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We demonstrate that room temperature ferromagnetic response (RT FR) of ZnCoO films grown at low temperature by the atomic layer deposition (ALD) method is due to Co metal accumulations at the ZnCoO/substrate interface region. The accumulated experimental evidences allow us to reject several other explanations of this effect in our samples, despite the fact that some of them are likely to be responsible for the low temperature FM in this class of the material.

ZnCoO is one of the most studied and promising semiconductor materials for spintronics applications. In this work we discuss optical and electrical properties of ZnCoO films and nanoparticles grown at low temperature by either Atomic Layer Deposition or by a microwave driven hydrothermal method. We report that doping with Cobalt quenches a visible photoluminescence (PL) of ZnO. We could observe a visible PL of ZnO only for samples with very low Co fractions (up to 1%). Mechanisms of PL quenching in ZnCoO are discussed. We also found that ZnO films remained n-type conductive after doping with Co, indicating that a high electron concentration and Cobalt 2+ charge state can coexist., Comment: 2 pages, 2 Figures, 17 references

We report on the structural, electrical and magnetic properties of ZnCoO thin films grown by Atomic Layer Deposition (ALD) method using reactive organic precursors of zinc and cobalt. As a zinc precursor we applied either dimethylzinc or diethylzinc and cobalt (II) acetyloacetonate as a cobalt precursor. The use of these precursors allowed us the significant reduction of a growth temperature to 300oC and below, which proved to be very important for the growth of uniform films of ZnCoO. Structural, electrical and magnetic properties of the obtained ZnCoO layers will be discussed based on the results of SIMS, SEM, EDS, XRD, AFM, Hall effect and SQUID investigations., 4 pages, 3 figures, 6 references

Optical and magneto-optical properties of ZnCoO films grown at low temperature by Atomic Layer Deposition are discussed. Strong wide band absorption, with onset at about 2.4 eV, is observed in ZnCoO in addition to Co-related intra-shell transitions. This absorption band is related to Co 2+ to 3+ photo-ionization transition. A strong photoluminescence (PL) quenching is observed, which we relate to Co recharging in ZnO lattice. Mechanisms of PL quenching are discussed., Comment: 21 pages, 4 figures, 44 refereces, original paper

ZnCuO thin lms have been deposited on silicon, glass and quartz substrates by atomic layer deposition method, using reactive organic precursors of zinc and copper. As zinc and copper precursors we applied diethylzinc and copper(II) acetyloacetonate. Structural, electrical and optical properties of the obtained ZnCuO layers are discussed based on the results of scanning electron microscopy, energy dispersive spectroscopy, X-ray di raction, atomic force microscopy, the Hall e ect and photoluminescence investigations.

In this paper we report on ZnCoO thin films grown by atomic layer deposition method in reactor F-120 Satellite. ZnCoO films were grown at low temperature (Ts = 160 ◦C) with a new zinc precursor (dimethylzinc — DMZn) and with cobalt (II) acetyloacetonate (Co(acac)2) as a cobalt precursor and deionized water as an oxygen precursor. In this paper we concentrate on the methods of homogenizing Co distribution in ZnCoO films.

Electrical and magnetic properties of ZnCoO thin films grown on silicon substrates by atomic layer deposition method are investigated. The films were grown using reactive organic precursors of zinc and cobalt. The use of these precursors allowed us the significant reduction of a growth temperature to 200 ◦C and below, which proved to be very important for the growth of uniform films of ZnCoO. We have measured the microwave AC conductivity and EPR for two types of ZnCoO samples, with different Co fractions.