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Passive conducting elements are the important parts of textronic systems. This paper aims to study a possibility of creating well-conducting and durable elements in textile materials by combining two technologies – physical vapour deposition (PVD) and laser patterning.

Thin conducting metallic layers on common fabrics do not provide satisfactory resistance to bending and stretching; therefore, selected textile composite materials have been proposed as a substrate. The conducting elements were produced in two stage process – deposition of thin metallic layer on textile composite and creating conducting elements by laser patterning. Laser ablation process was optimized using modelling in Comsol Multiphysics package. Properties of conducting structures were investigated experimentally and by modelling.

This paper confirms the correctness of the choice of the textile composite as a substrate for conducting elements. The results have shown that combining PVD deposition of thin metallic layer and controlled laser ablation allow creating passive elements such as resistors, inductive coils and heaters. Computer simulations conducted in the Comsol Multihysics environment enabled to determine the temperature distribution around the heaters and to describe the dynamics of its changes. The obtained results allow to shorten time of the optimization process of structures with different geometry and assumed temperature distribution.

The novelty of this research can be summarized as following: choosing of textile composites as substrates for conductive elements instead of textiles used so far in textronics; creating conductive structures on textile composites using combined technologies, PVD and laser patterning, for the first time; modelling of laser ablation process of thin metallic layer; and optimization of properties of conducting elements by computer modelling.

High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.

A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.

The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.

The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.

The paper aims to show application of the electrochemically deposited coatings for thickening of the screen printed electric paths potentially applied in photovoltaic cells.

The electric paths were screen printed with the use of silver-based paste. The paths were thickened by electrodeposition of thin copper layer in potentiostatic regime from surfactant-free plating bath. The morphology and surface quality of the paths were studied by imaging with scanning electron microscopy.

The electric paths can be thickened successfully, but quality for the screen printed substrate determines quality of deposited layer. The EDX analysis confirmed that the deposited copper layer covered uniformly the printed paths.

The adhesion of the copper-covered path to the silicon wafer surface depends on adhesion of the original screen printed path.

This paper confirms that electrodeposited copper can be applied for screen printed silver paths thickening in a controllable way.

The paper aims to present a research on the impact of the stabilization process of a thin metallic layer (Ni-P) produced on a ceramic surface (Al₂O₃) by means of electroless metallization on its electric parameters and structure. On the basis of the research conducted, the existence of a relationship between resistance (R) and the temperature coefficient of resistance (TCR) of the test structure with a Ni-P alloy-based layer and the temperature of stabilization was proposed.

Metallic Ni-P layers were deposited on sensitized and activated substrates. Metallization was conducted in an aqueous solution containing two primary ingredients: sodium hypophosphite and nickel chloride. The concentration of both ingredients was (50-70) g/dm³. The process lasted 60 min, and the metallization bath pH was kept at 2.1-2.2, whereas the temperature was maintained at 363 K. The thermal stabilization process was conducted in different temperatures between 453 and 623 K. After the technological processes, the resistance and TCR of the test structures were measured with a micro ohmmeter. The composition and the morphology of the resistive layer of the structures examined was also determined.

The dependence of the resistance on the temperature of the stabilization process for the temperature range 553 to 623 K was described using mathematical relationships. The TCR of test resistors at the same thermal stabilization temperature range was also described using a mathematical equation. The measurements show that the resistive layer contains 82.01 at.% of nickel (Ni) and 17.99 at.% of phosphorus (P).

The results associate a surface morphology Ni-P alloy with the resistance and TCR according to temperature stabilization. The paper presents mathematical relationships that have not been described in the literature available.

The purpose of this paper is to present the possibility of technology of chemical metallization for the production of electrodes and resistors based on Ni–P alloy on silicon (Si), alundum (Al₂O₃) and low temperature cofired ceramic (LTCC) substrates. The developed technology provides low cost in any form.

During the study monocrystalline Si plates and Al₂O₃ and LTCC substrates were used. On the surface of the substrates, the electrodes (resistors) by the electroless metallization were made. Subsequently, the electrical parameters of obtained structures were measured. Afterwards, trial soldering was made to demonstrate that the layer is fully soldered.

Optimal parameters of the metallization bath were specified. As a result of the research conducted, it has been stated that the most appropriate way leading to the production of soldered metal layers with good adhesion to the portion of selectively activated Si plate and Al₂O₃ and LTCC substrates comprises the following technology: masking, selective activation, nickel-plating of activated plate. Such obtained metal layers have a great variety of application; in particular they can be used for the preparation of electric contacts in Si solar cells, production of electrodes and resistors and production of electrodes in thermoelectric structures.

The paper presents a new, unpublished method of manufacturing electrodes (resistors) on Si plate and Al₂O₃ and LTCC substrates.

The aim of this paper is to present results of investigations carried out on the front electrode of solar cells. Nowadays, most worldwide solar cell production is dominated by monocrystalline and polycrystalline silicon as a base material. In such cells, the electrical carriers are collected by the system of metallic paths fabricated on a silicon surface. One possible way to increase cell efficiency and reduce the production costs of solar modules is to replace the expensive silver by cheaper copper in front metallic electrodes.

The paper presents results of investigations performed on the front electrode of the solar cell. The investigations were focused on the modification of typical screen printing fabrication of the thin electrical finger paths of the front solar cell electrode. The resulting contacts were characterized morphologically (the dimensions and geometry of the front contacts) by scanning electron microscopy. The composition of finger path covered with copper was analyzed using energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy techniques.

In this work, the front electrodes were screen printed with the use of conventional silver-paste on a p-type Cz–Si-textured wafer with a n+ emitter and with an antireflection coating. After that, the fired front electrode was electroless coated with copper. The electroless copper deposition was performed in two stages. First, the surface of the photovoltaic cell was dipped in an aqueous solution of CuSO₄ and then dried in air at room temperature. When the surface dried, the cell was immersed in hydrogen fluoride solution (5 per cent) for 1 s followed by rinsing in deionization water.

The experiments confirmed the potential application of copper as an additional layer of the solar cell front metal electrode. On the one hand, this process is very simple and, on the other, the authors demonstrate a problem with the mechanical stability of the covered paths leading to electrode delamination.

The purpose of this paper was the investigation of transparent conducting oxide (TCO) applied as an additional part of front metal electrode of crystalline silicon solar cell. Transparent conducting oxides are widely used as counter electrodes in a wide range of electronics and optoelectronics applications, e.g. flat panel displays. The most important optical and electrical requirements for TCOs are high optical transmittance and low resistivity. This low resistivity might invoke the possibility of increasing the distance between the fingers in the solar cell front electrode, thus decreasing the total area covered by metal and decreasing the shadowing loss.

In the present work, thin films of indium-tin-oxide (ITO) as a transparent counter electrodes, were evaporated on the surface of silicon n+-p junction structures used in solar cells. The influence of the properties of ITO electrode on the electrical performance of prepared solar cells was investigated through optical and electrical measurements. The discussion on the influence of deposition conditions of the TCO films on recombination of the photogenerated electrical charge carriers and solar cell series resistance was also included.

In this work, the fingers lines 100 μm width were screen-printed on the c-Si wafer with ITO layer. Monocrystalline silicon 25 cm 2,200-μm-thick wafers, were used for this testing. The usefulness of the ITO films as antireflection coating was discussed as well. It is commonly known that electrical performance of solar cells is limited by surface passivation. Despite this, the obtained results for ITO-Si structures showed relatively high value of short circuit current density (Jsc) up to 33 mA/cm2.

Our experiments confirmed the potential of application of ITO as anti-reflection coating (ARC) layer and according to their low resistivity possible use as a functional counter electrodes in photovoltaic structures.

Different metals have been processed using laser‐based solid freeform fabrication (SFF) processes but very little work has been published on the selective laser melting (SLM) of gold (Au). The purpose of this paper is to check the properties of gold powder and identify suitable processing parameters for SLM of 24 carat gold powder.

A full factorial approach was used to vary the processing parameters and identify suitable processing region for gold powder. The effects of laser processing parameters on the internal porosity of the multi‐layer parts were examined.

The gold powder was found to be cohesive in nature with apparent and tap densities of 9.3 and 10.36 g/cm³, respectively. The reflectance of gold powder was found to be 85 per cent in the infrared range. A very narrow good melting region was identified for gold powder. The balling phenomenon was observed at both low and high scan speeds. The size of droplets in the balling region tended to increase with increasing laser power and decreasing scan speeds. The porosity in gold multi‐layer parts was found to be the minimum for a laser power of 50 W and scan speed of 65 mm/s where most of the porosity was found to be inter‐layer porosity.

This research is the first of its kind directly processing 24 carat gold using SLM, identifying the suitable processing parameters and its effect on the internal porosity and structure of multi‐layer parts.

The purpose of this paper is to study the repeatability of path manufacturing in the drop on demand inkjet printing process and the influences of environmental and application factors on path resistance.

Paths were printed as multiline paths in packets one-, two- and three-layer paths on polyimide substrates using nanoparticle silver ink. The sintering conditions were determined experimentally. The paths were subjected to climatic and shock exposures and to bending processes. The resistance, profile and width of the paths were measured and analyzed. The temperature distribution for electrically heated paths was measured to identify the defects.

This research shows the repeatability of printing processes and identifies the sources that cause diversification in path parameters after the whole technological process. The influence of shock, climatic and mechanical exposures on path electrical properties is indicated. An effective method for identifying defects thermally is shown.

The research could have limited universality by arbitrarily use of substrate material, ink, printhead, process parameters and kind of sample exposures.

The research includes practically useful information about the width, thickness, defects and resistances and their changes during a typical application for a path printed with different technological parameters.

This research presents the results of original empirical research on problems concerning the manufacture of paths with uniform parameters and shows how path parameters will change under exposures that may occur in a typical application. The research combines both production and application aspects.

The purpose of this paper was investigation and comparison of electrical and optical properties of crystalline silicon solar cells with ITO or TiO₂ coating. The ITO, similar to TiO₂, is very well transparent in the visible part of optical radiation; however, its low resistivity (lower that 10-3 Ohm/cm) makes it possible to use simultaneously as a transparent electrode for collection of photo-generated electrical charge carriers. This might also invoke increasing the distance between screen-printed metal fingers at the front of the solar cell that would increase of the cell’s active area. Performed optical investigation showed that applied ITO thin film fulfill standard requirements according to antireflection properties when it was deposited on the surface of silicon solar cell.

Two sets of samples were prepared for comparison. In the first one, the ITO thin film was deposited directly on the crystalline silicon substrate with highly doped emitter region. In the second case, the TCO film was deposited on the same type of silicon substrate but with additional ultrathin SiO₂ passivation. The fingers lines of 80 μm width were then screen-printed on the ITO layer with two different spaces between fingers for each set. The influence of application of the ITO electrode and the type of metal electrodes patterns on the electrical performance of the prepared solar cells was investigated through optical and electrical measurements.

The electrical parameters such as short-circuit current (J_sc), open circuit voltage (Voc), fill factor (FF) and conversion efficiency were determined on a basis of I-V characteristics. Short-circuit current density (J_sc) was equal to 32 mA/cm² for a solar cell with a typical antireflection layer and 31.5 mA/cm² for the cell with ITO layer, respectively. Additionally, electroluminescence of prepared cells was measured and analysed.

The influence of the properties of ITO electrode on the electrical performance of crystalline silicon solar cells was investigated through complex optical, electrical and electroluminescence measurements.