Role of cross-slipping in formation of edge dislocations in heteroepitaxial systems GeSi-on-Si(001) and Ge-on-InGaAs/GaAs

Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate.     

Shuffle-set dislocation nucleation in semiconductor silicon device

We have found that a shuffle-set dislocation is nucleated in a semiconductor silicon device subjected to severe thermal processing. The dislocation transforms into a dissociated glide-set dislocation after annealing at 500°C. A possible mechanism for the nucleation of a perfect shuffle-set dislocation during thermal processing is that the dislocation nucleus was nucleated at a low temperature during prior ion-implantation processing.     

Effects of irradiation with electrons of different energies on the dark conductivity and the network of hydrogenated amorphous silicon films

The effects of irradiation with electrons having energies in the range 0.7–1.7 MeV on the dark conductivity and the network of hydrogenated amorphous silicon (a-Si:H) thin films have been studied. The dark conductivity measurements show that electron irradiation leads to a degradation in the dark conductivity, with the degradation being greater at lower electron energies. The Raman results suggest that the irradiation induces structural defects in the a-Si:H films, with the lower energy electrons producing more disorder in the amorphous network.     

Observation of phase separation in magnetron sputter-deposited Al–Cu thin films

The microstructures of Al–1.8 to 92.5?at.% Cu thin films prepared by radiofrequency (13.56?MHz) cathodic magnetron sputtering have been investigated by X-ray diffraction (XRD) and transmission electronic microscopy (TEM). A phase separation occurs in films of nominal Al–66.64?at.% Cu composition, consisting of a fcc Al solid solution phase, a fcc Cu solid solution phase and an unexpected sc Cu₃Al ordered phase with a Cu₃Au structure and a lattice parameter of about 0.36?nm.     

Octapod-shaped,nanosized, amorphous precipitates in a crystalline ferrite matrix

The development of uniquely octapod-shaped nanosized amorphous silicon–nitride precipitates in a ferrite matrix was observed upon nitriding of Fe–4.5at.%Si alloy. The legs of the amorphous precipitate are oriented along ?1?1?1?-directions of the ferrite. The occurrence of such peculiarly shaped amorphous silicon–nitride precipitates, which experience a volume misfit of more than 100% with the surrounding ferrite, was attributed to precipitate growth influenced by long-range diffusion within the evolving highly anisotropic stress field around the developing precipitates after nucleation.     

Long-term metastability of light-induced defects in hydrogenated amorphous silicon

The decay of the peak intensity of the electron spin resonance signal associated with light-induced dangling bonds in a-Si(H) has been measured at room temperature as a function of time during very long intervals such as 3400 days after the intense pulsed illumination was turned off. The decay curve is fitted by an exponential function with a decay constant of 393 days and reaches a steady-state value smaller than the value taken before illumination. Such a long-term metastability of light-induced dangling bonds in a-Si:H is discussed in terms of reconstruction of the amorphous network occurring through hydrogen motion.     

Atomic arrangement at the 3C-SiC/Si(001) interface revealed utilising aberration-corrected transmission electron microscope

The atomistic structure of the 3C-SiC/Si(001) interface has been investigated using a combination of aberration-corrected transmission electron microscopy and a newly developed image processing method for eliminating artificial contrast. The structures having periods four times longer than those of the silicon lattice have been observed distinctly in images taken along both Si[110] and Si[100] directions. Contrary to theoretical models proposed previously, the interface of the three-dimensional structural model that we constructed on the basis of our experiments has a silicon-rich configuration. We have clarified that the strain field induced by the two-dimensional misfit between Si(001)-(4?×?4) and SiC(001)-(5?×?5) is relaxed by the two-dimensional network of misfit dislocations; simple edge dislocations with [100] and [010] directions and Lomer dislocations with [110] and [110] directions. The atomistic structures of the Lomer dislocations have been also clarified.     

Cascade effects on the irradiation stability of amorphous SiOC

We studied the heavy ion radiation tolerance of amorphous silicon oxycarbide (SiOC) alloys by in situ Kr ion irradiation within a transmission electron microscopy. The amorphous SiOC thin films were grown via co-sputtering from SiO₂ and SiC targets on a surface-oxidized Si (100) substrate. These films were irradiated by 1 MeV Kr ions at both room temperature and 300 °C with damage levels up to 5 displacements per atom (dpa). TEM characterization shows no sign of crystallization, void formation or segregation in all irradiated samples. Our findings suggest that SiOC alloys are a class of promising radiation tolerant materials.     

On the Symbiosis of Science and Religion: A Jewish Perspective

Three theses are explored, the first two historical and the third philosophical-theological: (1) throughout most of the history ofWestern civilization, science and religion have been closely connected with each other, and each has benefited from the connection; (2) the belief that science and religion have always been in conflict is not based on the actual history of either set of institutions; and (3) structurally a relationship between the two institutions is in the interest of both. By religion here I mean specifically, but not exclusively, Judaism.