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In manufacturing of multichip modules based on die ICs, the first-step soldering temperature shall not be higher than 270 °С owing to a large number of successive steps. Besides, due to a large number of contact pads of small geometric size and their short spacings the solder layer of the required thickness can generally be formed on them by electrodeposition only. The paper contains the findings of the research into the process of electrodeposition of a tin-lead alloy characterized by a high lead content (of more than 80 % by mass), run to form a layer of a solder characterized by a melting temperature of more than 270 °С and intended for mounting die chips in the multichip module technology. The formula of a fluoroborate electrolyte delivering the specified chemical composition of the alloy has been proposed, and the relationship existing between the chemical composition of the alloy and current density during alloy formation has been found. The optimum current density has been determined, which is equal to (1-1.2) А/dm. This current density produces dense fine-grained layers characterized by a surface melting temperature of about 290-295 °С.

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The results of investigating the compositions for manufacture of the thick-film resistive elements with high-temperature coefficient of resistance (TCR) for application as thermo-resistive gauges have been presented. In the investigated compounds a powder based on boride-silicides of molybdenum as a spending phase and the powders of glasses of the Mn-O-B2O3-SiO2 system as a glass binder have been used. The areas of structures of glasses and resistive compositions for producing the resistive elements with the TCR value of -2500 - 3000ּ10-6K-1 order have been given.

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