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This paper deals with the influence of plural and multiple scattering of high energy projectiles in two applications; Rutherford backscattering spectroscopy (RBS) and the response of particle implanted and passivated silicon detectors (PIPS) to monoenergetic MeV alpha particles. In Rutherford backscattering spectroscopy, multiple scattering leads to a spread in the path length and in the scattering angle of the projectiles. Thus the low energy edge of the RBS spectrum may shift noticeably; the energy transferred to the recoil atoms, and the effective scattering cross-section, are not defined precisely. Due to plural scattering excessive projectile path lengths in the target may occur, producing the low energy background, which extends within the RBS peak. Where the scattering probability is high, projectiles are detectable above the expected high energy edge. In high resolution alpha spectroscopy, energy resolutions smaller than 8 keV were obtained with state of the art PIPS detectors. The spectra showed an asymmetry in the line shape which could be attributed to the asymmetric statistical distribution of energy spent on electronic excitation and ionisation in the sensitive volume of the detector. The detector response to 3183 keV alpha particles was calculated using a detector model which assumed a dead layer near the front contact followed by a fully sensitive volume. The calculated alpha spectrum agrees perfectly with the measurement both in the resolution (FWHM) and in the asymmetric shape.

Additional information

Authors: STEINBAUER E, Universität Linz, Institut für Experimentalphysik (AT);BAUER P, Universität Linz, Institut für Experimentalphysik (AT);BIERSACK J P, Hahn-Meitner-Institut Berlin (DE);BORTELS G, JRC Geel (BE)
Bibliographic Reference: Paper presented: Computer Simulations of Radiation Effects in Solids, Berlin (DE), August 23-28, 1992
Availability: Available from (1) as Paper EN 37132 ORA
Record Number: 199211117 / Last updated on: 1994-11-29
Original language: en
Available languages: en