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  • Author or Editor: A. Giovagnoli x
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Abstract  

Two important problems are discussed: equations and data used for quantitation on one hand, diffusion under irradiation on another hand. It is suggested that recent semiempirical stopping power data for hydrogen and helium are sufficiently accurate to be used in any good calibration method, while for heavier ions it is preferable to use the “double reaction method”, which avoids the use of stopping power data. The problem of the additivity of the stopping powers in the case of compounds is also discussed and it is shown in a specific case that BRAGG-KLEEMAN's rule is valid. Deep diffusion under irradiation has sometimes been mentioned (e.g. F in Ge, Cu in Si): it can be an important source of errors in trace analysis. The possible deep diffusion of F in Ge has been studied: it is shown that such a diffusion does not occur, while surface contamination problems can lead to erroneous observations.

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Abstract  

InP samples were analyzed by charged particle activation analysis. Proton activation at 12 MeV permits the nondestructive survey of 30 elements. The main impurities are Ti, Fe, Ga and Zn (1015 to 2·1016 at/cm3). Oxygen was analyzed separately by triton activation at 3 MeV; the oxygen concentration is normally less than 1016 at/cm3.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Misdaq, G. Blondiaux, N. Bordes, A. Giovagnoli, M. Valladon, L. Wei, M. Hage Ali, C. Maggiore and J. Debrun

Abstract  

Several examples of improvements or of new developments in the field of charged particle activation analysis applied to the study of semiconductors are described: determination of carbon at the sub-ppb level in GaAs, use of 20 to 30 MeV protons for trace analysis in InP, study of radioactivation with 12 MeV tritons, and use of channeling to study the lattice location of carbon atoms at trace level in GaAlAs.

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