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The main aim of this paper is to investigate the influence of the cavity coverage on the printed circuit boards (PCB) to the resonant frequency, acceleration and displacement.

Tests were realized on four PCBs with different cavity areas. Frequency range of tests was between 10 and 2,000 Hz with 0.3 g acceleration amplitude. In addition, more simulations were performed to check different setups of the boards.

From the calculated and measured data, it is clear that with the larger cavity area the resonance frequency drops. In case a greater number of components placed in cavities are needed on board, it is appropriate to use multiple smaller cavities than the bigger ones.

Results in this paper could be very useful for PCB manufacturers and designers during designing of the new PCBs with cavities for dipped components.

The purpose of this paper is to focus on a description of reliable bonding technique of zero-shrink low-temperature co-fired ceramic (LTCC) and alumina ceramics. LTCC is widely used for manufacturing electrical systems in 3D configuration. LTCC substrates were so far bonded with alumina ceramics using additional adhesive layers with subsequent firing or curing cycle. With the advent of the zero-shrink LTCC substrates, it is now possible to bond unfired substrates with other fired substrates, for example fired LTCC or alumina substrates. Alumina substrate in combination with LTCC brings advantages of good thermal conductivity for usage in heating elements or packaging.

The test structure contains a thick-film pattern for verification of the compatibility of the bonding process. We have used two methods for bonding the substrates: cold chemical lamination (CCL) and thermo compression method, using a dielectric thick-film paste as the adhesive. Optical microscopy, scanning electron microscopy and electric testing of the screen-printed patterns were used for verification of the bonding quality.

The thermo-compression method gave poor results in comparison with the CCL method. The best quality of lamination was achieved at room temperature combined with low pressure for both types of bonding materials. In addition, a possibility of using this bonding method for sensor fabrication was investigated. The ceramic pressure sensor samples with a cavity were created.

The possibility of bonding two different ceramic materials was investigated. A new approach to ceramic bonding showed promising results with possible use in sensors.

Investigates the influence of land pattern pad designs and solder volume on reliability of solder joint attachments for surface mounted passive chip devices. All boards were thermal cycled and periodically tested to induce a damage mechanism in less time than in real service use. The difference in the number of failures for different pad designs and for different stencil thicknesses was recorded. Failure analysis with respect to stencil thickness and position of resistor on board is studied and a new approach for the comparison of resistor reliability by using Weibull distribution is shown. The time period for this testing was kept to a minimum by accelerated ageing of tested samples. This test aims to predict the onset of the wear‐out period under the normal conditions of service. The results from measurements during thermal cycling are also given and the basic rules for practical application are summarised.

On 8 October 1992 the ISHM‐Benelux Chapter organised a one‐day conference entitled ‘New Trends in Electronic Packaging and Interconnection’ which took place in the Holiday Inn, Gent, Belgium. This conference was attended by 45 participants from the Benelux countries and Great Britain.