Temperature Dependence of Defects in Hydrogen-Implanted Silicon Characterized by Positron and Ion-Beam Analyses

Nanometer-sized voids formed in Si after H implantation to a dose of 3¥1016 cm-2 and annealing at 600 or 800 ¡C were characterized by slow-positron and ion-beam analyses. Depth profiles of defects were calculated from the S parameter curves of Doppler broadening and from Rutherford backscattering/channeling spectra. Concentrations of gettering sites were also calculated from the Rutherford backscattering spectra of the samples after Au gettering. Defect profiles by Doppler broadening measurements were found to be shallower than the projected range of implanted H, while profiles of defects and gettering sites detected by the backscattering measurements were close to the projected range. The peak concentrations of defects and gettering-sites were dependent on annealing temperature and analytical techniques. The observed annealing behaviors can be explained by the evolution of vacancy clusters and the interaction of H with defects.