Radiation‐induced structural transformations in a silicon layer of SOI

Abstract

AbstractThe differences in the secondary processes proceeding in the silicon layer of SOI and reference bulk silicon wafers are revealed by using High‐Resolution X‐ray diffraction and Rutherford Backscattering spectroscopy methods. The damage depth profiles in the implanted layers described by both strain and static Debye–Waller factor profiles, were reconstructed from the diffraction patterns using an autofitting procedure, based on a genetic algorithm. The contribution of diffuse scattering was excluded using the triple‐crystal diffractometry technique. The defect density profiles were obtained from the RBS/Channelling measurements, which were carried out using 4He+ beam at 2.0 MeV. The DICADA code, based on the theoretical description of dechanneling was used to interpret the RBS/C data. Accumulation kinetics, spatial distribution, and concentration of radiation‐induced defects in the topmost silicon layer of SOI and a bulk silicon were shown to be essentially different. The influence of the fields was shown to lead to the loss of crystallinity of the thin surface layer of silicon in SOI due to accumulation of vacancy‐type defects and increase of concentration of interstitial atoms near the internal interphase boundary “Si–SiO2”. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)