摘要:

Total current spectroscopy (TCS) has been used to probe the {100} surface of a single crystal of vanadium. Primary electron energies were in the range 0–10 eV.

ISSN:0033-7579    

DOI:10.1080/00337577608234773

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The paper analyzes the resistivity-versus-dose curves (damage curves) measured on platinum during light-ion or electron irradiation at various temperatures. The analysis is based on a generalization of Walker's unsaturable trap model that allows for the possibility of the existence of two distinct configurations of self-interstitials. The available data indicate clearly that in addition to the Stage IEinterstitial a second self-interstitial configuration exists, which begins to migrate freely at about 300 K. This result decides the controversy between Jackson on the one hand and van den Beukel and Schilling on the other hand on the labelling of recovery stages in platinum in favour of the former (i.e., the 300 K recovery should be named “Stage III”). Platinum belongs to the group of metals in which the existence of two self-interstitial configurations is established. The temperature of thermal conversion from the metastable (IE) to the stable (III) configuration is found to lie above 140 K.

ISSN:0033-7579    

DOI:10.1080/00337577608234774

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The paper presents a discussion of the recovery of the electrical resistivity of irradiated platinum. The available data support the two-interstitial model for platinum, in agreement with the deductions from the analysis of damage curves (Part I). It is shown that the tendency for interstitial clustering in platinum is stronger than in other fee metals. This explains why in Pt the free migration of the stable interstitial configuration in Stage III (300 K to 350 K) appears suppressed at high doses. Under these circumstances the low-temperature part (420 K to 550 K) of Stage IV is well developed. It is attributed to the decay of small interstitial clusters. An alternative interpretation of Sonnenberget al.is discussed in detail and is shown to be untenable.

ISSN:0033-7579    

DOI:10.1080/00337577608234775

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The scattering of 4–10 keV Helium ions from a copper surface can be described reasonably well with elastic, single collisions, even for fairly small scattering angles. However, in a more refined analysis of the experimental results, deviations from this behaviour are observed. Measurements of the energy and the width (FWHM) of the surface peak have been performed. The general behaviour can be explained by differences in inelastic energy losses for scattering from an ideal surface and from surface structures (surface damage). By comparing measurements in which the target is bombarded along different directions, it is shown that multiple scattering effects have only a minor influence. Additional information about the inelastic processes is obtained by performing scattering experiments with a primary atom beam. It appears that, for large angles of incidence, the energy of the reflected ions is reduced about 20 eV if the primary beam consists of atoms instead of ions. This difference is almost independent of the energy of the projectiles. An explanation of this effect is given by the charge exchange model, proposed previously by the authors. The model also explains the different behaviour at small angles of incidence. Indications were found which suggested that in the investigated energy range the electronic stopping power depends on the charge state of the primary particles. The results have been compared with the Lindhard theory. The agreement between our experiments and the LSS theory is rather good.

ISSN:0033-7579    

DOI:10.1080/00337577608234776

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The variations of both the linewidth δH[G] of the conduction electron spin resonance (CESR) and the conduction electron densityN[cm−2] in the ion implanted silicon layers during annealing at 300° to 1000°C are presented.

ISSN:0033-7579    

DOI:10.1080/00337577608234777

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The Monte Carlo technique has been applied to simulate the trajectories of ions implanted into an amorphous target. By this method much information about the spatial distribution of ions is obtained in a straightforward way: the results show a good agreement with the experiments available in current literature.

ISSN:0033-7579    

DOI:10.1080/00337577608234778

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The flux distribution of channeled ions has been calculated for 1 MeV He+in the (100) channel of Cu as a function of the incident angle with the analytical method based on the continuum approximation and the results are compared with those of the Monte Carlo calculations made by Morgan and Van Vliet. General features of the angular dependence of the flux such as the occurrence of the double peak and the incident angles at the maxima agree well in both calculations except for positions along the side of the channel. The scattering yields have been also calculated for atoms located at various positions in the channel. The obtained half-angle of the channeling dip shows a similar temperature dependence as that by Barrett, but the value is larger by 10%. The calculated minimum yield is smaller by a factor of three than that by Barrett. In order to see the discrepancy, the effectiveness factor is calculated on the basis of the continuum approximation and it is found that the effectiveness factor for atoms at the string at the transverse energies near the critical value is substantially smaller than that of the Monte Carlo calculations. However, this discrepancy in the effectiveness factor is found to make little contribution to the scattering yield for the atoms located inside the channel.

ISSN:0033-7579    

DOI:10.1080/00337577608234779

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

ISSN:0033-7579    

DOI:10.1080/00337577608234780

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

ISSN:0033-7579    

DOI:10.1080/00337577608234781

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

ISSN:0033-7579    

DOI:10.1080/00337577608234782

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor