ISSN:0033-7579    

DOI:10.1080/00337577808233180

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The transport of fast particles in a heterogeneous substrate is studied using the path length approximation. With the power law scattering model, exact solutions are obtained for the energy deposition rate and the implanted ion density in two contiguous, but dissimilar, plane layers. A discontinuity in the particle density at the interface is observed which is consistent with the Monte Carlo resultsofFurukawa and Ishiwara and with some recent work of Winterbon. The method shows promise of predicting implanted ion distributions with some confidence.

ISSN:0033-7579    

DOI:10.1080/00337577808233181

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A three-stage model to explain how the secondary defects consisting of interstitial dislocation loops evolve from the primary defects in ion-implanted silicon is presented. Crystals implanted to an ion dose belowDc(critical dose which forms a continuously damaged layer), such that the primary damage clusters do not overlap, were studied. The model suggests that the Frenkel pairs formed by ion impact produce submicroscopic clusters of vacancies and interstitials which are stable up to about 900 K. Upon heating to a higher temperature the smallest interstitial clusters emit mobile interstitials and/or the vacancy clusters emit mobile vacancies. The larger clusters grow and convert to dislocation loops. Vacancy loops shrink and disappear; interstitial loops grow because of the excess of interstitial'. The total area per unit area of interstitial loops remaining after a high temperature anneal above 1100 K corresponds to the number per unit area of the implanted atoms. The implication of this is that for vacuum and dry nitrogen anneals the surface is not important as a sink or source for point defects and that the annealing processes occur almost entirely within the buried damaged region.

ISSN:0033-7579    

DOI:10.1080/00337577808233182

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Des échantillons d'alliage Ni2Cr ordonné à longue distance ou à courte distance (état K) ont été iradiés aux neutrons à la température de l'hydrogene liquide. Les variations de résistitivé au cours de l'irradiation mettent en évidence un comportement différent suivant l'état structural initial: accroissement de résistivité pour l'échantillon ordonné a longue distance et décroissance de résistitivé pour l'éichantillon présentant l'itat K. Ce dernier phénoméne peut-ětre dû à la superposition d'un effet lié à la production des défauts ponctuels et d'un effet lié à la destruction de l'ordre à courte distance. L'étude de la restauration isochrone aprés irradiation montre l'existence dans tous les cas de trois stades principaux qu'on peut interpréter selon le schéma général des métaux purs, c'est-àdire d'abord recombinaison des paires proches puis migration et élimination à plus grande distance des interstitiels et enfin migration et élimination des lacunes.

ISSN:0033-7579    

DOI:10.1080/00337577808233183

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The effect of irradiation with thermal neutrons at low and high dose levels on TSC and PLS of “pure” and Ag-doped CdS single crystals has been investigated. Following the small dose of irradiation (1015n/cm2) two low temperature peaks of TSC at 51 K and 78 K increased or appeared as a result of (n, γ) reaction on114Cd. We supposed their connection with intrinsic defects of CdS. The experiment with high energy (220 keV) electron irradiation helped us to identify these peaks with Cd1and V5respectively. At a high dose level of irradiation (1018n/cm2) a new peak of TSC spectra is produced. It is related withInformed by transmutation of115Cd. Two bands in PLS are dominant after irradiation: R-band (λmax. = 0.73 μm) and IRco-band (λmax= 1.04 μ). Their peculiarity is the temperature quenching with activation energy (0.2 ± 0.03) eV and (0.05 ± 0.02) eV respectively. Models of this radiative transition and nature of DA pairs responsible for them are speculated.

ISSN:0033-7579    

DOI:10.1080/00337577808233184

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Results are presented of an investigation of the residual defect structure after high-temperature (>1000°C) annealing (HTA) of implanted layers in silicon. The most typical defects after HTA are dislocation loops (DL) and a misfit dislocation network (MDN). The effect of the irradiation and annealing conditions on the defect formation are presented. The important role of point defects in MDN formation is discovered. A possible role of these defects in changing electrophysical properties of the implanted layers is discussed.

ISSN:0033-7579    

DOI:10.1080/00337577808233185

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Mechanisms of the crystalline-to-amorphous transition on ion implantation, the homogeneity of the amorphous layer, the thermal and radiation-structural rearrangements of the ion-implanted layers have been considered. The main results have been obtained by esr and reflection electron diffraction techniques.

ISSN:0033-7579    

DOI:10.1080/00337577808233186

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Ion-implanted impurity profiles were studied after laser annealing in different regimes. It was found that the redistribution of impurities in silicon occurs after annealing with both millisecond and nanosecond laser pulses. The character of redistribution depends on the power density of the light beam. In the case of relatively low power-density the most probable mechanism of impurity migration seems to be interstitial diffusion. For high power-densities the redistribution is caused by the flux of excess vacancies or by the recrystallization of the melted surface layer.

ISSN:0033-7579    

DOI:10.1080/00337577808233187

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The stoichiometry of compound semiconductors interacts with the solubility of impurities. Oxygen impurity in ZnTe is a good element for solubility studies because oxygen doped ZnTe exhibits a well characterized luminescence spectrum. It is shown that Zinc implantation in nominally undoped ZnTe brings out an oxygen-related luminescence spectrum, revealing some previously inactive oxygen impurities.

ISSN:0033-7579    

DOI:10.1080/00337577808233188

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

In situelectron irradiation damage has been produced in foils of magnesium of two purities (99.995% and 99.9%) in the 200 kV electron microscope. The concentration of the electron beam-induced point defect clusters in the form- of dislocation loops in the 99.9% magnesium was a factor of ten higher than that in the 99.995% material, indicating that loop nucleation and/or growth were sensitive to specimen purity. The growth kinetics of most of the dislocation loops indicated that the surfaces of the thin foils acted as dominant sinks for the electron-produced point defects. The nature of dislocation loops previously induced in magnesium by neutron irradiation was determined from their behavior under subsequent electron irradiation.

ISSN:0033-7579    

DOI:10.1080/00337577808233189

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor