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Abstract: Hydrogenated nanocrystalline silicon (nc-Si:H) is a very promising material for photovoltaic applications. Notwithstanding its wide application as instrinsic layer in solar cells, many issues regarding its electronic and optical properties are not completely understood. The influence of crystal defects and impurities on the physical properties of nc-Si:H is not completely explored yet. The present contribution aims to report on defective states associated with crystal defects and impurities in nc-Si:H films grown by low-energy plasma enhanced chemical vapor deposition (LEPECVD) technique. Electronic levels associated to defect states were investigated by surface photovoltage spectroscopy (SPS) and the role of defects and impurities on the conduction mechanisms at a microscopic level were investigated by conductive atomic force microscopy (C-AFM). The results will be compared with structural analyses [Copyright &y& Elsevier]

Abstract: We report on the growth of magnetite films directly on thin layers of organic semiconductors by means of an electron beam ablation method. The deposition was performed at room temperature in a reactive plasma atmosphere. Thin films show ferromagnetic (FM) hysteresis loops and coercive fields of hundreds of Oersted. Micro Raman analysis indicates no presence of spurious phases. The morphology of the magnetite film is strongly influenced by the morphology of the underlayer of the organic semiconductor. These results open the way for the application of magnetite thin films in the field of organic spintronics. [Copyright &y& Elsevier]

Abstract: A study on the self-assembly of regiochemically differentiated methyl substituted quaterthiophenes is presented. Hierarchical self-assembly of 5,4′,3″,5‴-tetramethyl-2,2′:5′,2″:5″,2‴-quaterthiophene molecule, 7 leads to unprecedented fluorescent superstructures on glass and mica surfaces made by reiteration of a peculiar V-shaped recurring motif that extended at least for three generations. [Copyright &y& Elsevier]

Bottom contact FET devices were realized, using vacuum evaporated thin films of unsubstituted quinquethiophene and two modified derivatives deposited at different substrate temperatures. X-ray diffraction (XRD) and atomic force microscopy (AFM) data on thin films deposited in the same conditions are reported and related to the electrical characteristics of the devices. [Copyright &y& Elsevier]