The structural, optical, and electrical properties of zinc oxide (ZnO) layers manufactured at different process conditions were investigated. ZnO epitaxial layers were grown on silicon, glass, and ITO/glass substrates by pulsed laser deposition (PLD) technique. The influence of power beam, substrate temperature, and deposition time on films properties was analysed. Morphological features of the film surface were investigated by scanning electron microscopy. A structural study shown planar orientation of films at low temperatures of substrate, but the columnar type of growth originated in temperature enhances. Electrical properties were determined in the temperature range 300–500 K. It was shown that the type of films conductivity is metallic and it is limited by charge transfer across grain boundaries.

Copper oxide-titanium dioxide (TiO₂) p–n junctions are promising materials for photovoltaic devices and may reduce production costs due to their low cost and inexpensive production methods compared with silicon solar cells. The present review compares solar cells made with copper oxides combined with TiO₂–TiO₂/Cu₂O and TiO₂/CuO heterojunctions, and “cascade heterojunction systems.” First, we describe the main properties of titanium (iv) dioxide (TiO₂), cuprous oxide (Cu₂O), and cupric oxide (CuO), and their potential applications. Next, we explain the concept of copper oxide and TiO₂ heterojunctions. We summarize and present the photovoltaic characteristics (efficiency, fill factor, circuit current density, and open circuit voltage), thickness, preparation method, and electrode type for solar cells comprising copper oxide and TiO₂. The efficiency of the solar cells ranged from 0.0005% to 1.62%. The thickness of the TiO₂ and cupric oxide layers ranged from 0.06 to 16 µm, and from 0.18 to 1.5 µm, respectively, depending on the fabrication method. Additionally, we review and discuss the available combinations of copper oxide with other materials (Cu₂O with ZnO, CuO with ZnO, and CuO with Si), as well as the effect of the thickness of the copper (i) oxide and copper (ii) oxide on the solar cell performance. Finally, we present aspects to improve the conversion efficiency of heterojunction solar cells with copper oxides combined with TiO₂. This review will be useful for the construction and further development of thin-film solar cells.

We obtained zinc oxide films doped with aluminum using atomic layer deposition (ALD). Their morphology, growth mode, optical and electrical properties are studied. Al content dependence is analyzed. Carrier scattering mechanisms in ZnO:Al (AZO) films are investigated from conductivity versus temperature measurements. We also discuss how the film thickness affects its resistivity and optical transmission. The obtained film resistivities, i.e. 7 × 10⁻⁴ Ωcm, belong to the lowest reported so far for transparent ZnO:Al films grown by the ALD method.