A microstructural analysis of silicon-on-insulator samples obtained by high dose oxygen ion implantation was performed by Raman scattering. The samples analyzed were obtained under different conditions thus leading to different concentrations of defects in the top Si layer. The samples were implanted with the surface covered with SiO 2 capping layers of different thicknesses. The spectra measured from the as-implanted samples were fitted to a correlation length model taking into account the possible presence of stress effects in the spectra. This allowed quantification of both disorder effects, which are determined by structural defects, and residual stress in the top Si layer before annealing. These data were correlated to the density of dislocations remaining in the layer after annealing. The analysis performed corroborates the existence of two mechanisms that generate defects in the top Si layer that are related to surface conditions during implantation and the proximity of the top Si/buried oxide layer interface to the surface before annealing. © 1997 American Institute of Physics. ͓S0021-8979͑97͒07120-X͔

Chains, well I can't break away from these chains[… ]And they ain't the kind that you can see.(“Chains,” Gerry Goffin and Carole King)The main aim of this paper is to present a certain notion — that of Coordination — and an associated requirement — the Coordination Requirement (CR) —,and to show how they help us to better understand the communicative role of proper names. A second aim of the paper is to use these notions to defend the kind of view I favour regarding the meaning of proper names — a certain kind of descriptivist theory — by showing that this view is not subject to two seemingly powerful considerations against it that have been provided from two different camps: one from the anti-descriptivist camp (by Saul Kripke in Naming and Necessity), another from the neo-Fregean camp (by Richard Heck in The Sense of Communication). In dealing with these matters, I will have to discuss the role that complex individual concepts (or ideas) play in allowing us to understand and use proper names.

Silicon nanocrystals embedded in amorphous silicon films have been obtained by RF sputtering using two approaches : i) with a pure H2 plasma at different substrate temperatures (between 50° and 250°C) and ii) with the substrate at 250°C, from a mixture of Ar and a variable partial pressure of H2, and annealing at 750°C. In the first case (i) Raman spectra show strong phonon confinement effects and an increase in the crystalline fraction as temperature increases. In the second case (ii), a higher compressive stress is estimated and a close correlation is found between the optical band gap E0 and the hydrogen content in the basic amorphous layer a-Si:H (i.e. before annealing). These results correlate with the TEM data, which corroborate an enhancement of the crystallinity of the layers and an increase in the particle size when the substrate temperature increases. Furthermore, the crystalline fraction remains nearly constant with the H2 partial pressure. The role of hydrogen and voids in the structure of the films is presented and discussed.

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