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This paper describes some recent innovations in design, process and materials in printed circuit laminate technology, which can lead to significant paradigm shifts in the design and application of electronic products. The traditional roles for printed circuit cards and boards have been to provide wiring interconnection capacity, and a robust mechanical structure for the more delicate and costly chips and modules. The advent of surface mount technology eliminated the need for plated‐through holes as anchors for pinned components. The proliferation of light, high performance, multifunction electronic products will lead to light weight, small, low profile printed circuit assemblies. Adding a redistribution layer to the traditional card surface allows flip‐chip‐on‐board and MCM‐L packages as a low‐cost alternative to traditional high density MCM packages, particularly in applications where size, shape and weight are as important as density and performance. Concurrent with the deliberate evolution of traditional printed circuit technology, some important new materials and process innovations have brought about a new generation of laminate capabilities that are particularly important for the future high I/O requirements predicted for the second part of this decade.

This paper examines the size, scope and electronic equipment end‐market ‘drivers’ of the world printed circuit industry. Topics include general industry trends, the captive/merchant producer balance, semiconductors as they relate to PCB demand, regional comments on the European, Americas and Asia/Pacific markets, process consumable consumption and a detailed discussion of the relationship of electronic equipment to PCB demand.

Surface Mounting is shown to be the fourth generation of electronic interconnection technology. It has several facets and is seen differently from various viewpoints in the assembly industry. A review of published papers shows that the subject grew during the 1970s with no single inventor and as a result of numerous developments which are now combining into a coherent technology with important compatibility with other recent innovations.

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 evolution of IC manufacturing technology has led to a decrease in feature size on the silicon die from around 2μm nowadays down to 0.18μm, and in the near future down to 0.13μm. This implies a simultaneous decrease in the distance of the individual contact pads (pitch), decreasing from a moderate 0.5mm to nowadays 0.1mm or even 0.07mm for leading edge ICs. The near future will not allow this trend to continue. Instead of peripheral contacts, several rows of contacts or even use of the entire die area to accommodate the contacts will allow the numbers of IOs to increase to the required value. Following the roadmap of electronic devices the PCB has its design continuously changed. Accordingly we need today PCBs with high density interconnects, realized by sequential build‐up technology (SBU) including microvias. We see at the end of the next decade that the semiconductor technology will be introduced at the PCB level. At this time we are also able to transfer the chip design into the PCB directly. This dependence of the development from chip‐ and PCB‐technology is the subject of the paper.

The approach to reduce the costs of electronic circuits will be the transition of LSI‐circuits to VLSI‐circuits, introducing another order of magnitude to the complexity and density of these circuits. The influence of this will be similar to the transition of discrete transistors to integrated circuits. VLSI‐circuits are, in general, digital circuits and therefore the passive components used in analogue circuits will be used in smaller quantities, just as the discrete transistors will change from small signal to power. Sensors and display units as liquid crystals will gain importance and need to be interconnected in an economic way. Competing with printed circuit boards are hybrid circuits, but these have not yet found general application due to the high innovation rate of integrated circuits. However, special applications as high frequency circuits are cost effective. A cost breakdown of electronic equipment shows that due to the introduction of LSI and VLSI circuits the relative costs of PCB's are rather high and that economics will force the introduction of new technolgies to achieve the correct cost balance.

The increase in semiconductor integration level has led to complex Integrated Circuits (ICs) characterised by an increasing number of I/O, such that dies with 40 to 84 metallised pads are currently manufactured and frequently used in modern electronic systems. The advent from 1980 onwards of these LSI‐VLSI semiconductors requires new economical micropackages to be devised that can be adapted to surface mounting techniques on Hybrid Integrated Circuits (HICs) and Printed Circuits Boards (PCBs). Plastic encapsulation using a transfer moulded epoxy resin is a widely used method for packaging silicon devices because of the reduced manufacturing cost for large volumes. This economic criterion, which is considered with widespread interest in the electronics industry, has recently led the major semiconductor manufacturers to produce Plastic Leaded Chip Carriers (PLCCs) with up to 84 J bend connections on 1·27 mm pitch, and Mini Quad Packs with 40 to 84 Z bend pins on 0·75∼0·80mm centres. However, until now, a significant number of ICs, such as full custom circuits, are not yet available in any packaged form. Thus, in order to take advantage of the compactness offered by micropackages without being under component manufacturers' constraints for packaged LSI needs, it was decided at the Microelectronics Division of CIT‐Alcatel to develop a flexible semiconductor encapsulation technology which does not require any moulding equipment. The process involved has led to the development of a small economical package with 52 peripheral Z bend leads on 0·75 mm centres which has been evaluated. This original LSI carrier, named Plastic Composite Package (PCP) because of its special feature, is perfectly suited to the specific needs of multilayer HICs for all non‐military applications. In addition, another PCP format with 68 pins on 0·635 mm centres, designed for LSI Industrial applications, has been investigated. The purpose of this paper is to explain the specific needs in the hybrid industry and to give the authors' views on trends in LSI‐VLSI plastic encapsulation. Moreover, the PCP manufacturing process is described, the evaluation results being discussed as well as the economic aspect.

A general introduction is given to surface mounted devices, processes and machinery, followed by Mullard Electronic Assemblies Division's experience and a description of practical assemblies using surface mounted devices. Thoughts of future possibilities and requirements of substrate systems for the advancement of surface mounted assemblies are also presented.