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This paper aims to select parameters such as temperature thermal stability and temperature coefficient of resistance (TCR) for Ni–P resistive alloys obtained by electroless metallization. Ni–P alloys are used in the manufacture of precision resistors characterized by TCR in the range of ± 10 ppm/K. The correlation of the technological parameters with the electrical properties of resistors enables the accurate prediction of the TCR resistors.

The Ni–P layers were obtained by a continuous process at about 373 K in a solution with the acidity of pH = 2 and then dried for two hours at 393 K. Subsequently, the Ni–P layer was stabilized for two hours in the temperature range of 453-533 K. Resistance was measured with an accuracy of 1 mΩ. TCR was determined with an accuracy of 1 ppm/K in the temperature range 298-398 K. In the next stage of the investigation, the increase in TCR of the Ni–P alloy was correlated with the increase in stabilization temperature. Scanning electron microscope images of the alloy surface were studied to assess grain sizes and to relate the average grain size with TCR values of resistive alloys. The X-ray diffraction analysis was performed to determine the crystallization temperature of Ni–P alloy.

The conducted investigation showed that the TCR increase in alloy is a linear function of stabilization temperature in the temperature range in which transition from amorphous phase to crystalline phases did not occur. TCR increase in Ni–P alloy arises from the increase of average size of grains resulting in decrease of scattering of electrons on grain boundaries. The analysis of alloy composition in chosen fragments of surface shows inhomogeneity growing with decreasing analyzed surface dimensions which proves that, before the stabilization, the structural arrangement of alloy is inconsiderable.

The obtained results are the first attempt to relate the morphology of surface with TCR of alloy and demonstration of linear dependence between an increase in TCR of amorphic Ni–P alloy and stabilization temperature of resistive layer. Such correlations are not described in available literature.

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.

This paper aims to present the possibility of computer-aided technology of chemical metallization for the production of electrodes and resistors based on Ni-P and Ni-Cu-P layers.

Based on the calculated parameters of the process, test structures were made on an alumina substrate using the selective metallization method. Dependences of the surface resistance on the metallization time were made. These dependencies take into account the comparison of the calculations with the performed experiment.

The author created a convenient and easy-to-use tool for calculating basic Ni-P and Ni-Cu-P layer parameters, namely, surface resistance and temperature coefficient of resistance (TCR) of test resistor, based on chemical metallization parameters. The values are calculated for a given level of surface resistance of Ni-P and Ni-Cu-P layer and defined required range of changes of TCR of test resistor. The calculations are possible for surface resistance values in the range of 0.4 Ohm/square ÷ 2.5 Ohm/square. As a result of the experiment, surface resistances were obtained that practically coincide with the calculations made with the use of the program created by the authors. The quality of the structures made is very good.

To the best of the authors’ knowledge, the paper presents a new, unpublished method of manufacturing electrodes (resistors) on silicon, Al₂O₃ and low temperature co-fired ceramic substrates based on the authors developed computer program.

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 purpose of this paper is to characterize electrical parameters of amorphous Ni‐P resistive layers used for fabrication of precise resistors.

Ni‐P resistive layers were produced by the chemical process in water solution using Ni^2 + and H₂PO₂⁻ ions. The paper presents the results of the studies concerning the influence of bath acidity and conditions of thermal stabilization on the structure and temperature coefficient of resistance of Ni‐P alloy.

The temperature coefficient of resistance of amorphous Ni‐P layers was found to depend significantly on the parameters of chemical metallisation process. It was stated that the changes of through‐casing resistivity versus the acidity of technological solution have roughly parabolic characteristics.

In this paper, it was at first explained how the changes of the structure of Ni‐P resistive layers depend on their temperature coefficient of capacitance.

This paper aims to present the possibility of the technology of chemical metallization for the production of contact of photovoltaic cells. The developed technology allows you to perform low-cost contacts in any form.

The study used a multi- and monocrystalline silicon plates. On the surface of the plates, the contact by the electroless metallization was made. After metallization stage, annealing process in a temperature range of 100-700°C was conducted to obtain ohmic contact in a semiconductor material. Subsequently, the electrical parameters of obtained structures were measured. Therefore, trial soldering was made, which demonstrated that the layer is fully soldered.

Optimal parameters of the metallization bath was specified. The equations RS = f (metallization time), RS = f (temperature of annealing) and C-V characteristics were determined. As a result of conducted research, 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 silicon plate is technology presented below in the following steps: masking, selective activation and nickel-plating of activated plate. Such obtained metal layers have great variety in application and, in particular, can be used for the preparation of electric terminals in silicon solar cell.

The paper presents a new, unpublished method of manufacturing contacts in the structure of the photovoltaic cell.

This paper aims to present the results of measurements of the photovoltaic structures made by electroless selective metallization technology. The developed technology provides low-cost contacts in any form, and parameters of photovoltaic cells made in this technology provide reliable results, comparable with those usually used.

In this paper, photovoltaic cells with contacts based on Nip and NiCuP alloy were performed. As a substrate, mono- and multicristaline silicon was used. After photovoltaic cells have been prepared, sheet resistance of the contact layers and electrical parameters were measured. Composition and structure of contact layers were also measured.

Obtained results of sheet resistance and contact layers are repeatable and comparable with previously published results. Electrical parameters of the photovoltaic cells made are comparable with used substrate and technologies. The authors have also noticed that the costs of the electroless metallization which is used to make contact layers is lower than metallization made by thick film or vacuum deposition technologies.

The paper presents new, unpublished results of electrical parameters of photovoltaic cells with contact layers made by electroless metallization. The original idea is the usage of metallization in an acidic solution (pH = 2). In this proposed technology, photovoltaic cells on mono- and multicrystalline silicon plates were performed.