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The paper presents the results of research on the surface topography and electrical properties of ITO thin films deposited by PVD for applications in silicon photovoltaic cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness and optical constants were measured using a spectroscopic ellipsometer. To compare the impact of the preparation process on the properties of layers, deposition was carried out at three different temperatures: 25, 200, and 400°C. As the temperature increased, the surface roughness changed, which correlated with the results of structural tests. The crystallite size increased from 11 to 46 nm. This, in turn, reduced the surface resistance. The electrical properties were measured using a four-point probe method and then the prepared solar cells containing ITO thin films in their structure were examined. By controlling the deposition parameters, the surface resistance of the deposited layer (26 Ohm/2) and the efficiency of the prepared solar cells (18.91%) were optimized. Currently, ITO has the best properties for use in optoelectronics and photovoltaics among the known TCO layers. The magnetron sputtering method is widely used in many industries. Therefore, the authors predict that TCO layers can replace currently used antireflection layers and reduce the number and dimensions of front metal contacts in solar cells. [ABSTRACT FROM AUTHOR]

Magnesium and its alloys are attractive temporary implants due to their biocompatibility and biodegradability. Moreover, Mg has good mechanical and osteoinductive properties. But magnesium and Mg alloys have one significant disadvantage: poor corrosion resistance in a physiological environment. Hence, a deposition of various layers on the surface of Mg alloys seems to be a good idea. The purpose of the article is to analyze the structure and morphology of two MgCa2Zn1 and MgCa2Zn1Gd3 alloys coated by SnO2 ALD (atomic layer deposition) films of various thickness. The studies were performed using scanning electron microscopy (SEM), X-ray fluorescence (XRF), and an X-ray diffractometer. The corrosion activity of the thin films and substrate alloys in a chloride-rich Ringer's solution at 37 °C was also observed. The corrosion tests that include electrochemical, immersion measurements, and electrochemical impedance spectroscopy (EIS) were evaluated. The results indicated that SnO2 had a heterogeneous crystal structure. The surfaces of the thin films were rough with visible pores. The corrosion resistance of SnO2 measured in all corrosion tests was higher for the thicker films. The observations of corrosion products after immersion tests indicated that they were lamellar-shaped and mainly contained Mg, O, Ca, and Cl in a lower concentration. [ABSTRACT FROM AUTHOR]

This article presents the results of a research on the effects and properties of the potassium iodide additive onto the structure of the MEH-PPV polymer material, in its aspect of application in the dye-sensitized solar cell. Changes in MEH-PPV surface morphology were researched through increasing of the potassium iodide content measured by scanning electron microscope. The increased content of potassium iodide also led to increased electrical conductivity measured by the Keithley meter. The electrical properties of the dye-sensitized solar cell were also studied, in which the liquid electrolyte was replaced with a thin layer of polyelectrolyte, based on MEH-PPV and potassium iodide.

This paper presents the results of study on titanium dioxide thin films prepared by atomic layer deposition method on a silicon substrate. The changes of surface morphology have been observed in topographic images performed with the atomic force microscope (AFM) and scanning electron microscope (SEM). Obtained roughness parameters have been calculated with XEI Park Systems software. Qualitative studies of chemical composition were also performed using the energy dispersive spectrometer (EDS). The structure of titanium dioxide was investigated by X-ray crystallography. A variety of crystalline TiO2 was also confirmed by using the Raman spectrometer. The optical reflection spectra have been measured with UV-Vis spectrophotometry.

This paper presents research on the deposition of an indium tin oxide (ITO) layer which may act as a recombination layer in a silicon/perovskite tandem solar cell. ITO was deposited by magnetron sputtering on a highly porous surface of silicon etched by the metal-assisted etching method (MAE) for texturing as nano and microwires. The homogeneity of the ITO layer and the degree of coverage of the silicon wires were assessed using electron microscopy imaging techniques. The quality of the deposited layer was specified, and problems related to both the presence of a porous substrate and the deposition method were determined. The presence of a characteristic structure of the deposited ITO layer resembling a "match" in shape was demonstrated. Due to the specificity of the porous layer of silicon wires, the ITO layer should not exceed 80 nm. Additionally, to avoid differences in ITO thickness at the top and base of the silicon wire, the layer should be no thicker than 40 nm for the given deposition parameters. [ABSTRACT FROM AUTHOR]

The article describes the results of a research on the surface morphology and optical properties of Al2O3, ZnO, and TiO2 thin films deposited by atomic layer deposition (ALD) for applications in silicon solar cells. The surface topography and elemental composition were characterised using a scanning electron microscope, and thickness was determined using an optical reflectometer. The samples were structurally examined using a Raman spectrometer. The structural variant was identified: for Al2O3 it is sapphire, for TiO2 it is anatase, and for ZnO it is wurtzite. Possibilities of minimising light reflection using single and double thin film systems below 5% were presented. For the first time, the effectiveness of these thin films on the current-voltage characteristics and electrical parameters of manufactured silicon solar cells was examined and compared. The solar cell with the highest efficiency of converting solar radiation into electricity was obtained for Al2O3/TiO2 and the efficiency of such a photovoltaic device was 18.74%. [ABSTRACT FROM AUTHOR]

The following paper presents the possibility of formation of Pt nanowires, achieved by a three-step method consisting of conformal deposition of a carbon nanotube and conformal coverage with platinum by physical vapour deposition, followed by removal of the carbonaceous template. The characterization of this new nanostructure was carried out through scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD).

Al2O3/TiO2 thin films were deposited onto monocrystalline silicon surfaces using an atomic layer deposition. Their surface morphology and optical properties were examined for their possible use in solar cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness was measured using a spectroscopic reflectometer. The refractive index and the reflection characteristics were determined. First, the optical properties of the Al2O3 thin film and its influence on recombination in the semiconductor were examined. In this way, it can fulfil a double role in a solar cell. Since reflection reduction was only achieved in a narrow range, it was decided to use the Al2O3/TiO2 system. Thanks to this solution, the light reflection was reduced in a wide range (even below 0.2%). [ABSTRACT FROM AUTHOR]

Titanium dioxide thin films have been deposited on silicon wafers substrates by an atomic layer deposition (ALD) method. There optical parameters were investigated by spectroscopic ellipsometry and UV/VIS spectroscopy. A material with a refractive index of 2.41 was obtained. Additionally, in a wide spectral range it was possible to reduce the reflection from the silicon surface below 5%. The Raman spectroscopy method was used for structural characterization of anatase TiO2 thin films. Their uniformity and chemical composition are confirmed by a scanning electron microscope (SEM) energy dispersive spectrometer (EDS). [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to improve the efficiency of dye-sensitized solar cells (DSSCs) which present promising low-cost alternative to the conventional silicon solar cells mainly due to comparatively low manufacturing cost, ease of fabrication and relatively good efficiency. One of the undesirable factor in DSSCs is the electron recombination process that takes place at the transparent conductive oxide/electrolyte interface, on the side of photoelectrode. To reduce this effect in the structure of the solar cell, a TiO2 blocking layer (BL) by atomic layer deposition (ALD) was deposited. Design/methodology/approach: Scanning electron microscope, Raman and UV-Vis spectroscopy were used to evaluate the influence of BL on the photovoltaic properties. Electrical parameters of manufactured DSSCs with and without BL were characterized by measurements of current-voltage characteristics under standard AM 1.5 radiation. Findings: The TiO2 BL prevents the physical contact of fluorine-doped tin oxide (FTO) and the electrolyte and leads to increase in the cell's overall efficiency, from 5.15 to 6.18%. Higher density of the BL, together with larger contact area and improved adherence between the TiO2 layer and FTO surface provide more electron pathways from TiO2 to FTO which facilitates electron transfer. Originality/value: This paper demonstrates that the introduction of a BL into the photovoltaic device structure is an important step in technology of DSSCs to improve its efficiency. Moreover, the ALD is a powerful technique which allows for the highly reproducible growth of pinhole-free thin films with excellent thickness accuracy and conformality at low temperature. [ABSTRACT FROM AUTHOR]

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This paper presents some results of investigations on aluminum oxide Al2O3 thin films prepared by the atomic layer deposition method on polished monocrystalline silicon. It has been described how the technological parameters of the deposition process, like the number of cycles and substrate temperature, influenced the optical properties and morphology of prepared thin films. Their physical and optical properties like thickness, uniformity and refractive index have been investigated with spectroscopic ellipsometry, atomic force microscopy and UV/vis optical spectroscopy. [ABSTRACT FROM AUTHOR]

The paper presents the possibility of using AlO antireflection coatings deposited by atomic layer deposition ALD. The ALD method is based on alternate pulsing of the precursor gases and vapors onto the substrate surface and then chemisorption or surface reaction of the precursors. The reactor is purged with an inert gas between the precursor pulses. The AlO thin film in structure of the finished solar cells can play the role of both antireflection and passivation layer which will simplify the process. For this research 50×50 mm monocrystalline silicon solar cells with one bus bar have been used. The metallic contacts were prepared by screen printing method and AlO antireflection coating by ALD method. Results and their analysis allow to conclude that the AlO antireflection coating deposited by ALD has a significant impact on the optoelectronic properties of the silicon solar cell. For about 80 nm of AlO the best results were obtained in the wavelength range of 400 to 800 nm reducing the reflection to less than 1%. The difference in the solar cells efficiency between with and without antireflection coating was 5.28%. The LBIC scan measurements may indicate a positive influence of the thin film AlO on the bulk passivation of the silicon. [ABSTRACT FROM AUTHOR]

The opportunity of decreasing the development of biofilm on the implant surface is one of the biggest research problems. It is connected with the existing prevention of microorganism hyperplasia. The application of numerous modifications is concerned with surface treatments leading to minimizing bacterial colonization. In the case of non-use antibacterial therapy, this leads to tissue infection. It can lead to a decreased opportunity to fight infection using antibiotherapy. One way is to decrease the increasing biofilm application which requires a method of modification. These techniques ensure properties like homogeneity or repeatability. The structure and chemical composition are changed with methods like CVD (Chemical Vapor Deposition), PVD (Physical Vapor Deposition), sol–gel, or ALD (Atomic Layer Deposition). Antibacterial properties of metals are connected with their impact on proteins and the nuclear proliferation of fibroblasts, causing improvement in biocompatibility and also growth corrosion resistance, and the decline of biofilm adhesion. The prevention of biofilm with medicines and antibiotics is a crowded-out treatment. Traditional methods of preventing biofilm are based on compounds that kill or inhibit the growth of the microbes but at the same time lead to frequent development of resistance to antibiotics. This review summarizes the current knowledge of reducing and preventing the creation of biofilm. [ABSTRACT FROM AUTHOR]

The important research direction in surface engineering and photovoltaics is the development of new materials that can replace the previously used expensive films. A prospective compound is zinc oxide (ZnO), characterized by optical and electrical properties similar to ITO and a lower production cost. One of the key factors influencing the properties of the ZnO thin films is the technique and parameters of their production. The comprehensive investigation results of the influence of ZnO thin-films deposition process temperature on their structure, optical properties, and adhesion are presented in the paper. ZnO films were deposited by the magnetron sputtering method. The structural characteristics of the tested films were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffractometry (XRD) and Raman spectroscopy, while the optical properties of the films were studied by the UV/VIS spectroscopy. Thickness and adhesion measurements of the obtained films were performed using the spectroscopic ellipsometry technique and the scratch test, respectively. The obtained research results showed the influence of the deposition process temperature on the morphology, crystallite size and adhesion of the thin films to the substrate. The effect of process temperature on optical properties, the value of the optical bandgap and crystal structures were analyzed and described. The results of this work have a meaning for the development of surface engineering and may serve as a clue in future studies in the field of modern photovoltaic structures. [ABSTRACT FROM AUTHOR]

The article describes biomaterials and surgical instruments, in particular surgical cutting tools. In addition, the functions of coatings and the layer vapor deposition methods are described. In the experimental component of the study, zinc oxide thin film was deposited on the surgical knife blades by the atomic layer deposition (ALD) method with a varying number of cycles. The structures of the deposited thin films were investigated using a Raman spectrometer and the surface topography of the samples was examined using atomic force microscopy and scanning electron microscopy. The adhesion of the thin films was tested using the micro-scratch method. The corrosion resistance was also tested. Surgical instruments coated with non-allergenic metal oxide coatings, containing metal structures that reduce the growth of bacteria, could significantly decrease the risk of undesirable reactions of the body during and after surgery. [ABSTRACT FROM AUTHOR]

One of the important research directions in the field of photovoltaics is integration with construction. The integration of solar cell systems with a building can reduce installation costs and help optimize the used space. Among the few literature reports on photovoltaic roof tiles, solutions with silicon and thin film solar cells dominate. An interesting solution may be the application of dye-sensitized solar cells. In addition to their interesting properties, they also have aesthetic value. In the classic arrangement, they are constructed using glass with a transparent conductive layer (TCL). This article describes replacing a classic glass counter electrode with an electrode based on a ceramic tile and nickel foil. First, a continuous and homogeneous fluorine-doped tin oxide (FTO) thin film was developed so that the above-mentioned substrate could be applied. The atomization method was used for this purpose. Then, nanocolloidal platinum paste was deposited as a catalytic material using the screen printing method. The electrical parameters of the manufactured DSSCs with and without a counter electrode tile were characterized by measuring their current–voltage characteristics under standard AM 1.5 radiation. A dye-sensitized solar cell integrated with ceramic tiles and nickel foil was produced and displayed an efficiency of over 4%. This solution makes it possible to expand their construction applications. The advantage of this solution is full integration with construction, while simultaneously generating electricity. A dye-sensitized solar cell was built layer-by-layer on a ceramic tile and nickel foil. [ABSTRACT FROM AUTHOR]

Magnesium alloys have been investigated as temporary biomaterials for orthopedic applications. Despite their high osseointegration and mechanical (bone-like) properties, Mg alloys quickly degrade in simulated physiological media. Surface coatings can be deposited onto Mg alloys to slow the corrosion rate of these biomaterials in chloride-rich environments. TiO2 films show high potential for improving the corrosion resistance of magnesium alloys. This article presents the structural observations and corrosion behavior of TiO2 thin films deposited onto a MgCa2Zn1Gd3 alloy using atomic layer deposition (ALD). Surface morphologies were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM), and Raman analysis of the deposited TiO2 films was also carried out. The corrosion behavior of the uncoated alloy and the alloy coated with TiO2 was measured in Ringer's solution at 37 °C using electrochemical and immersion tests. The microscopic observations of the TiO2 thin films with a thickness of about 52.5 and 70 nm showed that the surface morphology was homogeneous without visible defects on the TiO2 surface. The electrochemical and immersion test results showed that the thin films decreased the corrosion rate of the studied Mg-based alloy, and the corrosion resistance was higher in the thicker TiO2 film. [ABSTRACT FROM AUTHOR]