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Backscattering and ion channeling measurements have been carried out on 〈100〉 silicon wafers implanted with a dose of 3×1016 As+/cm2. These samples have been submitted to laser annealing and then to various thermal annealings in the 350–1000 °C temperature range. Three different crystallographic directions, 〈100〉, 〈110〉, and 〈111〉, have been explored. The deactivated As atom displacement with respect to the lattice sites has occurred already by the first stage of electrical deactivation at 350 °C. The average displacement is constant in the considered temperature range and has been found equal to 0.23±0.06 A making an angle of 23±8° with the [100] direction. By comparing this finding with the local atomic As arrangement, deduced from previously reported extended x‐ray absorption fine structure measurements performed on the same samples, new cluster models are presented. These models consist of As2V and As4V clusters during the very early stage of deactivation, and of several As4V clusters grouped together...

Laser‐annealed and further thermally annealed arsenic implanted silicon specimens have been investigated in a range of doses from 1×1016 to 5×1016 As/cm2, with different experimental techniques: electrical measurements, transmission electron microscopy (TEM), double‐crystal x‐ray diffractometry (DCD), and extended x‐ray absorption fine structure analysis (EXAFS). On the as laser‐annealed samples, in the whole range of doses examined, a lattice contraction of the doped layer has been evidenced by DCD, whereas, on the same specimens, EXAFS measurements have shown the presence of a local expansion around substitutional As atoms. The relationship between strain and carrier concentration has been found to be approximately linear and can be described by the presence of a size and an electronic effect, as recently proposed in the literature. The former effect represents the atomic size contribution, while the latter is the strain induced by the variation of the conduction‐band minima due to the doping. After a s...

The electrical deactivation of Sb atoms highly implanted (2 and 5×1016 ions/cm2) in crystalline silicon is studied by the extended x‐ray absorption fine structure (EXAFS) method. By following the evolution of the local atomic environment around the Sb atoms it is shown that the description of the deactivation process must take into account the existence of vacancy complexes, SbV2, in addition to the usual antimony rhombohedric precipitates. These vacancy complexes are already present after laser annealing in the 5×1016 ions/cm2 case. Co‐implantation with boron delays the precipitation of Sb particles, by forming new complexes, SbBV or SbB2, with a Sb atom surrounded by two sites (B and/or vacancy).

Monocrystalline silicon wafers were implanted with Sb and B ions and the Sb atomic environment was sounded by fluorescence EXAFS. After a thermal annealing it is shown that the Sb atoms form SbV2 vacancy complexes and antimony precipitates. The co-implantation with boron delays the formation of precipitates.

Monocrystalline silicon wafers were implanted with As ions and the As atomic environment was sounded by Total Electron Yield EXAFS and fluorescence EXAFS. It is shown that the As atoms form inactive vacancy complexes at low temperature and precipitates at high temperature. The structure of these complexes and precipitates are also discussed.