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The purpose of this paper is to demonstrate the influence of material properties and fabrication technique on the performance of an embedded pressure sensor. Based on conducted theoretical analysis a suitable material and technological technique that gave the best behavior of designed sensor was chosen for its fabrication. This is verified on the example of a resonant pressure sensor, designed for operation in the MHz range.

A sensor module is fabricated using the low temperature co‐fired ceramics (LTCC) technology and sputtering technique for electrodes deposition. The module comprises an inductor connected with a variable capacitor formed by the sensor membranes in a parallel LC circuit. An extensive parallel analysis of sensors performance for sensors with thick film (screen‐printed) and thin film (sputtered) electrodes is demonstrated. Mechanical and electrical parameters (Young's modulus and permittivity) of different tape materials that are considered for sensor fabrication are determined at room temperature.

Implementation of the sputtering technique for deposition of the thin film electrodes and usage of tapes with higher elasticity significantly contribute to the increase of the sensor performance (improved sensitivity) compared to designs found in available literature. Experimentally attained results are compared with the ones obtained by analytical calculations achieving good agreement of obtained results.

The improvement of sensor sensitivity by means of evaluation of different tape material and electrode thickness reduction is demonstrated for the first time. The presented results of the sensor equivalent model and the sensor‐antenna system are in good compliance with experimental data determined through measurement.

Drive east from Frankfurt, upstream along the valley of the River Main, and in 25 kilometres or so you will reach Hanau, where once the brothers Grimm lived and collected the folklore which we now know as the famous Tales. Here too, in 1856, Wilhelm Carl Heraeus, a chemist and pharmacist, proprietor of the pharmacy which had carried the family name for many generations, succeeded in producing temperatures approaching 2000°C from an oxy‐hydrogen flame, temperatures sufficiently high to achieve the melting point of platinum and to allow him to melt substantial quantities of this metal for the first time. Hanau was then a centre for the jewellery manufacturing industry (and remains so today) so the smelting of platinum and other precious metals had an immediate commercial relevance.

This paper describes the fabrication of integral screen printed platinum resistance elements. A detailed description is given of the techniques of element manufacture and performance. The paper is finally illustrated by an example of sensor integration into a temperature critical subsystem. This example serves to demonstrate the potential manufacturing economies achieved by this approach.

Thick film technology has been widely used in the past for medium performance packaging solutions, but has been unable to compete with thin‐film technology for high performance requirements. The problems of poor geometrical resolution, together with high dielectric constant and loss, have all contributed to the very limited adopting of thick‐film for advanced applications such as MCMs and microwave. This paper describes a new advanced ceramic based technology using thick‐film conductors and dielectric. Results showing the excellent geometrical properties which result from a combination of novel materials and processing, giving line widths down to 10 microns and via dimensions of 25 micron are presented. The novel dielectric material also provides a dielectric constant of 4, with a loss factor of 1 × 10^−4. This technology allows the fabrication of high density circuits and packages, offering many packaging solutions, including MCM, microwave, sensors and displays, all on one substrate.

On 20 April ISHM‐Benelux held its 1988 Spring meeting at the Grand Hotel Heerlen. This meeting was totally devoted to implantable devices, in particular to the technologies used for these high reliability, extremely demanding devices. For this meeting ISHM‐Benelux was the guest of the Kerkrade facility of Medtronic. Medtronic (headquartered in Minneapolis, USA) is the world's leading manufacturer of implantable electronic devices. Apart from the assembly of pacemakers and heart‐wires, the Kerkrade facility acts as a manufacturing technology centre for Medtronic's European facilities.

This paper aims to present the details of isotactic polypropylene (it-PP) films with a cellular structure (air-cavities) dedicated to pressure sensors. The polymer composites (thin films enriched with 5 and 10 wt% of mineral fillers as Sillikolloid P 87 and glass beads) should exhibit suitable structural elasticity within specific stress ranges. After the deformation force is removed, the sensor material must completely restore its original shape and size.

Estimating the stiffness tensor element (C₃₃) for polymer films (nonpolar space-charge electrets) by broadband resonance ultrasound spectroscopy is a relatively simple method of determining the safe stress range generated in thin pressure sensors. Therefore, ultrasonic and piezoelectric studies were carried out on four composite it-PP films. First, the longitudinal velocity (v_L) of ultrasonic waves passing through the it-PP film in the z-direction (thickness) was evaluated from the ω-position of mechanical resonance of the so-called insertion loss function. In turn, the d₃₃ coefficient was calculated from accumulated piezoelectric charge density response to mechanical stress.

Research is at an early stage; however, it can be seen that the mechanical orientation of the it-PP film improves its piezoelectric properties. Moreover, the three-year electric charge stability of the it-PP film seems promising.

Ultrasonic spectroscopy can be successfully handled as a validation method in the small-lot production of polymer films with the air-cavities structure intended for pressure sensors. The structural repeatability of polymer films is strongly related to a homogeneous distribution of the electric charge on the electret surface.

A screen printable, thick film dielectric materials system, for printing capacitors with Z5U thermal characteristics, has been introduced by Heraeus. IP9300 high K capacitor dielectric is a blendable materials system that permits printing capacitors onto circuits with precise values over a wide range of dielectric constants from K = 3000 to K = 500. It is applied with conventional thick film screening techniques and fired at 850°C. This system is also compatible with some of Heraeus' thick film conductor materials and low temperature overglaze.

Dates: 29–31 May 1991 Venue: De Doelen Conference Centre, Rotterdam, The Netherlands The Benelux Chapter of the International Society for Hybrid Microelectronics will be organising the 8th European Microelectronics Conference. The event will take place at ‘De Doelen’, Rotterdam, The Netherlands, from 29 to 31 May 1991.