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This paper outlines methods and results of wetting, leaching and adhesion analyses on copper thick film conductors over alumina and multilayer glasses after different processing conditions. The intention is to provide a better background for evaluating and optimising materials and processing conditions in copper thick films and working out quick, reliable and quantitative methods for better characterisation of copper conductors in production. For these reasons the following methods were used: (a) wetting and leaching analyses with a scanning wetting balance, working in nitrogen, (b) pull tests with solder contacts on copper thick film conductors after soldering, ageing and thermal cycling, and (c) some additional surface analyses (REM, EDX, Auger) for a better understanding of copper pastes and their material interactions, when processed under different conditions. The results are summarised under three general aspects: surface structure and wetting of copper thick films, wetting and leaching of various copper thick films after different processing conditions, and finally the influence of different wetting properties of such surfaces on the solder adhesion strength after soldering, ageing and thermal cycling. The results give good insight into the various interactions of copper thick films with their substrate materials and confirm the ability of the described wetting and leaching analyses for these purposes.

A simple interaction‐potential model has been established to calculate the higher order elastic constants of intermetallic YbAl2 in the temperature range from 10‐300K. Temperature dependent second and third order elastic constants are used for the determination of the ultrasonic attenuation, velocity, Grüneisen numbers, Acoustic‐coupling constants, and thermal relaxation time at the different temperatures. Temperature dependency of the ultrasonic properties of YbAl2 is similar at low temperatures to that of pure metals and the low carrier heavy fermion systems ‐ LaSb, YbAs and YbP having simple NaCl‐type structures. Thermal energy density makes significant contribution to the total attenuation in the compound at the higher temperatures from 100‐300K. Effect of the magnetic field on the ultrasonic attenuation is also evaluated using the magneto resistance data. At 100K, the effect of the magnetic field becomes insignificant. The attenuation decreases with the field at 3K to 50K.

This paper outlines some general aspects of materials and processes for reliable soldering of chip components and presents some new results on testing of wettability and leaching of thick films, thermal fatigue of solders and the reliability of solder joints on different thick film metallisations.

A month or so after the Stresa meeting, the French ISHM chapter, organising a session on ‘Gallic inks’ (!), summoned me to deliver some comments on the 5th European Hybrid Microelectronics Conference. Although it was only a matter of interlude during this technical session, I felt the task quite a difficult one. It became a hazardous project when Brian C. Waterfield kindly asked me to let what is in fact a personal opinion—my personal opinion, standing back from my daily work—appear in Hybrid Circuits. I'll do my best.

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.

The paper gives a review of the present knowledge of the piezoresistive properties of thick‐film resistors (TFRs) and shows how they have been exploited for the implementation of strain‐related physical‐quantities transducers. Two types of device are described in some detail. These achievements were made possible by a proper choice of resistive and conductive pastes and their firing conditions, since only in this case useful piezoresistive properties can be achieved that make TFR strain gauges competitive with metal and semiconductive materials. After examining some correlations between gauge factors, composition and structure of TFRs, new data are presented showing how the strain sensitivities may be changed by varying the peak firing temperature, dwell time and the nature of the chemical elements which diffuse from terminations in the films.

Organised by ISHM‐France, this event is aimed at suppliers, manufacturers, and users of hybrid microelectronic circuits. The aim of the conference is to present information on the latest innovations and trends in microelectronics. Twelve technical papers selected by ISHM‐France will be presented in two sessions.

ISHM‐Benelux held its 1987 Autumn Conference on 29 October, at the Antwerp Crest Hotel. This one‐day meeting focused on applications of hybrid circuit technology in various fields of electronic and related industries.

The ISHM‐Benelux Chapter will organise a one‐day conference at the Antwerp Crest Hotel, on Thursday 29 October 1987. The conference will be aimed at applications of hybrid circuits rather than technology.

Introduces a special issue on globalization and the welfare state. Asserts that economic globalization constrains national economic and social policy far more now than ever before, although the level of international trade has not increased that much compared to levels at the beginning of this century. Talks about the political consequences of economic globalization, particularly welfare state retrenchment in the advanced capitalist world. Outlines the papers included in this issue – comparing welfare system changes in Sweden, the UK and the USA; urban bias in state policy‐making in Mexico; and the developing of the Israeli welfare state. Concludes that economic globalization has a limited effect in shaping social welfare policy in advanced capitalist countries; nevertheless, recommends further research into which aspects of economic globalization shape social welfare policy.