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The Finite-Difference Time-Domain (FDTD) numerical simulation method has been applied to interpret cathodoluminecence patterns observed for ZnO nanorods grown by a hydrothermal method. The 3D FDTD simulation reproduced the radial electromagnetic field pattern in the hexagonal resonator, corresponding to the CL emission maps of real ZnO microrods. The simulation result for the H z (TE) polarization—the intense field distribution along edges of the structure, in particular in the corners, but weak in the centre—matched the CL pattern particularly well. Since the experiment was not polarization sensitive, we suppose that polarisation sensitive transmission of electromagnetic field through the ZnO/air interface leads to such an observation. The results of the simulation show also that the lack of axial Fabry-Pérot-like resonances in the CL experiments is caused by leaking of the electromagnetic field from the ZnO resonator into the GaN substrate.

In this work the ZnO:Al films of different thickness are grown on the Porous Anodic Alumina (PAA) and p-Si (100) substrates by Atomic Layer Deposition. The ZnO:Al films thicknesses are chosen appropriately in order to obtain complete filled pores as well as pores with a thin covering on the surface. The obtained structures are investigated with spectroscopic ellipsometry and Scanning Electron Microscopy (SEM) techniques.

We present the nanocomposite carbonaceous-palladium (C-Pd) thin films prepared by physical vapor deposition (PVD) and chemical vapor deposition (CVD) methods. Scanning electron microscope (SEM) and transmission electron microscope (TEM) methods were used to study the topography, morphology and structure of carbon and palladium nanograins contained in these films. The quantitative analysis of the elemental composition of C-Pd films was determined by energy-dispersive spectroscopy (EDS). The initial PVD films were modified in a CVD quartz reactor using xylene (the mixture of isomers) as a modifying factor at different times (5, 10 and 30 minutes) at a constant temperature of 650°C in atmospheric pressure. It was observed that the average size of palladium nanograins increased with an increasing duration of modification process. The differences in microstructures observed in the CVD films modified at different times, affect their response in measurements of resistance changes in the gas containing H2 in various concentrations. All samples were measured by cathodoluminescence (CL) method. In CL studies a large amount of objects with high intensity of CL was found. Some of them show the emission bands both at 450 nm and 750 nm. Other reveals emission band only at 450 nm. CL observations show that Pd nanograins coated by graphite shells exhibit optical activity.

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

This work reports on the zinc oxide layers grown by atomic layer deposition (ALD) from dimethylzinc (Zn(CH3)2, DMZn) or diethylzinc (Zn(C2H5)2, DEZn) and deionized water precursors. These films are suitable for nanoelectronic applications, e.g. selecting elements in the new generation of non-volatile 3D memories constructed in the cross-bar architecture. This architecture imposes strict requirements on the parameters of obtained ZnO layers. Growth temperature must be below 200 °C, electron concentration not higher than 1017 cm−3 and mobility above 10 cm2 V−1 s−1. This is possible when the ALD growth method is used. We demonstrate the correlations between the structural, optical and electrical properties of ALD-ZnO layers. Their control allows us to obtain Schottky junctions with silver, whose parameters are suitable for the applications mentioned above. The ideality factor of about η ≈ 2.65 was calculated for the Schottky diodes based on the pure thermionic emission theory.