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This paper presents an experience in designing a printed circuit board prototype as part of a general surface mount investigation for commercial electronics application. The point of view is that of a low volume assembler of relatively large, complex PC boards which use standard components. Three prototype versions were designed using different criteria. FR‐4 substrate was used for all of the designs. A comparison of the three designs with the through‐hole version indicates that the economic success of surface mounted printed circuit assemblies is heavily dependent on the physical design of the printed circuit board. Some of the aspects of a surface mounted circuit assembly that are discussed include design philosophy and tools, printed circuit board fabrication and bare board test. Design practices that would ideally utilise the small size of surface mount components are contrasted with those practices necessary to provide low cost and manufacturability of the printed circuit board.

Nowadays, using of material properties for monitoring of phenomena occurring in the surrounding environment is very desirable. Taking into account the dynamic development of Internet of Things and the technological development of printed electronics, research into the using of printed electronic components for sensor applications can be one of the most prominent directions of searching for new innovative solutions. Among others, it is possible to apply them to produce the strain gauges, as well as for construction of advanced sensors for medical applications. The goal of this paper is to present the possibilities and using different constructions of embedded polymer thick-film resistors as the sensors of tension or strain.

The investigations were based on the polymer thick-film resistors made of carbon or carbon–silver inks printed on copper pads made on FR-4 material on two sides. The longitudinal samples laminated with resin-coated copper foil material and without lamination were bent on a strength machine. During the tests, the resistors depending on their placement were stretched or compressed. Some of the samples were also tested under high pressure. Under the influence of applied stresses, there was a reversible change in electrical resistance, which was monitored.

The study showed that the polymer thick-film resistors are characterized by a measurable piezoresistive effect. By analyzing the value of the observed resistance changes, a magnitude of strain or pressure can be worked out. During the bending, the piezoresistive effect depends on the location and orientation of the resistor. After stopping of the mechanical strains, the electrical resistance of the resistive elements does not return exactly to the initial value. This is probably related to the substrate material and the resistive paste composition. The results are very promising and further research will be done.

The results provided information about the piezoresistive effect of polymer thick-film resistors printed on the deformable substrate which could be interesting for engineers involved in printed sensor development dedicated for different fields of application. This phenomenon can be used to manufacturing cheap and uncomplicated sensors to monitor deformation. There are several aspects to be solved, but with the use of new types of resistive pastes and substrates, there is a potential possibility of using such resistors as sensors.

The purpose of this paper is to present thermal properties of palladium-carbon films prepared by physical vapour deposition (PVD)/chemical vapour deposition (CVD) methods.

Thin palladium-carbon films were prepared at Tele- and Radioresearch Institute. Test structures containing palladium-carbon films and titanium electrodes were made. Temperature-resistance characteristics were measured.

The results show strong temperature dependence of modified carbon film resistance. The dependence is stable, and so modified carbon films can be applied for various electronic applications.

The paper presents thermal properties of thin palladium-carbon prepared by original PVD/CVD method at Tele- and Radioresearch Institute.

This study aims to ameliorate the strength and uniformity of the magnetic field in the air-gap of quartz flexible accelerometers. Quartz flexible accelerometers (QFAs), a type of magneto-electric inertial sensors, have wide applications in inertial navigation systems, and their precision, linearity and stability performance are largely determined by the magnetic field in operation air-gap. To enhance the strength and uniformity of the magnetic field in the air-gap, a magnetic hat structure has been proposed to replace the traditional magnetic pole piece which tends to produce stratiform magnetic field distribution.

Three-dimensional analysis in ANSYS workbench helps to exhibit magnetic field distribution for the structures with a pole piece and a magnetic hat, and under the hypothesis of cylindrical symmetry, two-dimensional finite element optimization by ANSYS APDL gives an optimal set of dimensions of the magnetic hat.

Three structures of the QFA with a pole piece, a non-optimized magnetic hat and an optimized magnetic hat are compared by the simulation in ANSYS Maxwell and experiments measuring the electromagnetic rebalance force. The results show that the optimized hat can supply stronger and more uniform magnetic field, which is reflected by larger and more linear rebalance force.

To the authors ' knowledge, the magnetic hat and its dimension optimization have rarely been reported, and they can find significant applications in designing QFAs or other similar magnetic sensors.

The European Commission has decided that from the second half of 2006 only lead‐free solder pastes will be permitted for use in the electronics industry. Earlier results of testing showed that lead‐free solder pastes may not be appropriate for both printed‐circuit‐board (PCB) and hybrid‐circuit applications, because of the materials' compatibility with the soldering process and with the solder pads. The basic properties of the investigated pastes show which of the tested solder pastes can be used for both applications. After selection of the appropriate solder pastes, reliability tests were conducted. The surface insulation resistance was tested for both the hybrid circuits and PCBs, whereas the mechanical strength of the soldered joints of components was only tested for the PCBs.