Study of radiation damage restoration and antimony ions redistribution in Si(100) and Si(111) crystals

摘要

In this work, we study the radiation damage restoration and antimony ions redistribution into and oriented silicon substrates. The samples are implanted with antimony to a dose of 5 x 10(14) Sb+ cm(-2) at 60 keV energy, then annealed under oxygen atmosphere at 900degreesC, 30 min. The thin layer of SiO2 (which is formed on Si surface by dry oxidation and expected to prevent any loss of Sb+ dopant during Si recovery) is removed by a 10 HF solution. The specimens are analyzed by H+ Rutherford Backscattering Spectrometry (RBS) operating at 0.3 MeV energy in both random and channelling modes. The values of the projected range, R-p, the standard deviation, DeltaR(p), and the dose of antimony ions, which are estimated with a simple program, are in agreement with tabulated ones. It is also shown that the surface damage restoration is better for Si(1 0 0) samples than for Si(1 1 1) ones, in other words, the radiation damage is more significant in Si(1 1 1) substrates. Moreover, for both Si(1 0 0) and Si(1 1 1), it has been noticed that an important quantity of implanted antimony is localized in substitutional silicon sites. This fact is more pronounced in Si(1 0 0). On the other hand, it has been found, for Si(1 0 0) substrates only, that antimony ions are redistributed into the silicon lattice following a Gaussian law. (C) 2001 Elsevier Science B.V. All rights reserved. References: 11