High-resolution X-ray diffraction of silicon-on-nothing

High-resolution multi-crystal X-ray diffraction was employed to characterize silicon-on-nothing samples consisting of a one-dimensional periodic array of buried empty channels. p- and n-type silicon starting wafers were used for sample preparation. For the p- type samples, this periodic array gives rise to well defined Fraunhofer diffraction when the channels are normal to the scattering plane. This indicates good lattice quality of the layer containing the channels. Moreover, the lattices of the surface layer and the layer with the channels were almost indistinguishable from that of perfect silicon. Conversely, the n-type samples showed such lattice tilts and out-of-plane mosaic spreads in the surface and buried layers that Fraunhofer diffraction does not occur from the periodic array of the channels. The elucidation of this different behaviour is in progress and will most likely be fruitful after X-ray images of the same samples are taken

Crystallization kinetics of boron- and germanium-implanted \u3008100\u3009 Si: a balance between doping and strain effects

Electrical and strain arguments were used to explain the differences in growth rate observed for silicon solid phase epitaxy in the presence of electrically active dopants and neutral impurities. In the case of dopants, strain effects seem to be absent or at least to play a negligible role, while for neutral impurities strain seems to be very important. The purpose of this work was to study the role of dopants in the presence of intentionally strained silicon films. The studies were performed by comparing the growth rates measured in samples implanted with boron and germanium, and the growth rates obtained in samples implanted with only germanium or only boron. With respect to intrinsic silicon, boron produces a rate enhancement, germanium a decrease and boron-germanium a slight increase. The results are interpreted by taking into account the strain and by assuming that strain and electrical effects are independent

X-ray diffraction study on proton-irradiated high-purity aluminum

Double-crystal X-ray diffractometric technique was applied to the study of defects formed in proton-irradiated Al single crystal. The results are consistent with the formation of interstitial dislocation loops; their density and average size are evaluated on the basis of the Krivoglaz treatment and compared with theoretical estimates. © 1989

Dependence of Anomalous Phosphorus Diffusion in Silicon on Depth Position of Defects Created by Ion Implantation

Transient enhanced diffusion of phosphorus in silicon has been investigated for implants below and above the threshold for a complete amorphization. Rapid thermal processes (electron beam) and conventional furnaces have been used for the annealing. In the case of implants below amorphization, a strong enhanced diffusion, proportional to the amount of damage produced, has been observed. The extent of the phenomenon is practically independent of the damage depth position. In contrast to this, the formation of extended defects at the original amorphous-crystalline interface makes the diffusivity strongly dependent on depth in the case of post-amorphized samples. No enhanced diffusion effect is observed if the dopant is confined in the amorphous layer, while a remarkable increase in the diffusivity is detected for the dopant located in the crystalline region beyond the amorphous-crystalline interface