, which is a nontrivial challenge for atomically thin 2DSCs, since the typical low contact resistance approaches for 2DSCs either degrade the electronic properties of the channel or are incompatible with the fabrication process for short channel devices. Here, we report a new approach toward high-performance MoS2 transistors by using a physically assembled nanowire as a lift-off mask to create ultrashort channel devices with pristine MoS2 channel and self-aligned low resistance metal/graphene hybrid contact. With the optimized contact in short channel devices, we demonstrate sub-100 nm MoS2 transistor delivering a record high ON-current of 0.83 mA/μm at 300 K and 1.48 mA/μm at 20 K, which compares well with that of silicon devices. Our study, for the first time, demonstrates that the 2DSC transistors can offer comparable performance to the 2017 target for silicon transistors in International Technology Roadmap for Semiconductors (ITRS), marking an important milestone in 2DSC electronics.
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Affiliation(s)
- Yuan Liu
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Jian Guo
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Yecun Wu
- Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States
| | - Enbo Zhu
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Nathan O Weiss
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Qiyuan He
- Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States
| | - Hao Wu
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Hung-Chieh Cheng
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
| | - Yang Xu
- Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States
| | - Imran Shakir
- Sustainable Energy Technologies Centre, College of Engineering, King Saud University , Riyadh 11421, Kingdom of Saudi Arabia
| | - Yu Huang
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
- California Nanosystems Institute, University of California , Los Angeles, California 90095, United States
| | - Xiangfeng Duan
- Department of Materials Science and Engineering, University of California , Los Angeles, California 90095, United States
- California Nanosystems Institute, University of California , Los Angeles, California 90095, United States
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23
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Luo G, Teh KS, Liu Y, Zang X, Wen Z, Lin L. Direct-Write, Self-Aligned Electrospinning on Paper for Controllable Fabrication of Three-Dimensional Structures. ACS Appl Mater Interfaces 2015; 7:27765-70. [PMID: 26592741 DOI: 10.1021/acsami.5b08909] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Electrospinning, a process that converts a solution or melt droplet into an ejected jet under a high electric field, is a well-established technique to produce one-dimensional (1D) fibers or two-dimensional (2D) randomly arranged fibrous meshes. Nevertheless, the direct electrospinning of fibers into controllable three-dimensional (3D) architectures is still a nascent technology. Here, we apply near-field electrospinning (NFES) to directly write arbitrarily shaped 3D structures through consistent and spatially controlled fiber-by-fiber stacking of polyvinylidene fluoride (PVDF) fibers. An element central to the success of this 3D electrospinning is the use of a printing paper placed on the grounded conductive plate and acting as a fiber collector. Once deposited on the paper, residual solvents from near-field electrospun fibers can infiltrate the paper substrate, enhancing the charge transfer between the deposited fibers and the ground plate via the fibrous network within the paper. Such charge transfer grounds the deposited fibers and turns them into locally fabricated electrical poles, which attract subsequent in-flight fibers to deposit in a self-aligned manner on top of each other. This process enables the design and controlled fabrication of electrospun 3D structures such as grids, walls, hollow cylinders, and other 3D logos. As such, this technique has the potential to advance the existing electrospinning technologies in constructing 3D structures for biomedical, microelectronics, and MEMS/NMES applications.
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Affiliation(s)
- Guoxi Luo
- College of Optoelectronic Engineering, Chongqing University , Chongqing 400044, China
- Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States
| | - Kwok Siong Teh
- Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States
- School of Engineering, San Francisco State University , San Francisco, California 94132, United States
| | - Yumeng Liu
- Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States
| | - Xining Zang
- Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States
| | - Zhiyu Wen
- College of Optoelectronic Engineering, Chongqing University , Chongqing 400044, China
| | - Liwei Lin
- Department of Mechanical Engineering, University of California , Berkeley, California 94720, United States
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24
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Tan C, Zhu X, Su Y, Wang Y, Wu Z, Gu D. A New Analytic Alignment Method for a SINS. Sensors (Basel) 2015; 15:27930-53. [PMID: 26556353 PMCID: PMC4701262 DOI: 10.3390/s151127930] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Revised: 10/03/2015] [Accepted: 10/28/2015] [Indexed: 11/16/2022]
Abstract
Analytic alignment is a type of self-alignment for a Strapdown inertial navigation system (SINS) that is based solely on two non-collinear vectors, which are the gravity and rotational velocity vectors of the Earth at a stationary base on the ground. The attitude of the SINS with respect to the Earth can be obtained directly using the TRIAD algorithm given two vector measurements. For a traditional analytic coarse alignment, all six outputs from the inertial measurement unit (IMU) are used to compute the attitude. In this study, a novel analytic alignment method called selective alignment is presented. This method uses only three outputs of the IMU and a few properties from the remaining outputs such as the sign and the approximate value to calculate the attitude. Simulations and experimental results demonstrate the validity of this method, and the precision of yaw is improved using the selective alignment method compared to the traditional analytic coarse alignment method in the vehicle experiment. The selective alignment principle provides an accurate relationship between the outputs and the attitude of the SINS relative to the Earth for a stationary base, and it is an extension of the TRIAD algorithm. The selective alignment approach has potential uses in applications such as self-alignment, fault detection, and self-calibration.
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Affiliation(s)
- Caiming Tan
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Xinhua Zhu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Yan Su
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Yu Wang
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Zhiqiang Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Dongbing Gu
- School of Computer Science and Electronic Engineering, University of Essex, Essex CO4 3SQ, UK.
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25
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Liang J, Zhang L, Wang L, Dong Y, Ueda T. Flip Chip Bonding of a Quartz MEMS-Based Vibrating Beam Accelerometer. Sensors (Basel) 2015; 15:22049-59. [PMID: 26340632 PMCID: PMC4610569 DOI: 10.3390/s150922049] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/23/2015] [Accepted: 08/26/2015] [Indexed: 11/19/2022]
Abstract
In this study, a novel method to assemble a micro-accelerometer by a flip chip bonding technique is proposed and demonstrated. Both the main two parts of the accelerometer, a double-ended tuning fork and a base-proof mass structure, are fabricated using a quartz wet etching process on Z cut quartz wafers with a thickness of 100 μm and 300 μm, respectively. The finite element method is used to simulate the vibration mode and optimize the sensing element structure. Taking advantage of self-alignment function of the flip chip bonding process, the two parts were precisely bonded at the desired joint position via AuSn solder. Experimental demonstrations were performed on a maximum scale of 4 × 8 mm2 chip, and high sensitivity up to 9.55 Hz/g with a DETF resonator and a Q value of 5000 in air was achieved.
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Affiliation(s)
- Jinxing Liang
- Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology, Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China.
| | - Liyuan Zhang
- Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology, Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China.
| | - Ling Wang
- School of Automation, Southeast University, Nanjing 210096, China.
| | - Yuan Dong
- Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology, Ministry of Education, School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China.
| | - Toshitsugu Ueda
- Graduate School of Information, Production and Systems, Waseda University, Kitakyushu 808-0135, Japan.
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26
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Abstract
A comparative study of the electronic structure of methylammonium (CH3NH3) in organometallic lead triiodide perovskite (CH3NH3PbI3) thin films synthesized using either one- or two-step deposition protocols is performed using angle-resolved C K-edge soft X-ray absorption spectroscopy (XAS) and model calculations. We find that our XAS measurements can be accurately related to the ground-state unoccupied orbitals using a simple crystal field model. We further find that films made by the one-step deposition protocol exhibit angle-dependent features, indicating long-range alignment of the CH3NH3 molecules, although the angle-dependency decreases as the film thickness increases. No angle-dependency was observed in the films made via the two-step deposition method.
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Affiliation(s)
- John A McLeod
- †Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
- ‡Soochow University-Western University Center for Synchrotron Radiation Research, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
| | - Zhongwei Wu
- †Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
| | - Pengfei Shen
- †Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
- ‡Soochow University-Western University Center for Synchrotron Radiation Research, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
| | - Baoquan Sun
- †Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
| | - Lijia Liu
- †Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
- ‡Soochow University-Western University Center for Synchrotron Radiation Research, 199 Ren'ai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, China
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Bai J, Liao L, Zhou H, Cheng R, Liu L, Huang Y, Duan X. Top-gated chemical vapor deposition grown graphene transistors with current saturation. Nano Lett 2011; 11:2555-9. [PMID: 21548551 PMCID: PMC3236244 DOI: 10.1021/nl201331x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Graphene transistors are of considerable interest for radio frequency (rf) applications. In general, transistors with large transconductance and drain current saturation are desirable for rf performance, which is however nontrivial to achieve in graphene transistors. Here we report high-performance top-gated graphene transistors based on chemical vapor deposition (CVD) grown graphene with large transconductance and drain current saturation. The graphene transistors were fabricated with evaporated high dielectric constant material (HfO(2)) as the top-gate dielectrics. Length scaling studies of the transistors with channel length from 5.6 μm to 100 nm show that complete current saturation can be achieved in 5.6 μm devices and the saturation characteristics degrade as the channel length shrinks down to the 100-300 nm regime. The drain current saturation was primarily attributed to drain bias induced shift of the Dirac points. With the selective deposition of HfO(2) gate dielectrics, we have further demonstrated a simple scheme to realize a 300 nm channel length graphene transistors with self-aligned source-drain electrodes to achieve the highest transconductance of 250 μS/μm reported in CVD graphene to date.
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Affiliation(s)
- Jingwei Bai
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095
| | - Lei Liao
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Hailong Zhou
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Rui Cheng
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095
| | - Lixin Liu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
| | - Yu Huang
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095
- California Nanosystems Institute, University of California, Los Angeles, CA 90095
- To whom correspondence should be addressed. ,
| | - Xiangfeng Duan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- California Nanosystems Institute, University of California, Los Angeles, CA 90095
- To whom correspondence should be addressed. ,
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