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In this work we demonstrate how technological parameters of PVD/CVD method influence the growth of Ni particles' sizes where carbon nanotubes films are grown. In CVD process we changed the growth temperature while other parameters were kept strictly constant. Carbon nanotubes (CNTs) were grown on carbonaceous-nickel substrates by chemical vapor deposition (CVD) of xylene gas at the temperature range 600?700?C. Ni particles' sizes affect diameters, length and distribution density of carbon nanotubes obtained in different temperatures of CVD processes.

A new technique for studying extended defects and dislocation networks is proposed. The approach, based upon the continuum theory of crystal defects, is employed for digital image processing of high-resolution transmission electron micrographs. The procedure starts with the geometric phase method for extracting the lattice distortion field near dislocation cores. Next, the dislocation core distribution (DCD) is recovered from the lattice distortion field. A so-obtained DCD field takes non-zero values only in disordered regions of the lattice. The accuracy of this method is investigated by mathematical integration of the dislocation field over core regions to find the in-plane components of the Burgers vectors. The proposed method is free of topological problems and can be used to study spatial configurations of complex defects in large crystal areas by using a fully automatic computer program. This approach is applied to investigate a network of misfit dislocations in the interfacial region of a GaAs/ZnTe/CdTe heterostructure.

Despite many efforts the origin of a ferromagnetic (FM) response in ZnMnO and ZnCoO is still not clear. Magnetic investigations of our samples, not discussed here, show that the room temperature FM response is observed only in alloys with a non-uniform Mn or Co distribution. Thus, the control of their distribution is crucial for explanation of contradicted magnetic properties of ZnCoO and ZnMnO reported till now. In the present review we discuss advantages of the Atomic Layer Deposition (ALD) growth method, which enables us to control uniformity of ZnMnO and ZnCoO alloys. Properties of ZnO, ZnMnO and ZnCoO films grown by the ALD are discussed., Comment: 41 pages, 19 figures, 48 references, review paper

ZnTe nanowires were grown by molecular beam epitaxy on GaAs substrates of three different orientations: (100), (110), and (111)B. The catalyst droplets were produced through in situ annealing of a previously deposited Au layer and by forming the eutectic alloy with Ga from the substrate. The influence of substrate orientation and growth parameters on the properties of nanowires was investigated using scanning and transmission electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. The growth process was based on the vapour–liquid–solid mechanism and the contribution of the diffusion-induced effect in this mechanism was confirmed by correlating the length and the diameter of the produced nanowires. The nanowires had diameters ranging from 30 to 70 nm and lengths between 1 and 2 µm. The growth axis of the nanowires was and the nanowires grew along directions of the substrate, independent of the substrate orientation used. The nanowires had stacking faults at the bottom and those grown at optimal conditions possessed perfect cubic structure near the top.