Scanning electron imaging with vertically aligned carbon nanotube (CNT) based cold cathode electron beam (C-beam)

Lee, Ha Rim; Kim, Da-Woon; Hwang, Ok Jung; Cho, Boklae; Park, Kyu Chang

doi:10.1016/j.vacuum.2020.109696

Cited by 21 publications

(31 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After the forming process, CNTs are grown in the DC-PECVD system, and the emitter structure can be adjusted according to the growing conditions. Several parameters determine the structure of a CNT cold cathode: seed size, temperature, pressure, plasma current, and gas ratio [ 27 ]. These growing conditions are listed in Table 1 .…”

Section: Methodsmentioning

confidence: 99%

Investigation of the Effect of Structural Properties of a Vertically Standing CNT Cold Cathode on Electron Beam Brightness and Resolution of Secondary Electron Images

et al. 2021

Self Cite

View full text Add to dashboard Cite

Carbon nanotube (CNT)-based cold cathodes are promising sources of field emission electrons for advanced electron devices, particularly for ultra-high-resolution imaging systems, due to their high brightness and low energy spread. While the electron field emission properties of single-tip CNT cathodes have been intensively studied in the last few decades, a systematic study of the influencing factors on the electron beam properties of CNT cold cathodes and the resolution of the secondary electron images has been overlooked in this field. Here, we have systematically investigated the effect of the structural properties of a CNT cold cathode on the electron beam properties and resolution of secondary electron microscope (SEM) images. The aspect ratio (geometric factor) and the diameter of the tip of a vertically standing CNT cold cathode significantly affect the electron beam properties, including the beam size and brightness, and consequently determine the resolution of the secondary electron images obtained by SEM systems equipped with a CNT cold cathode module. Theoretical simulation elucidated the dependence of the structural features of CNT cold cathodes and electron beam properties on the contribution of edge-emitted electrons to the total field emission current. Investigating the correlations between the structural properties of CNT cold cathodes, the properties of the emitted electron beams, and the resolution of the secondary electron images captured by SEM equipped with CNT cold cathode modules is highly important and informative as a basic model.

show abstract

Section: Methodsmentioning

confidence: 99%

Investigation of the Effect of Structural Properties of a Vertically Standing CNT Cold Cathode on Electron Beam Brightness and Resolution of Secondary Electron Images

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Battery electrode additives (MWCNT) [38] Composites (sporting goods; MWCNT) [3,318] Composites (Electrostatic discharge (ESD) applications; MWCNT) [150,151] Scanning probe tips (MWCNT) [209] Specialized medical appliances (catheters) (MWCNT) [74] Near term (less than 10 years) Battery and super-capacitor electrodes [254] Multifunctional composites (3D, damping) [91,287] Fuel-cell electrodes (catalyst support) [37] Transparent conducting films [337,338] Field emission displays/lighting-CNT-based inks for printing [252] Atomic force microscope (AFM) tip [60] Electrochemical energy storage and production [51] Single-tip electron guns [173] Multi-tip array X-ray sources [206] Probe array test systems [45] CNT brush contacts [46] CNT sensor devices [358,360] Electromechanical switches [268] and the memory device [334] Thermal-management systems [114] CNTs as carrier substance in energy applications (heterogenic catalysis) [227] Long term (beyond 10 years) Power transmission cables [125] Structural composites (aerospace and automobile, etc.) [22] CNT in photovoltaic devices [237] Space elevator [219] CNT in vacuum Microelectronics [4] Nanoelectronics (field-effect transistor (FET), interconnects) [8,358] Flexible electronics [156] CNT-based biosensors [323] CNT fitration/separation membranes [346,347] Drug-delivery systems…”

Section: Presentmentioning

confidence: 99%

A Review on Fracture Analysis of CNT/Graphene Reinforced Composites for Structural Applications

Yadav

Godara

Bhardwaj

et al. 2021

Arch Computat Methods Eng

View full text Add to dashboard Cite

CNT/Graphene reinforced composites due to their exceptional mechanical, electrical, thermal, and optical characteristics that have attracted the scientific community working in the area of material development. In protraction, this review work on fracture analysis of CNT/Graphene reinforced composites is summarized from an exponentially growing literature inclusive of fabrication methods and present and potential applications. Owing to these composites' enormous structural applications, the number of literature works on the fracture of the structures using various models is summarized here. The literature contains several techniques to model the CNT/graphene composites that include: Halpin Tsai model, modified Halpin Tsai model, Mori-Tanaka model, homogenization approach, etc. which are discussed in detail. Various combined analysis for fracture toughness and crack growth analysis based on fracture mechanics are cited here using different computational formulations like finite element method (FEM), element free Galerkin method, reproducing kernel particle method, meshless local Petrov-Galerkin method, extended finite element method (XFEM), isogeometric analysis (IGA), etc. In particular, the authors have reported the work done in the area of fracture analysis of these novel composites since its inception that is inclusive of its structure, fabrication, properties, mathematical modeling, applications, and analysis.

show abstract

“…The significant improvement was important for high current density, high resolution, high brightness, and low energy spread [ 1 , 2 , 3 ]. Considerable attention was paid to the development of the electron source for electron beam microscopy [ 4 , 5 , 6 , 7 , 8 , 9 ]. In recent years, carbon nanotubes (CNTs) have been considered field emission (FE) materials because they have remarkable properties such as high aspect ratio [ 10 ], high electrical conductivity [ 9 , 11 ], high thermal conductivity [ 12 , 13 ], and high mechanical strength [ 14 ], which make them extremely attractive as nanoscale reinforcements in high-performance composites.…”

Section: Introductionmentioning

confidence: 99%

“…Considerable attention was paid to the development of the electron source for electron beam microscopy [ 4 , 5 , 6 , 7 , 8 , 9 ]. In recent years, carbon nanotubes (CNTs) have been considered field emission (FE) materials because they have remarkable properties such as high aspect ratio [ 10 ], high electrical conductivity [ 9 , 11 ], high thermal conductivity [ 12 , 13 ], and high mechanical strength [ 14 ], which make them extremely attractive as nanoscale reinforcements in high-performance composites. These properties have made CNTs a promising tip material for electron microscopy, e.g., scanning electron microscopy (SEM) [ 9 ] and atomic force microscopy [ 15 ].…”

Section: Introductionmentioning

confidence: 99%

Beam Trajectory Analysis of Vertically Aligned Carbon Nanotube Emitters with a Microchannel Plate

et al. 2022

Self Cite

View full text Add to dashboard Cite

Vertically aligned carbon nanotubes (CNTs) are essential to studying high current density, low dispersion, and high brightness. Vertically aligned 14 × 14 CNT emitters are fabricated as an island by sputter coating, photolithography, and the plasma-enhanced chemical vapor deposition process. Scanning electron microscopy is used to analyze the morphology structures with an average height of 40 µm. The field emission microscopy image is captured on the microchannel plate (MCP). The role of the microchannel plate is to determine how the high-density electron beam spot is measured under the variation of voltage and exposure time. The MCP enhances the field emission current near the threshold voltage and protects the CNT from irreversible damage during the vacuum arc. The high-density electron beam spot is measured with an FWHM of 2.71 mm under the variation of the applied voltage and the exposure time, respectively, which corresponds to the real beam spot. This configuration produces the beam trajectory with low dispersion under the proper field emission, which could be applicable to high-resolution multi-beam electron microscopy and high-resolution X-ray imaging technology.

show abstract

Scanning electron imaging with vertically aligned carbon nanotube (CNT) based cold cathode electron beam (C-beam)

Cited by 21 publications

References 30 publications

Investigation of the Effect of Structural Properties of a Vertically Standing CNT Cold Cathode on Electron Beam Brightness and Resolution of Secondary Electron Images

Investigation of the Effect of Structural Properties of a Vertically Standing CNT Cold Cathode on Electron Beam Brightness and Resolution of Secondary Electron Images

A Review on Fracture Analysis of CNT/Graphene Reinforced Composites for Structural Applications

Beam Trajectory Analysis of Vertically Aligned Carbon Nanotube Emitters with a Microchannel Plate

Contact Info

Product

Resources

About