Structurally Controlled Large-Area 10 nm Pitch Graphene Nanomesh by Focused Helium Ion Beam Milling

This paper demonstrates that the electrical properties of suspended graphene nanomesh (GNM) can be tuned by systematically changing the porosity with helium ion beam milling (HIBM). The porosity of the GNM is well-controlled by defining the pitch of the periodic nanopores. The defective region surrounding the individual nanopores after HIBM, which limits the minimum pitch achievable between nanopores for a certain dose, is investigated and reported. The exponential relationship between the thermal activation energy (EA) and the porosity is found in the GNM devices. Good EA tuneability observed from the GNMs provides a new approach to the transport gap engineering beyond the conventional nanoribbon method.

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Thermal rectification on asymmetric suspended graphene nanomesh devices

Nano Futures ◽

10.1088/2399-1984/ac36b5 ◽

2021 ◽

Author(s):

Fayong Liu ◽

Manoharan Muruganathan ◽

Yu Feng ◽

Shinichi Ogawa ◽

Yukinori Morita ◽

...

Keyword(s):

Thermal Transport ◽

High Performance ◽

Ion Beam ◽

Phononic Crystal ◽

Rectification Ratio ◽

Suspended Graphene ◽

Thermal Rectification ◽

Helium Ion ◽

Graphene Nanomesh ◽

20 Nm

Abstract The graphene-based thermal rectification is investigated by measuring the thermal transport properties on asymmetric suspended graphene nanomesh devices. Sub-10 nm periodic nanopore phononic crystal structure is successfully patterned on the half area of the suspended graphene by the helium ion beam milling technology. The “differential thermal leakage” method is developed for thermal transport measurement without being disturbed by the electron current leakage through the suspended graphene bridge. Up to 60 % thermal rectification ratio is observed in a typical device with a nanopore pitch of 20 nm. By increasing the nanopore pitch in a particular range, the thermal rectification ratio shows an increment. However, this ratio is degraded by increasing the environmental temperature. This experiment preliminary shows a promising way to develop a high-performance thermal rectifier by using a phononic crystal to introduce the asymmetry on homogenous material.

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Large-Scale Focused Helium Ion Beam Lithography

IEEE Transactions on Applied Superconductivity ◽

10.1109/tasc.2021.3057324 ◽

2021 ◽

Vol 31 (5) ◽

pp. 1-4

Author(s):

Jay C. LeFebvre ◽

Shane A. Cybart

Keyword(s):

Large Scale ◽

Ion Beam ◽

Ion Beam Lithography ◽

Helium Ion

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Large Area Surface Treatment by Ion Beam Technology

MRS Proceedings ◽

10.1557/proc-438-611 ◽

1996 ◽

Vol 438 ◽

Cited By ~ 2

Author(s):

R. L. C. Wu ◽

W. Lanter

Keyword(s):

Ion Beam ◽

High Vacuum ◽

Polycrystalline Diamond ◽

Carbon Films ◽

Ultra High Vacuum ◽

Diamond Like Carbon ◽

Chemical Compositions ◽

Rf Power ◽

Large Area ◽

Ion Energy

AbstractAn ultra high vacuum ion beam system, consisting of a 20 cm diameter Rf excilted (13.56 MHz) ion gun and a four-axis substrate scanner, has been used to modify large surfaces (up to 1000 cm2) of various materials, including; infrared windows, silicon nitride, polycrystalline diamond, 304 and 316 stainless steels, 440C and M50 steels, aluminum alloys, and polycarbonates; by depositing different chemical compositions of diamond-like carbon films. The influences of ion energy, Rf power, gas composition (H2/CH4 , Ar/CH4 and O2/CH4/H2), on the diamond-like carbon characteristics has been studied. Particular attention was focused on adhesion, environmental effects, IR(3–12 μm) transmission, coefficient of friction, and wear factors under spacelike environments of diamond-like carbon films on various substrates. A quadrupole mass spectrometer was utilized to monitor the ion beam composition for quality control and process optimization.

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Large Area Photonic Crystal Slabs for Visible Light with Waveguiding Defect Structures: Fabrication with Focused Ion Beam Assisted Laser Interference Lithography

Advanced Materials ◽

10.1002/1521-4095(200110)13:20<1551::aid-adma1551>3.0.co;2-v ◽

2001 ◽

Vol 13 (20) ◽

pp. 1551 ◽

Cited By ~ 52

Author(s):

L. Vogelaar ◽

W. Nijdam ◽

H. A. G. M. van Wolferen ◽

R. M. de Ridder ◽

F. B. Segerink ◽

...

Keyword(s):

Photonic Crystal ◽

Visible Light ◽

Focused Ion Beam ◽

Ion Beam ◽

Interference Lithography ◽

Laser Interference Lithography ◽

Defect Structures ◽

Laser Interference ◽

Large Area ◽

Photonic Crystal Slabs

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Formation of a large-area uniform ion beam using multipole magnets in the TIARA cyclotron

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2011.03.055 ◽

2011 ◽

Vol 642 (1) ◽

pp. 10-17 ◽

Cited By ~ 14

Author(s):

Yosuke Yuri ◽

Tomohisa Ishizaka ◽

Takahiro Yuyama ◽

Ikuo Ishibori ◽

Susumu Okumura ◽

...

Keyword(s):

Ion Beam ◽

Large Area

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Narrow conducting channels defined by helium ion beam damage

Applied Physics Letters ◽

10.1063/1.100337 ◽

1988 ◽

Vol 53 (20) ◽

pp. 1964-1966 ◽

Cited By ~ 35

Author(s):

T. L. Cheeks ◽

M. L. Roukes ◽

A. Scherer ◽

H. G. Craighead

Keyword(s):

Ion Beam ◽

Helium Ion ◽

Beam Damage

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Scanning transmission imaging in the helium ion microscope using a microchannel plate with a delay line detector

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.11.167 ◽

2020 ◽

Vol 11 ◽

pp. 1854-1864

Author(s):

Eduardo Serralta ◽

Nico Klingner ◽

Olivier De Castro ◽

Michael Mousley ◽

Santhana Eswara ◽

...

Keyword(s):

Delay Line ◽

Ion Beam ◽

Microchannel Plate ◽

Wide Energy Range ◽

High Angle ◽

Data Set ◽

Beam Position ◽

Angle Scattering ◽

Helium Ion ◽

Scanning Transmission

A detection system based on a microchannel plate with a delay line readout structure has been developed to perform scanning transmission ion microscopy (STIM) in the helium ion microscope (HIM). This system is an improvement over other existing approaches since it combines the information of the scanning beam position on the sample with the position (scattering angle) and time of the transmission events. Various imaging modes, such as bright field and dark field or the direct image of the transmitted signal, can be created by post-processing the collected STIM data. Furthermore, the detector has high spatial and temporal resolution, is sensitive to both ions and neutral particles over a wide energy range, and shows robustness against ion beam-induced damage. A special in-vacuum movable support gives the possibility of moving the detector vertically, placing the detector closer to the sample for the detection of high-angle scattering events, or moving it down to increase the angular resolution and distance for time-of-flight measurements. With this new system, we show composition-dependent contrast for amorphous materials and the contrast difference between small-angle and high-angle scattering signals. We also detect channeling-related contrast on polycrystalline silicon, thallium chloride nanocrystals, and single-crystalline silicon by comparing the signal transmitted at different directions for the same data set.

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