Search results
1 – 6 of 6Milena Kiliszkiewicz, Dariusz Przybylski, Jan Felba and Ryszard Korbutowicz
The purpose of this paper is to analyze the individual steps during the printing of capacitor structures. The method of substrate preparation, the obtained roughness of conductive…
Abstract
Purpose
The purpose of this paper is to analyze the individual steps during the printing of capacitor structures. The method of substrate preparation, the obtained roughness of conductive and dielectric layers are examined. Moreover, the capacitances of the obtained capacitors were examined.
Design/methodology/approach
Surface roughness and microscopic analysis were used to assess the quality of printed conductive structures. Two criteria were used to assess the quality of printed dielectric structures: the necessary lack of discontinuity of layers and minimal roughness. To determine the importance of printing parameters, a draft experimental method was proposed.
Findings
The optimal way to clean the substrate has been determined. The most important parameters for the dielectric layer (i.e. drop-space, table temperature, curing time and temperature) were found.
Research limitations/implications
If dielectric layers are printed correctly, most problems with printing complex electronic structures (transistors, capacitors) will be eliminated.
Practical implications
The tests performed identified the most important factors for dielectric layers. Using them, capacitors of repeatable capacity were printed.
Originality/value
In the literature on this subject, no factors were found which were responsible for obtaining homogeneous dielectric layers.
Details
Keywords
Abstract
Details
Keywords
Tomasz Matusiak, Arkadiusz Dabrowski and Leszek Golonka
The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.
Abstract
Purpose
The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.
Design/methodology/approach
Graphite-based resistors were made of thick-film pastes with different graphite-to-glass mass fraction were prepared and examined. Sheet resistance, temperature coefficient of resistance, impact of humidity and short-term overload were investigated. The properties of the layers fired in atmospheres of air at 550°C and nitrogen at 875°C were compared.
Findings
Graphite-based resistors with various graphite-to-glass ratios made possible to obtain a wide range of sheet resistance from single O/square to few kO/square. These values were dependent on firing atmosphere, paste composition and the number of screen-printed layers. The samples made of paste with 1:1 graphite-to-glass ratio exhibited the temperature coefficient of resistance of about −1,000 ppm/°C, almost independently on the firing atmosphere and presence of a top coating. The resistors fired in the air after coating with overglaze, exhibited significantly lower sheet resistance, reduced impact of humidity and improved power capabilities.
Originality/value
In this paper, graphite-based resistors for applications in typical high-temperature cermet thick-film circuits were presented, whereas typical graphite-based resistors were fabricated in polymer thick-film technology. Owing to very low cost of the graphite, the material is suitable for low-power passive circuits, where components are not subjected into high temperature, above the typical temperature of operation of standard electronic components.
Details