Abstract

Focused ion beams provide a means of nanometer-scale manufacturing and material processing, which is used for applications such as forming nanometer-scale pores in thin films for DNA sequencing. We investigate such a configuration with Ga+ bombardment of a Si thin-film target using molecular dynamics simulation. For a range of ion intensities in a realistic configuration, a recirculating melt region develops, which is seen to flow with a symmetrical pattern, counter to how it would flow were it driven by the ion momentum flux. Such flow is potentially important for the shape and composition of the formed structures. Relevant stress scales and estimated physical properties of silicon under these extreme conditions support the importance thermocapillary effects. A flow model with Marangoni forcing, based upon the temperature gradient and geometry from the atomistic simulation, indeed reproduces the flow and thus could be used to anticipate such flows and their influence in applications.

Original languageEnglish (US)
Article number1.4919782
JournalPhysics of fluids
Volume27
Issue number5
DOIs
StatePublished - May 12 2015

Fingerprint

Focused ion beams
ion beams
Thin films
Ions
Thermal gradients
Molecular dynamics
Momentum
DNA
Physical properties
Fluxes
Silicon
Geometry
Computer simulation
Processing
Chemical analysis
sequencing
thin films
configurations
bombardment
temperature gradients

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Atomic-scale thermocapillary flow in focused ion beam milling. / Das, K.; Johnson, Harley T; Freund, Jonathan.

In: Physics of fluids, Vol. 27, No. 5, 1.4919782, 12.05.2015.

Research output: Contribution to journalArticle

@article{7d39c2f273374b33a38ce1ac04b23d33,
title = "Atomic-scale thermocapillary flow in focused ion beam milling",
abstract = "Focused ion beams provide a means of nanometer-scale manufacturing and material processing, which is used for applications such as forming nanometer-scale pores in thin films for DNA sequencing. We investigate such a configuration with Ga+ bombardment of a Si thin-film target using molecular dynamics simulation. For a range of ion intensities in a realistic configuration, a recirculating melt region develops, which is seen to flow with a symmetrical pattern, counter to how it would flow were it driven by the ion momentum flux. Such flow is potentially important for the shape and composition of the formed structures. Relevant stress scales and estimated physical properties of silicon under these extreme conditions support the importance thermocapillary effects. A flow model with Marangoni forcing, based upon the temperature gradient and geometry from the atomistic simulation, indeed reproduces the flow and thus could be used to anticipate such flows and their influence in applications.",
author = "K. Das and Johnson, {Harley T} and Jonathan Freund",
year = "2015",
month = "5",
day = "12",
doi = "10.1063/1.4919782",
language = "English (US)",
volume = "27",
journal = "Physics of Fluids",
issn = "1070-6631",
publisher = "American Institute of Physics Publising LLC",
number = "5",

}

TY - JOUR

T1 - Atomic-scale thermocapillary flow in focused ion beam milling

AU - Das, K.

AU - Johnson, Harley T

AU - Freund, Jonathan

PY - 2015/5/12

Y1 - 2015/5/12

N2 - Focused ion beams provide a means of nanometer-scale manufacturing and material processing, which is used for applications such as forming nanometer-scale pores in thin films for DNA sequencing. We investigate such a configuration with Ga+ bombardment of a Si thin-film target using molecular dynamics simulation. For a range of ion intensities in a realistic configuration, a recirculating melt region develops, which is seen to flow with a symmetrical pattern, counter to how it would flow were it driven by the ion momentum flux. Such flow is potentially important for the shape and composition of the formed structures. Relevant stress scales and estimated physical properties of silicon under these extreme conditions support the importance thermocapillary effects. A flow model with Marangoni forcing, based upon the temperature gradient and geometry from the atomistic simulation, indeed reproduces the flow and thus could be used to anticipate such flows and their influence in applications.

AB - Focused ion beams provide a means of nanometer-scale manufacturing and material processing, which is used for applications such as forming nanometer-scale pores in thin films for DNA sequencing. We investigate such a configuration with Ga+ bombardment of a Si thin-film target using molecular dynamics simulation. For a range of ion intensities in a realistic configuration, a recirculating melt region develops, which is seen to flow with a symmetrical pattern, counter to how it would flow were it driven by the ion momentum flux. Such flow is potentially important for the shape and composition of the formed structures. Relevant stress scales and estimated physical properties of silicon under these extreme conditions support the importance thermocapillary effects. A flow model with Marangoni forcing, based upon the temperature gradient and geometry from the atomistic simulation, indeed reproduces the flow and thus could be used to anticipate such flows and their influence in applications.

UR - http://www.scopus.com/inward/record.url?scp=84929376839&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84929376839&partnerID=8YFLogxK

U2 - 10.1063/1.4919782

DO - 10.1063/1.4919782

M3 - Article

AN - SCOPUS:84929376839

VL - 27

JO - Physics of Fluids

JF - Physics of Fluids

SN - 1070-6631

IS - 5

M1 - 1.4919782

ER -