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The first results from two collaborative UK programmes assessing the performance of non‐CFC cleaning options for the electronics assembly industry were presented at a one‐day conference on 6 February at the Heathrow Forte Crest Hotel. This was the latest of the long series of meetings on the CFC issue organised by the National Physical Laboratory.

Multilayer aircore inductors fabricated in a range of interconnection technologies which are MCM compatible are presented and compared. These consist of thick‐film, low temperature cofired ceramic (LTCC), printed circuit board (PCB) and fine‐line plated copper on ceramic (copper plating). From a comparison of simulated and measured results, it can be concluded that a predictive design capability has been achieved for inductance and self‐resonant frequency (SRF). Modelling of AC resistance and Q requires further investigation.

This paper will focus on the work which was carried out under the Brite‐EuRAM funded project, COMPRISE (BE 96‐3371), the objective of which was to develop new materials and manufacturing processes to embed passive components (resistors, inductors, capacitors) within printed wiring structures fabricated from laminate materials. For the realisation of integrated resistors, a commercially available planar resistor material is incorporated in different test structures. The technology consists of a copper foil of standard thickness on which a resistive layer is deposited by means of electroless plating. For the realisation of capacitors in multi‐layered PCB structures, significant progress was made in the development and fabrication of very thin laminates. Higher dielectric constants of these laminate materials enable the increase of the capacitance per unit area. For inductors, both aircore (no magnetic material) and magnetic core components have been investigated.

A large group of SMART Group members visited the Henley premises of Electrovert on 9 May. After the welcome and introduction where Mike Judd emphasised Electrovert's commitment to SMT, a number of papers were presented by the Electrovert team during the morning session.

The popular reflow day was repeated at Henley and commenced with Mike Judd giving an overview of current reflow techniques.

Electronics exhibitions are the same the world over, very tiring affairs. If your stand is busy, time flies; if not, the strain is more noticeable.

This conference, in the series being run by the National Physical Laboratory to help the electronics assembly industry consider the problems of CFC phase‐out, was essentially an updated repeat of the event held on 30 April, which had been a complete, standing‐room‐only sell‐out. Surprisingly, this repeat performance also attracted a full house and the format used has proved to be the most popular of all the NPL non‐CFC options conferences.

Thirty‐six people attended this SMART Group Seminar at the Bowler Hat Hotel in Birkenhead, Merseyside, on 20 February 1990. The technical programme in the morning comprised five talks: