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The main aim of this study was a preparation development of dopant solution (DS) which can be deposited by a spray-on method and subsequently allows obtaining the n+ emitter layer with surface resistance in the range of 65-80 Ω⁻¹. The intention of chosen spray-on method was to gain a cheaper way of dopant source deposition, compared to the commonly used methods, which is of particular importance for the new low-cost production processes.

This paper presents the sequence in producing a spray-on glass solution (DS) with very high concentration of phosphorus, which allows to perform diffusion doping at relatively low temperatures. DS contained deionized water, ethyl alcohol, tetraethoxysilane and othophosphoric acid.

The sequence in producing a DS was performed with respect to enabling the application to silicon wafers by spray-on method. Furthermore, the equations defined density and viscosity of DS in term of storage time were referred to determine the possibility of applying this solution by spray-on method. Besides, the dependence of the emitter surface resistance on the doping (diffusion) time was determined. Accordingly, optimal process conditions were specified.

The paper presents a new, so far unpublished composition of DS with very high concentration of phosphorus, which can be applied using a spray-on method. Moreover, original are also investigations respecting some properties of obtained DS relative to storage time.

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.

The purpose of this study is comparison of the diffusion processes performed using the commercial available dopant paste made by Filmtronics and the original prepared liquid dopant solution. To decrease prices of industrially produced silicon-based solar cells, the new low-cost production processes are necessary. The main components of most popular silicon solar cells are with diffused emitter layer, passivation, anti-reflective layers and metal electrodes. This type of cells is prepared usually using phosphorus oxychloride diffusion source and metal pastes for screen printing. The diffusion process in diffusion furnace with quartz tube is slow, complicated and requires expensive equipment. The alternative for this technology is very fast in-line processing using the belt furnaces as an equipment. This approach requires different dopant sources.

In this work, the diffusion processes were made for two different types of dopant sources. The first one was the commercial available dopant paste from Filmtronics and the second one was the original prepared liquid dopant solution. The investigation was focused on dopant sources fabrication and diffusion processes. The doping solution was made in two stages. In the first stage, a base solution (without dopants) was made: dropwise deionized (DI) water and ethyl alcohol were added to a solution consisting of tetraethoxysilane (TEOS) and 99.8 per cent ethyl alcohol. Next, to the base solution, orthophosphoric acid dissolved in ethyl alcohol was added.

Diffused emitter layers with sheet resistance around 60 Ω/sq were produced on solar grade monocrystalline silicon wafers using two types of dopant sources.

In this work, the diffusion processes were made for two different types of dopant sources. The first one was the commercial available dopant paste from Filmtronics and the second one was the original prepared liquid dopant solution.

The aim of the article is to propose BPMN extensions that facilitate the modeling of Clinical Pathways in a way that enables for various groups of users, the transfer of a much wider range of information in the form of process models without compromising their readability and usefulness.

The paper uses the design science research methodology (DSRM) and covers phases of a design-oriented research project extending BPMN notation for clinical pathway modeling.

The article proposes extensions of BPMN in 5 areas, enabling standardization of the description of business processes of different natures and complexity and in turn meeting the needs and requirements of modeling clinical pathways and, more broadly speaking, knowledge-intensive business processes (kiBPs) in general. As shown by the evaluation carried out among medical personnel, the proposed extensions allow for the readable transfer of a considerably larger body of information relevant to the planned, conducted and assessed therapy (kiBPs) than the current BPMN 2.0 standard.

The BPMN extensions proposed in the article fill the gaps in this notation and do not require users to know many notations, which in practice is unrealistic. Defined extensions to the BPMN specification makes it possible to standardise the description of processes of different natures and levels of complexity. In this way, both simplified models (and views of models) dedicated to users unfamiliar with BPMN and models (or views) using advanced possibilities provided by BPMN can be based on one standard, even if they use only a small part of its possibilities.

The purpose of this paper is to analyse the dynamics of a thermal field generated in a tubular bus with rated current by using two models of electrical resistivity of copper.

The boundary-initial problem of the modified heat equation was formulated for the tubular bus. Analytical solutions were obtained by means of Green’s functions as the kernels of the integral operator inverse to the corresponding differential operator. The results were presented graphically and verified using the finite element method. The calculations were made by considering the example of the Storm Power Components tubular bus (USA).

Analytical field models were used to determine time- and space-variable heating curves, time constants and steady-state current ratings.

This paper is related to the structure of a hollow cylinder. Other bus sections can be taken into account by using the coordinate systems of different curvilinear orthogonal symmetry.

Using the analytical method, the influence of the variable (temperature dependent) electrical resistivity on some important parameters and characteristics of the tubular bus was investigated. The system was considered as an element with distributed parameters.