CuO/ZnO nanocomposites were synthesized on Al(2)O(3) substrates by a hybrid plasma-assisted approach, combining the initial growth of ZnO columnar arrays by plasma-enhanced chemical vapor deposition (PE-CVD) and subsequent radio frequency (RF) sputtering of copper, followed by final annealing in air. Chemical, morphological, and structural analyses revealed the formation of high-purity nanosystems, characterized by a controllable dispersion of CuO particles into ZnO matrices. The high surface-to-volume ratio of the obtained materials, along with intimate CuO/ZnO intermixing, resulted in the efficient detection of various oxidizing and reducing gases (such as O(3), CH(3)CH(2)OH, and H(2)). The obtained data are critically discussed and interrelated with the chemical and physical properties of the nanocomposites.

The application of new zirconium precursors for the fabrication of ZrO2 and ZrN thin films by metalorganic chemical vapor deposition (MOCVD) is presented. The all-nitrogen coordinated Zr precursors exhibit improved thermal properties for vapor phase fabrication of thin films. The growth of ZrO2 thin films was realized by the combination of the Zr complex with oxygen, while the formation of ZrN thin films was achieved for the first time employing a single source precursor (SSP) approach. This was enabled by the presence of nitrogen containing ligands which contributes to the formation of the ZrN phase without the need for any additional nitrogen source in contrast to classical film growth processes for ZrN thin films. In the first step the newly developed precursors were evaluated thoroughly for their use in MOCVD applications, and in the next step they were utilized for the growth of ZrO2 and ZrN thin films on Si(100) substrates. Polycrystalline ZrO2 films that crystallized in the monoclinic phase and the fcc-ZrN films oriented in the (200) direction were obtained, and their structure, morphology, and composition were analyzed by a series of techniques. This work shows the potential of tuning precursors for vapor phase fabrication of Zr containing thin films with a goal of obtaining two different classes of material systems (ZrO2 and ZrN) using one common precursor.

Zr(NEtMe) 2 (guan-NEtMe 2 ) 2 ], a recently developed compound, was investigated as a novel precursor for the atomic layer deposition (ALD) of ZrO 2 . With water as the oxygen source, the growth rate remained constant over a wide temperature range, whereas with ozone the growth rate increased steadily with deposition temperature. Both ALD processes were successfully developed: the characteristic self-limiting ALD growth mode was confirmed at 300 °C. The growth rates were exceptionally high, 0.9 and 1.15 Å/cycle with water and ozone, respectively. X-ray diffraction (XRD) indicated that the films were deposited in the high-permittivity cubic phase, even when grown at temperatures as low as 250 °C. Compositional analysis performed by means of X-ray photoelectron spectroscopy (XPS) demonstrated low carbon and nitrogen contamination (<2 at. % when deposited with ozone). The films presented low root-mean-square (rms) roughness, below 5% of the film thickness, as well as excellent step coverage and conformality on 30:1 aspect ratio trench structures. Dielectric characterization was performed on ZrO 2 metal−insulator−metal (MIM) capacitors and demonstrated high permittivity and low leakage current, as well as good stability of the capacitance. The ALD reaction mechanism was studied in situ: adsorption of the precursor through reaction of the two guan-NEtMe 2 ligands with the surface −OD groups was confirmed by the quartz crystal microbalance (QCM) and quadrupole mass spectrometric (QMS) results.

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A new heteroleptic titanium precursor with a mixed oxygen/nitrogen coordination sphere [Ti(dmap)2(NMe2)2] (Hdmap = 1–dimethylamino–2–propanol) is synthesized by a simple elimination reaction on tetrakis–dimethylaminotitanium(IV) [Ti(NMe2)4]. The compound shows encouraging results in terms of chemical and thermal stability compared to the parent alkyl amide [Ti(NMe2)4], and is therefore more suitable for MOCVD applications. TiO2 thin films are grown on Si(100) and ITO‐coated borosilicate glass substrates via MOCVD in the temperature range 500–800°C. The deposition temperature has a significant effect on the phase and microstructure of the TiO2 films obtained, which influences the functional properties. The optical bandgaps of the films are in the range 2.92–3.36 eV. The best photocurrent response (1.5 mA cm−2 under AM 1.5G conditions) in aqueous electrolytes is observed for films grown at 700°C having improved crystallinity and porous columnar structure.