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This paper reports on the electrical and optical properties of zinc oxide thin films grown at the temperature range between 160 and 240 °C by the atomic layer deposition method using diethylzinc (Zn(C 2 H 5 ) 2 , DEZn) and deionized water precursors. Silicon and glass were used as substrates for the ZnO growth. These films were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), low temperature photoluminescence (LT PL) and low temperature Hall effect measurements. This analysis revealed that all the obtained as-grown ZnO layers are fairly smooth (with a roughness RMS parameter less than 4 nm), show a metallic-like conductivity, exhibited a carriers' concentration (n) of 10 19 -10 20 cm -3 which was found to be practically independent of temperature between 7 and 300 K. From the LT PL spectra, it was established that the carriers' concentration is nearly inversely proportional to the intensity of the LT PL edge emission peak. These observations, together with the fact that the Hall mobility slightly increases at higher temperatures, indicate the existence of a competitive scattering mechanism (on grain boundaries as well as on ionized impurities). However, ionized impurity scattering seems to be the dominant factor limiting the carrier mobility in the discussed case. Moreover, the results suggest that efficient non-radiative Auger processes are responsible for the observed photoluminescence (PL) quenching in the samples with higher electron concentration.

Zinc oxide crystals were grown by CVT contactless technique and thermally annealed in the air, nitrogen or oxygen atmospheres, or zinc or arsenic vapours. Wide ranges of annealing times and temperatures were applied. The variety of morphology and quality of the crystal surface was investigated by AFM and XRD. It was found, that thermal annealing in the air, nitrogen, oxygen and zinc resulted in similar evolution of the crystal surface, although there are observed differences in the rate of the changes. The annealing in zinc vapour resulted in roughness (RMS) lower than 1 nm. The annealing in arsenic vapour leads to degradation of the crystal surface. The improvement of the surface was not observed in case of thermal annealing of the rough ZnO surfaces obtained by ALE homoepitaxy on the smooth CVT as-grown ZnO surfaces.

The new trend in semiconductor technology is search of new materials, which could replace silicon in specialized applications. One of them is zinc oxide (ZnO), a II-VI semiconductor. In this work we show how to obtain at relatively low temperature monocrystalline layers of ZnO using atomic layer deposition (ALD) method with reactive dimethylzinc (DMZn) and diethylzinc (DEZn) precursors. ZnO films were deposited on gallium nitride substrates at 300°C. We compare the results obtained for these two organic zinc precursors. High resolution X-ray diffraction analysis proves that our ZnO layers are monocrystalline with FWHM of (00.2) peak 250 arcsec for DEZn and 335 arcsec for DMZn precursors.