Computer studies on bombarding-angle dependence of threshold energy of sputtering yields

ABSTRACTSputtering yields Y(E)at ion energies E keV are shown to be described by the equation Y(E) = A(En - ) where A, n, and the threshold energy Eth are constants characteristic for a particular projectile/target combination. Examination of a wide variety of systems reveals that n = 0.5 provides an excellent universal representation of a large body of data, including physical sputtering of metals by noble gas ions, selfsputtering of metals, as well as physical and chemical sputtering of Si and SiO2. The above value for n is consistent with a 1/r4 power law atom-atom interaction potential within Sigmund's theory of sputtering. Another conclusion is that the effect of Eth on Y(E) must be taken into account at ion energies as high as 1 keV, not just near the sputtering threshold.

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Sputtering of cobalt and chromium by argon and xenon ions near the threshold energy region

Canadian Journal of Physics ◽

10.1139/p93-024 ◽

1993 ◽

Vol 71 (3-4) ◽

pp. 155-158 ◽

Cited By ~ 3

Author(s):

A. K. Handoo ◽

P. K. Ray

Keyword(s):

Quantitative Measurement ◽

Threshold Energy ◽

Radioactive Tracer ◽

Tracer Technique ◽

Linear Extrapolation ◽

Radioactive Tracer Technique ◽

Ion Energies ◽

Sputtering Yield ◽

Sputtering Yields ◽

Threshold Energies

Sputtering yields of cobalt and chromium by argon and xenon ions with energies below 50 eV are reported. The targets were electroplated on copper substrates. Measurable sputtering yields were obtained from cobalt with ion energies as low as 10 eV. The ion beams were produced by an ion gun. A radioactive tracer technique was used for the quantitative measurement of the sputtering yield.57Co and 51Cr were used as tracers. The yield–energy curves are observed to be concave, which brings into question the practice of finding threshold energies by linear extrapolation.

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Angle Dependence of Argon Gas Cluster Sputtering Yields for Organic Materials

The Journal of Physical Chemistry B ◽

10.1021/jp512379k ◽

2015 ◽

Vol 119 (7) ◽

pp. 3297-3303 ◽

Cited By ~ 15

Author(s):

M. P. Seah ◽

S. J. Spencer ◽

A. G. Shard

Keyword(s):

Organic Materials ◽

Argon Gas ◽

Angle Dependence ◽

Sputtering Yields

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The bombarding-angle dependence of sputtering yields under various surface conditions

Radiation Effects ◽

10.1080/00337578708221239 ◽

1987 ◽

Vol 103 (1-4) ◽

pp. 25-43 ◽

Cited By ~ 31

Author(s):

Y. Yamamura ◽

C. Mössner ◽

H. Oechsner

Keyword(s):

Surface Conditions ◽

Angle Dependence ◽

Sputtering Yields

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Molecular dynamics simulation analyses on injection angle dependence of SiO2 sputtering yields by fluorocarbon beams

Thin Solid Films ◽

10.1016/j.tsf.2006.10.024 ◽

2007 ◽

Vol 515 (12) ◽

pp. 4883-4886 ◽

Cited By ~ 13

Author(s):

Tomohito Kawase ◽

Satoshi Hamaguchi

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Dynamics Simulation ◽

Injection Angle ◽

Angle Dependence ◽

Sputtering Yields

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Scattering-angle dependence of signal/background ratio of inner-shell electron excitation loss in EELS

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075701 ◽

1983 ◽

Vol 41 ◽

pp. 390-391

Author(s):

T. Oikawa ◽

M. Inoue ◽

T. Honda ◽

Y. Kokubo

Keyword(s):

Energy Loss ◽

Electron Excitation ◽

Heavy Elements ◽

Background Intensity ◽

Light Elements ◽

Energy Analyzer ◽

High Background ◽

Scattering Angle ◽

Angle Dependence ◽

Shell Electron

EELS allows us to make analysis of light elements such as hydrogen to heavy elements of microareas on the specimen. In energy loss spectra, however, elemental signals ride on a high background; therefore, the signal/background (S/B) ratio is very low in EELS. A technique which collects the center beam axial-symmetrically in the scattering angle is generally used to obtain high total intensity. However, the technique collects high background intensity together with elemental signals; therefore, the technique does not improve the S/B ratio. This report presents the experimental results of the S/B ratio measured as a function of the scattering angle and shows the possibility of the S/B ratio being improved in the high scattering angle range.Energy loss spectra have been measured using a JEM-200CX TEM with an energy analyzer ASEA3 at 200 kV.Fig.l shows a typical K-shell electron excitation edge riding on background in an energy loss spectrum.

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Anisotropy of damage productions in electron irradiated molybdenum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010010891x ◽

1978 ◽

Vol 36 (1) ◽

pp. 354-355

Author(s):

K. Izui ◽

S. Furuno ◽

H. Otsu ◽

T. Nishida ◽

H. Maeta

Keyword(s):

Electron Flux ◽

Threshold Energy ◽

High Energy ◽

Voltage Electron ◽

High Voltage Electron Microscope ◽

Displacement Threshold ◽

The Mean ◽

Channeling Effect ◽

Different Origins ◽

Threshold Energies

Anisotropy of damage productions in crystals due to high energy electron bombardment are caused from two different origins. One is an anisotropic displacement threshold energy, and the other is an anisotropic distribution of electron flux near the atomic rows in crystals due to the electron channeling effect. By the n-beam dynamical calculations for germanium and molybdenum we have shown that electron flux at the atomic positions are from ∽4 to ∽7 times larger than the mean incident flux for the principal zone axis directions of incident 1 MeV electron beams, and concluded that such a locally increased electron flux results in an enhanced damage production. The present paper reports the experimental evidence for the enhanced damage production due to the locally increased electron flux and also the results of measurements of the displacement threshold energies for the <100>,<110> and <111> directions in molybdenum crystals by using a high voltage electron microscope.

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The threshold energy for atom displacement in fcc metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175788 ◽

1990 ◽

Vol 48 (4) ◽

pp. 530-531

Author(s):

Wilfried Sigle ◽

Matthias Hohenstein ◽

Alfred Seeger

Keyword(s):

Growth Rate ◽

Elevated Temperatures ◽

Threshold Energy ◽

Dislocation Loops ◽

Absolute Minimum ◽

Voltage Electron ◽

Atom Displacement ◽

Electron Microscopes ◽

Fcc Metal

Prolonged electron irradiation of metals at elevated temperatures usually leads to the formation of large interstitial-type dislocation loops. The growth rate of the loops is proportional to the total cross-section for atom displacement,which is implicitly connected with the threshold energy for atom displacement, Ed . Thus, by measuring the growth rate as a function of the electron energy and the orientation of the specimen with respect to the electron beam, the anisotropy of Ed can be determined rather precisely. We have performed such experiments in situ in high-voltage electron microscopes on Ag and Au at 473K as a function of the orientation and on Au as a function of temperature at several fixed orientations.Whereas in Ag minima of Ed are found close to <100>,<110>, and <210> (13-18eV), (Fig.1) atom displacement in Au requires least energy along <100>(15-19eV) (Fig.2). Au is thus the first fcc metal in which the absolute minimum of the threshold energy has been established not to lie in or close to the <110> direction.

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