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Since the first appearance of high density interconnection systems about ten years ago, researchers have tried to exploit this concept to the full. By introducing new technologies and materials, they have succeeded in building a module that equals wafer scale integration (WSI) in speed and efficiency. However, MCMs have not yet experienced rapid growth and acceptance as a result of the large capital investment and rather small volumes involved. This paper sets out to show that MCMs can be fabricated using technology and processes already in existence at most conventional IC and thin‐film production facilities.

The embedding of passive components such as resistors, capacitors and inductors within printed circuit boards (PCBs) is motivated, to a large extent, by the desire for increased miniaturisation of electronic goods. However, resistors and, to a lesser extent, inductors are heat generating devices, and the temperature developed within PCBs as the result of the operation of embedded passives is a significant aspect of the design of a multilayer PCB. Here we investigate, by simulation, temperature fields associated with operation of embedded resistors. It is shown that for board dimensions less than 2cm × 2cm temperatures achieved are higher than those associated with larger boards having identical structures and identical resistor heat generation. Detailed simulations are used to investigate the sensitivity of the temperature rises associated with embedded resistors to copper track coverage and to thermal coupling of the PCB to ambient on its upper and lower surfaces. The implications of these findings are discussed both in the context of the design of real PCBs and in the context of thermal simulation.

The evolution of today's high speed electronic systems has resulted in the need for modules which are able to provide all chip‐to‐chip interconnection with very fine top level and buried conductor traces, and a dielectric with a very dense via grid pattern. As standard thick film technology is capable of pitches only down to 250 µm, new photoimageable thick film pastes have been developed in order to achieve a higher resolution. These materials allow one to combine the advantages of screen printing as a deposition technique with photolithography for the patterning. The image is produced by exposing the printed paste through a photomask to define either lines or vias, so that a very high resolution (50 (µm pitch), similar to that available in MCM‐D or MCM‐L, can be achieved. This paper describes the processing of the photoimageable dielectric and conductor pastes. As an example of the capability of this technology, a module for electro‐optical interconnection is presented.

Thick film screen printing technology is able to reach a pitch of 250 μm. In an attempt to achieve lower values, two approaches have been developed so far. Both are based on the combination of screen printing as a deposition technique and photolithography for the patterning. The first approach uses photoimageable conductor and dielectric pastes; the second is based on photoimageable dielectric and etching of the fired conductor. In order to obtain a full characterisation of both processes, a test module was designed and manufactured by using the first process and identical test modules were provided by the supplier using the second technology. The design of the test module is based on a two‐layer interconnection pattern including structures for testing cross‐overs, via interconnections with various resolutions (down to 50 μm via size), in order to investigate the limits of these technologies. This paper gives a comparison of these two approaches based on the results of electrical and mechanical measurements performed on both sets of the test modules. Electrical parameters and resolution data are discussed for both processes. The chip and wire assembly method is evaluated to prequalify the technology as an advanced MCM‐C technology for telecoms applications. Finally, the results of reliability tests (humidity ageing and burn‐in) are presented.

This chapter aims to further the conceptual clarity of co-creation, by classifying and exploring the spectrum of non-government actor–led governance arrangements for the co-creation of nature-based solutions (NBS) across different European contexts. Case studies from pilot demonstrators in current Horizon 2020 projects (proGIreg, CLEVER Cities, and EdiCitNet in Italy, Germany, the Netherlands, and the United Kingdom) are used to illustrate collaborative governance arrangements within the operating space of co-creation, delineate respective actor roles, and identify lessons learnt.

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.

George MacMahon has been appointed Product Manager for Thick Film Materials by W. C. Heraeus, Hanau, Germany, to further increase the company's business throughout Europe and beyond. He will help to co‐ordinate technical support for the general sales effort, including the presentation of technical information at meetings and exhibitions.

Following the discussion at our recent Annual General Meeting, a questionnaire was sent out to all members. Almost half of them replied despite the fact that the time allowed for returning the questionnaire had been kept very short. Some members even provided detailed comments.