ISSN:0033-7579    

DOI:10.1080/00337577808233219

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The dechanneling width λ of a dislocation loop is a function of the diameter ϕ of the loop. From the expected behaviour of λ at small and large values of ϕ, an hyperbolic variation:is proposed both for axial and planar channeling. Values used for λ∞ are taken from Ref. 3.

ISSN:0033-7579    

DOI:10.1080/00337577808233220

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Nous présentons une méthode de calcul qui permet de determiner le nombre de défauts ponctuels créés dans une cascade de déplacements initiée par un ion lourd se ralentissant dans une cible diatomique. La méthode est utilisée pour déterminer le nombre d'atomes uranium et oxygéne places par une fission dans UO2.

ISSN:0033-7579    

DOI:10.1080/00337577808233221

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The ability of relevant current theories of secondary ion emission to explain experimental ion energy spectra obtained from polycrystalline Al, Sc, Ti, V, Cr, Fe, Ni, Cu, Hf, W and Au is analysed. It is shown that our present understanding or interpretation of the physics of the emission of secondary ions seems incapable of accounting for the observed changes in the energy spectra as a function of surface contamination or oxidation.

ISSN:0033-7579    

DOI:10.1080/00337577808233222

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The intensity distributions of low energy noble gas ions backscattered from single crystal surfaces have been simulated by a computer programme. Comparisons of computer studies with experiments for He+on W(110) and for Ne+on Ni(110) are presented and a focusing effect outlined. In the calculations the binary collision approximation with the Moliére and the Born-Mayer potentials were used. Thermal vibrations of the target atoms as well as neutralization and inelastic energy losses of the ions are included. The target may have any crystal- and any topographic surface-structure. Displacement of lattice atoms by ion collision is based on an energy-threshold criterion. The directions and the intensities of the backscattered ion trajectories are plotted in the Lambert azimuthal polar and in the stereographic equatorial projections. Ions reflected in specified solid angle regions can be selected for the plot of the relative kinetic ion energy as a function of the scattering angle and for the plot of the intensity as a function of the relative kinetic ion energy.

ISSN:0033-7579    

DOI:10.1080/00337577808233223

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

In order to study the behaviour of transitions between sites of heavy ions implanted in metals we have developed a general stochastic treatment. The outcome is a partial differential equation for the generating function of probabilities of site population numbers for anN-site model. This equation is solved for the two-site case both with irradiation terms and without, the resulting probability distributions are compared and their corresponding mean values and variances calculated. The deviations from Poisson behaviour are pointed out.

ISSN:0033-7579    

DOI:10.1080/00337577808233224

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The theory of relativistic electron and positron bremsstrahlung depending on the impact parameter has been developed on the basis of the virtual photon method. This theory is used to calculate bremsstrahlung under channelling conditions.

ISSN:0033-7579    

DOI:10.1080/00337577808233225

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A multisample consisting of two Cu samples and two samples of Cu alloyed with ∼ 100 ppm Au connected in series, was simultaneously irradiated with thermal neutrons at 4.2 K. The isochronal resistivity recovery of these samples was investigated from 30 K up to 400 K. Five different doses leading to about 0.5, 1, 3, 5 and 10 ppm initial defect concentrations at 4.2 K were used to investigate the dose dependence of the observed recovery stages. Several doping treatments and radiations at 80 K gave additional information on the processes responsible for some of the substages. The results for the alloyed Cu is compared with previous studies on Cu alloyed with different Au concentrations, but irradiated to one defect concentration only. This gives an independent check of trapping and detrapping mechanisms proposed for Stage II in Cu alloyed with Au. A recovery stage at ∼ 225 K, just below Stage III in Cu, which was reported to shift with increasing dose to lower temperatures could be resolved into two non-shifting substages with dose dependent relative heights.

ISSN:0033-7579    

DOI:10.1080/00337577808233226

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The irradiation of graphite single crystals with energetic helium ions reduces the magnitude of the diffraction effects observed in the angular distribution of X-ray photoelectrons. In spite of the negligible number of defects produced by the primary knock-ons, changes are produced within a surface layer of a thickness to be compared with the escape depth of the photoelectrons. The stress induced by damage located much deeper in the crystal is only partly relaxed at the surface. The lattice periodicity is disturbed even in the top most layers and the diffraction effects vanish accordingly.

ISSN:0033-7579    

DOI:10.1080/00337577808233227

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Extrinsic stacking faults generated in {100) n-type silicon wafers by random abrasion and subsequent steam oxidation have been utilized in distinguishing faulted from unfaulted loops after 35 keV boron implantation and annealing. Contrast changes from small faulted loops in the damaged layer are found to be identical with those observed in the pre-induced stacking faults during tilting in the transmission electron microscope. The technique permits faulted and unfaulted loops to be rapidly identified and distinguished, and their respective densities to be accurately measured.

ISSN:0033-7579    

DOI:10.1080/00337577808233228

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor