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.

No abstract

Copper oxide-titanium dioxide (TiO 2) 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 TiO 2–TiO 2/Cu 2O and TiO 2/CuO heterojunctions, and “cascade heterojunction systems.” First, we describe the main properties of titanium (iv) dioxide (TiO 2), cuprous oxide (Cu 2O), and cupric oxide (CuO), and their potential applications. Next, we explain the concept of copper oxide and TiO 2 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 TiO 2. The efficiency of the solar cells ranged from 0.0005% to 1.62%. The thickness of the TiO 2 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 (Cu 2O 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 TiO 2. This review will be useful for the construction and further development of thin-film solar cells.

No abstract

No abstract

No abstract

The authors have developed a simple, cheap and reproducible technology for obtaining thin-film heterostructures based on CdTe with a given surface morphology during vacuum deposition, which contributes to their low cost [1, 2]. The critical dimensions (thicknesses) of individual layers of the heterostructure were substantiated, a simulation was performed and a wide range of optical properties was investigated [3]. It is shown that for the deposited CdS / CdTe heterostructure on glass it is possible to obtain an efficiency of 15.8%. Given that thin films are relatively new systems, their study can offer much wider opportunities for technological improvement of photovoltaic energy converters. According to the analysis of modern literature data, the efficiency can be increased by performing deposition on ITO films and introducing nanoparticles of controlled sizes.

No abstract