Sputtering yields for light ions as a function of angle of incidence

AbstractWe report on the simulation of the growth and subsequent krypton ion polishing of thin molybdenum films, required for extreme ultraviolet multilayer mirror fabrication. We have used a comprehensive Molecular Dynamics (MD) code, principally enabling a simulation of the deposition, ion bombardment and annealing processes. Ion energies used are in the sub-keV range, and the ion angle of incidence is varied between 30 and 60 degrees off-normal.The effects of ion polishing on the surface roughness are discussed, as well as the increase in (surface) atom mobility. We also report data on sputtering yields, ion penetration depths, trapping, energy transfer and krypton implantation and saturation.The results are compared with TRIM results, and the relevance of MD and TRIM simulations for specific purposes is discussed. Also, the effects of short-time, high-temperature annealing of an amorphous film are investigated.

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Calculation of the sputtering coefficients of oxide films from the surface of a homogeneous material by medium-energy helium ions

Applied Physics ◽

10.51368/1996-0948-2021-4-59-64 ◽

2021 ◽

pp. 59-64

Author(s):

Vladimir Manukhin

Keyword(s):

Analytical Formula ◽

Homogeneous Material ◽

Medium Energy ◽

Simulation Data ◽

Two Component ◽

Light Ions ◽

Calculation Results ◽

Computer Simulation Data ◽

Sputtering Yields ◽

Good Agreement

The paper presents an analytical model for sputtering two-component layered inhomogeneous targets by bombardment with light ions. An analytical formula is obtained that makes it possible to calculate the total and partial sputtering yields of a binary layer of target inhomogeneity by light ions. The obtained formula is used to calculate the sputtering yields of oxide layers from the surface of a homogeneous substrate. The calculation results are in good agreement with the computer simulation data.

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Electron Channeling Patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077700 ◽

1977 ◽

Vol 35 ◽

pp. 12-13

Author(s):

David C. Joy

Keyword(s):

Electron Diffraction ◽

Incidence Angle ◽

Photographic Plate ◽

Diffraction Effect ◽

Angle Of Incidence ◽

Bulk Single Crystal ◽

Time Resolved ◽

Electron Channeling ◽

Spatially Resolved ◽

Large Bulk

Electron channeling patterns (ECP) were first found by Coates (1967) while observing a large bulk, single crystal of silicon in a scanning electron microscope. The geometric pattern visible was shown to be produced as a result of the changes in the angle of incidence, between the beam and the specimen surface normal, which occur when the sample is examined at low magnification (Booker, Shaw, Whelan and Hirsch 1967).A conventional electron diffraction pattern consists of an angularly resolved intensity distribution in space which may be directly viewed on a fluorescent screen or recorded on a photographic plate. An ECP, on the other hand, is produced as the result of changes in the signal collected by a suitable electron detector as the incidence angle is varied. If an integrating detector is used, or if the beam traverses the surface at a fixed angle, then no channeling contrast will be observed. The ECP is thus a time resolved electron diffraction effect. It can therefore be related to spatially resolved diffraction phenomena by an application of the concepts of reciprocity (Cowley 1969).

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Electron-Channelling Patterns: Principles and Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100091986 ◽

1976 ◽

Vol 34 ◽

pp. 400-401

Author(s):

David C. Joy

Keyword(s):

Crystal Structure ◽

Electron Flux ◽

Lattice Structure ◽

Incident Beam ◽

Bloch Wave ◽

Crystalline Solid ◽

Angle Of Incidence ◽

Electron Channelling ◽

Regular Arrangement ◽

Backscattered Signals

In a crystalline solid the regular arrangement of the lattice structure influences the interaction of the incident beam with the specimen, leading to changes in both the transmitted and backscattered signals when the angle of incidence of the beam to the specimen is changed. For the simplest case the electron flux inside the specimen can be visualized as the sum of two, standing wave distributions of electrons (Fig. 1). Bloch wave 1 is concentrated mainly between the atom rows and so only interacts weakly with them. It is therefore transmitted well and backscattered weakly. Bloch wave 2 is concentrated on the line of atom centers and is therefore transmitted poorly and backscattered strongly. The ratio of the excitation of wave 1 to wave 2 varies with the angle between the incident beam and the crystal structure.

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The Microstructure of Steatite (Protoenstatite)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118102 ◽

1985 ◽

Vol 43 ◽

pp. 236-237

Author(s):

W. E. Lee ◽

A. H. Heuer

Keyword(s):

High Frequency ◽

Glass Ceramics ◽

Magnesium Silicate ◽

Beam Current ◽

Glassy Matrix ◽

Angle Of Incidence ◽

X Ray ◽

Mechanical And Electrical Properties ◽

Argon Ions ◽

High Temperature Polymorph

IntroductionTraditional steatite ceramics, made by firing (vitrifying) hydrous magnesium silicate, have long been used as insulators for high frequency applications due to their excellent mechanical and electrical properties. Early x-ray and optical analysis of steatites showed that they were composed largely of protoenstatite (MgSiO3) in a glassy matrix. Recent studies of enstatite-containing glass ceramics have revived interest in the polymorphism of enstatite. Three polymorphs exist, two with orthorhombic and one with monoclinic symmetry (ortho, proto and clino enstatite, respectively). Steatite ceramics are of particular interest a they contain the normally unstable high-temperature polymorph, protoenstatite.Experimental3mm diameter discs cut from steatite rods (∼10” long and 0.5” dia.) were ground, polished, dimpled, and ion-thinned to electron transparency using 6KV Argon ions at a beam current of 1 x 10-3 A and a 12° angle of incidence. The discs were coated with carbon prior to TEM examination to minimize charging effects.

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