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Abstract: In this work, an alternative approach for CIGS thin film growth has been tested, which is different from the common co-evaporation process. Such approach consists of sputtering deposition of the metal elements combined with selenium evaporation. This new and easily scalable procedure allows deposition time of the CIGS layer lower than 15minutes and can be easily applied not only on rigid but also on flexible substrates in a roll to roll configuration, matching industrial application requirements. The relationships between the growth parameters of such hybrid sputtering/evaporation method and the chemical-physical properties of the CIGS films and cells have been studied. [Copyright &y& Elsevier]

The 16p13.3p13.1 region has been reported as a “critical” hotspot region for recurrent microdeletions/duplications, which may contribute to epilepsy, learning difficulties and facial dysmorphisms. Cytogenetic and array-CGH analyses were performed because of the clinical characteristics of the patient. The girl showed de novo 16p13.3p13.13 duplication spanning a region of ∼5.3 Mb. She presented brain anomalies, intellectual disability, epilepsy, facial and vertebral dysmorphisms. To our knowledge, this is the first reported case of 16p13.3p13.13 duplication; only three patients with an overlapping deletion in 16p13.2p13.13 were previously described. The duplicated region contains 21 OMIM genes and, six of them ( RBFOX1 , TMEM114 , ABAT , PMM2 , GRIN2A and, LITAF ) were found to be associated with known diseases. Although no duplication of these genes has been described in the literature, we discuss here if they had some role in determining phenotype of our patient. [ABSTRACT FROM AUTHOR]

Abstract: The potentials of using silicon–germanium dots as stressor material in MOSFETs are evaluated with respect to integration in today’s production processes. Work is reviewed that has lead to the fabrication of the first experimental n-channel MOSFETs on SiGe dots, referred to as DotFETs, in a low-complexity, custom-made low-temperature process where the dot is preserved during the entire device processing. The SiGe dots were grown in large regular arrays in a Stranski–Krastanow (S–K) mode and used to induce biaxial tensile strain in a silicon capping-layer. The DotFETs are processed with the main gate-segment above the strained Si layer on a single dot. To prevent intermixing of the Si/SiGe/Si structure, the processing temperature is kept below 400°C by using excimer-laser annealing to activate the source/drain implants that are self-aligned to a metal gate. The crystallinity of the structure is preserved throughout the processing and, compared to reference devices, an average increase in drain current up to 22.5% is obtained. The experimental results are substantiated by extensive simulations and modeling of the strain levels in capped dots and the corresponding mobility enhancement achievable with DotFETs. The concept of SiGe dots overgrown with a Si layer is also considered for use as a starting structure for silicon-on-nothing (SON) technology where the dot should be removed after the formation of the gate-stack and the strain for mobility enhancement should be preserved (and possibly increased) via the other device layers. [Copyright &y& Elsevier]

Abstract: Silicon-rich SiGe alloys represent a promising platform for the development of large-area single-mode optical waveguides to be integrated in silicon-based optical circuits. We find that SiGe layers epitaxially grown on Si successfully guide radiation with a 1.55μm wavelength, but, beyond a critical core thickness, their optical properties are strongly affected by the clustering of misfit dislocations at the interface between Si and SiGe, leading to a significant perturbation of the local refractive index. Transmission electron microscopy and micro-Raman spectroscopy, together with finite-element simulations, provide a complete analysis of the impact of dislocations on optical propagation. [Copyright &y& Elsevier]

This review emphasizes progress in theoretical simulation and experiments that have been performed in the past years for semiconducting silicides. New fundamental electronic and optical properties of Ca2Si and BaSi2, recently found RuSi2 phase, ternaries in Fe–Os–Si and Ru–Os–Si systems, β-FeSi2, Mg2Si and CrSi2 with stretched and compressed lattices as well as transport properties of β-FeSi2, ReSi1.75, Ru2Si3 are presented. Prospects for practical applications of semiconducting silicides are discussed. [Copyright &y& Elsevier]

[Display omitted] • We report on the design of a suitable compliant substrate, based on Si micropillars, to grow (1 1 1) 3C-SiC films. • The new T-shape design of the pillars further improves the strain relaxation, preventing wafer bowing. • Growth of thick (1 1 1) 3C-SiC films allowed for the first time to study the defects evolution along the [1 1 1] direction. • Our model estimates that a stacking fault density below 5 × 102 cm−1 could be achieved in 300 μm-thick films. • We observe and explain the origin of the grain boundary closure in 3C-SiC films grown along the [1 1 1] direction. In this paper we report the morphology and the microstructural properties of thick [1 1 1]-oriented 3C-SiC films epitaxially grown on T-shaped Si micropillars. This compliant substrate was designed to release the stress developed in 3C-SiC grown on Si, due to the lattice mismatch and the different thermal expansion coefficients between 3C-SiC and Si. In this way it was possible to have 3C-SiC films as thick as 10 and 16 μm, with small bowing and no cracks. Our study relies on the use of an Electron Microscopy approach and elucidates the structure of the crystallographic defects across the 3C-SiC film, such as stacking faults (SFs), nano-twins and grain boundaries (GBs). After examination of the morphological and structural characteristics of the Si micropillar array, we analyzed the crystallographic properties of the thin 3C-SiC deposit on the Si micropillar sidewalls, since it may have an impact on the upper film. To assess the crystal quality of the 3C-SiC film, we quantified the SF density at the 3C-SiC surface, even estimating semi-quantitatively the depletion of SFs at much larger thickness. Hence, we analyzed the regions where 3C-SiC microcrystals grown on neighboring Si micropillars coalesce and form a continuous layer. We found that the coalescence between adjacent 3C-SiC microcrystals produces twinned regions, which terminate with the formation of GBs. We noticed that SFs may annihilate at the GBs, leading to the SF reduction across the 3C-SiC film. Finally, we observed the closure of the GBs inside the 3C-SiC film, thus improving the crystal quality of its surface. This work endorses the use of Si micropillars as compliant substrate to grow thick [1 1 1]-oriented 3C-SiC films with good crystal quality and is preliminary to the exploitation of 3C-SiC for high performing microelectronic devices. [ABSTRACT FROM AUTHOR]