scholarly journals Ion beam profiling from the interaction with a freestanding 2D layer

2017 ◽  
Vol 8 ◽  
pp. 682-687 ◽  
Author(s):  
Ivan Shorubalko ◽  
Kyoungjun Choi ◽  
Michael Stiefel ◽  
Hyung Gyu Park
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Current ◽  
Exposure Dose ◽  
Ion Beams ◽  
Gaussian Profile ◽  
Helium Ion ◽  
Spread Function ◽  
Sputtering Yields ◽  
Pattern Resolution

Recent years have seen a great potential of the focused ion beam (FIB) technology for the nanometer-scale patterning of a freestanding two-dimensional (2D) layer. Experimentally determined sputtering yields of the perforation process can be quantitatively explained using the binary collision theory. The main peculiarity of the interaction between the ion beams and the suspended 2D material lies in the absence of collision cascades, featured by no interaction volume. Thus, the patterning resolution is directly set by the beam diameters. Here, we demonstrate pattern resolution beyond the beam size and precise profiling of the focused ion beams. We find out that FIB exposure time of individual pixels can influence the resultant pore diameter. In return, the pore dimension as a function of the exposure dose brings out the ion beam profiles. Using this method of determining an ion-beam point spread function, we verify a Gaussian profile of focused gallium ion beams. Graphene sputtering yield is extracted from the normalization of the measured Gaussian profiles, given a total beam current. Interestingly, profiling of unbeknown helium ion beams in this way results in asymmetry of the profile. Even triangular beam shapes are observed at certain helium FIB conditions, possibly attributable to the trimer nature of the beam source. Our method of profiling ion beams with 2D-layer perforation provides more information on ion beam profiles than the conventional sharp-edge scan method does.

scholarly journals Imaging and milling resolution of light ion beams from helium ion microscopy and FIBs driven by liquid metal alloy ion sources

2020 ◽  
Vol 11 ◽  
pp. 1742-1749
Author(s):  
Nico Klingner ◽  
Gregor Hlawacek ◽  
Paul Mazarov ◽  
Wolfgang Pilz ◽  
Fabian Meyer ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Ion Beams ◽  
Ion Source ◽  
Metal Alloy ◽  
Gas Field ◽  
Helium Ion ◽  
Liquid Metal Alloy ◽  
Ion Species

While the application of focused ion beam (FIB) techniques has become a well-established technique in research and development for patterning and prototyping on the nanometer scale, there is still a large underused potential with respect to the usage of ion species other than gallium. Light ions in the range of m = 1–28 u (hydrogen to silicon) are of increasing interest due to the available high beam resolution in the nanometer range and their special chemical and physical behavior in the substrate. In this work, helium and neon ion beams from a helium ion microscope are compared with ion beams such as lithium, beryllium, boron, and silicon, obtained from a mass-separated FIB using a liquid metal alloy ion source (LMAIS) with respect to the imaging and milling resolution, as well as the current stability. Simulations were carried out to investigate whether the experimentally smallest ion-milled trenches are limited by the size of the collision cascade. While He+ offers, experimentally and in simulations, the smallest minimum trench width, light ion species such as Li+ or Be+ from a LMAIS offer higher milling rates and ion currents while outperforming the milling resolution of Ne+ from a gas field ion source. The comparison allows one to select the best possible ion species for the specific demands in terms of resolution, beam current, and volume to be drilled.

scholarly journals Direct Write of 3D Nanoscale Mesh Objects with Platinum Precursor via Focused Helium Ion Beam Induced Deposition

Micromachines ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 527
Author(s):  
Alex Belianinov ◽  
Matthew J. Burch ◽  
Anton Ievlev ◽  
Songkil Kim ◽  
Michael G. Stanford ◽  
...  
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Current ◽  
Ion Source ◽  
Direct Write ◽  
Gas Field ◽  
Critical Dimensions ◽  
3D Mesh ◽  
Nanoscale Structures ◽  
Helium Ion

The next generation optical, electronic, biological, and sensing devices as well as platforms will inevitably extend their architecture into the 3rd dimension to enhance functionality. In focused ion beam induced deposition (FIBID), a helium gas field ion source can be used with an organometallic precursor gas to fabricate nanoscale structures in 3D with high-precision and smaller critical dimensions than focused electron beam induced deposition (FEBID), traditional liquid metal source FIBID, or other additive manufacturing technology. In this work, we report the effect of beam current, dwell time, and pixel pitch on the resultant segment and angle growth for nanoscale 3D mesh objects. We note subtle beam heating effects, which impact the segment angle and the feature size. Additionally, we investigate the competition of material deposition and sputtering during the 3D FIBID process, with helium ion microscopy experiments and Monte Carlo simulations. Our results show complex 3D mesh structures measuring ~300 nm in the largest dimension, with individual features as small as 16 nm at full width half maximum (FWHM). These assemblies can be completed in minutes, with the underlying fabrication technology compatible with existing lithographic techniques, suggesting a higher-throughput pathway to integrating FIBID with established nanofabrication techniques.

Nano-engineering with a focused helium ion beam

2011 ◽  
Vol 1354 ◽  
Author(s):  
Diederik J. Maas ◽  
Emile W. van der Drift ◽  
Emile van Veldhoven ◽  
Jeroen Meessen ◽  
Maria Rudneva ◽  
...  
Keyword(s):  
High Resolution ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Current ◽  
Helium Ion ◽  
Resolution Imaging ◽  
Application Fields ◽  
Analysis Mode ◽  
Novel Applications ◽  
Ion Backscattering

ABSTRACTAlthough Helium Ion Microscopy (HIM) was introduced only a few years ago, many new application fields are budding. The connecting factor between these novel applications is the unique interaction of the primary helium ion beam with the sample material at and just below its surface. In particular, the HIM secondary electron (SE) signal stems from an area that is very well localized around the point of incidence of the primary beam. This makes the HIM well-suited for both high-resolution imaging as well as high resolution nanofabrication. Another advantage in nanofabrication is the low ion backscattering fraction, leading to a weak proximity effect. The lack of a quantitative materials analysis mode (like EDX in Scanning Electron Microscopy, SEM) and a relatively low beam current as compared to the SEM and the Gallium Focused Ion Beam are the present drawbacks of the HIM.

Fabrication of large area nanogap electrodes for sensing applications

2013 ◽  
Vol 1530 ◽  
Author(s):  
A. Bendavid ◽  
L. Wieczorek ◽  
R. Chai ◽  
J. S. Cooper ◽  
B. Raguse
Keyword(s):  
Large Scale ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Beam Current ◽  
Fabrication Method ◽  
Large Area ◽  
Sensor Applications ◽  
Sensing Applications ◽  
Lift Off ◽  
Nanogap Electrodes

ABSTRACTA large area nanogap electrode fabrication method combinig conventional lithography patterning with the of focused ion beam (FIB) is presented. Lithography and a lift-off process were used to pattern 50 nm thick platinum pads having an area of 300 μm × 300 μm. A range of 30-300 nm wide nanogaps (length from 300 μm to 10 mm ) were then etched using an FIB of Ga+ at an acceleration voltage of 30 kV at various beam currents. An investigation of Ga+ beam current ranging between 1-50 pA was undertaken to optimise the process for the current fabrication method. In this study, we used Monte Carlo simulation to calculate the damage depth in various materials by the Ga+. Calculation of the recoil cascades of the substrate atoms are also presented. The nanogap electrodes fabricated in this study were found to have empty gap resistances exceeding several hundred MΩ. A comparison of the gap length versus electrical resistance on glass substrates is presented. The results thus outline some important issues in low-conductance measurements. The proposed nanogap fabrication method can be extended to various sensor applications, such as chemical sensing, that employ the nanogap platform. This method may be used as a prototype technique for large-scale fabrication due to its simple, fast and reliable features.

Characterization of FIB Damage in Silicon

1999 ◽  
Vol 5 (S2) ◽  
pp. 740-741 ◽  
Author(s):  
C.A. Urbanik ◽  
B.I. Prenitzer ◽  
L.A. Gianhuzzi ◽  
S.R. Brown ◽  
T.L. Shofner ◽  
...  
Keyword(s):  
Focused Ion Beam ◽  
Ion Beam ◽  
Target Material ◽  
Beam Current ◽  
Specimen Preparation ◽  
Transfer Energy ◽  
Transmission Electron ◽  
Preparation Techniques ◽  
Reactive Gas

Focused ion beam (FIB) instruments are useful for high spatial resolution milling, deposition, and imaging capabilities. As a result, FIB specimen preparation techniques have been widely accepted within the semiconductor community as a means to rapidly prepare high quality, site-specific specimens for transmission electron microscopy (TEM) [1]. In spite of the excellent results that have been observed for both high resolution (HREM) and standard TEM specimen preparation applications, a degree of structural modification is inherent to FIB milled surfaces [2,3]. The magnitude of the damage region that results from Ga+ ion bombardment is dependent on the operating parameters of the FIB (e.g., beam current, beam voltage, milling time, and the use of reactive gas assisted etching).Lattice defects occur as a consequence of FIB milling because the incident ions transfer energy to the atoms of the target material. Momentum transferred from the incident ions to the target atoms can result in the creation of point defects (e.g., vacancies, self interstitials, and interstitial and substitutional ion implantation), the generation of phonons, and plasmon excitation in the case of metal targets.

Quantitative Dopant Contrast in Scanning Electron Microscope and Helium Ion Microscope Using Focused Ion Beam Prepared Specimens

2012 ◽  
Vol 18 (S2) ◽  
pp. 820-821
Author(s):  
H. Zhang ◽  
Y. Chen
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Helium Ion ◽  
Scanning Electron

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Focused Ion Beam Metrology

1995 ◽  
Vol 396 ◽  
Author(s):  
A. Wagner ◽  
P. Blauner ◽  
P. Longo ◽  
S. Cohen
Keyword(s):  
Integrated Circuits ◽  
Cross Sections ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Dimensional Change ◽  
Critical Dimension ◽  
Ion Beams ◽  
Near Surface ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

AbstractFocused Ion Beams offer a new method of measuring the size of polymer resist features on integrated circuits. The short penetration range of an ion relative to an electron is shown to offer fundamental advantages for critical dimension (CD) metrology. By confining the polymer damage to the very near surface, ion beams can induce less dimensional change than scanning electron microscopes during the measurement process. This can result in improved CD measurement precision. The erosion rate of polymers to various ion species is also presented, and we show that erosion is non-linear with ion dose. The use of FIB for forming resist cross sections is also demonstrated. An H20 gas assisted etching process for polymers has been developed, and is shown to significantly improve the quality of resist cross sections.

Recent Advances in The Application of Focused Ion Beams

1985 ◽  
Vol 45 ◽  
Author(s):  
Kenji Gamo ◽  
Susumu Namba
Keyword(s):  
Ion Implantation ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Ion Beams ◽  
Focused Ion Beams ◽  
Ion Beam Modification ◽  
Chemical Effects ◽  
Recent Advances ◽  
Maskless Patterning

Recent advances of focused ion beam systems and their applications are presented. The applications include maskless ion implantation and various maskless patterning techniques which make use of ion induced chemical effects. These are ion beam assisted etching, deposition and ion beam modification techniques and are promising to improve patterning speed and extend applications of focused ion beams.

Nanostructures from Hydrogen and Helium Implantation of Aluminum

2010 ◽  
Vol 1264 ◽  
Author(s):  
Markus D. Ong ◽  
Nancy Yang ◽  
Ryan J. Depuit ◽  
Bruce R. McWatters ◽  
Rion A. Causey
Keyword(s):  
Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
High Mobility ◽  
Transmission Electron ◽  
Helium Ion ◽  
Fusion Applications ◽  
Helium Implantation ◽  
Bicontinuous Structure ◽  
Nanoporous Structures

AbstractThis study investigates a pathway to nanoporous structures created by hydrogen and helium implantation in aluminum. Previous experiments for fusion applications have indicated that hydrogen and helium ion implantations are capable of producing bicontinuous nanoporous structures in a variety of metals. This study focuses specifically on implantations of hydrogen and helium ions at 25 keV in aluminum. The hydrogen and helium systems result in remarkably different nanostructures of aluminum at the surface. Scanning electron microscopy, focused ion beam, and transmission electron microscopy show that both implantations result in porosity that persists approximately 200 nm deep. However, hydrogen implantations tend to produce larger and more irregular voids that preferentially reside at defects. Implantations of helium at a fluence of 1018 cm-2 produce much smaller porosity on the order of 10 nm that is regular and creates a bicontinuous structure in the porous region. The primary difference driving the formation of the contrasting structures is likely the relatively high mobility of hydrogen and the ability of hydrogen to form alanes that are capable of desorbing and etching Al (111) faces.

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