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The electronics assembly industry has fortunately rediscovered conductive adhesives as the search for lead‐free joining materials and improved performance intensifies. Although these intrinsically clean bonding agents are often first sought for their favourable environmental attributes, many are surprised to find that conductive adhesives can solve old and new problems. Today, new polymer solders for SMT allow low temperature processing, finer pitch assembly and wider processing latitude while providing compatibility with a very much larger range of materials than solder. State‐of‐the‐art adhesives are oxide‐tolerant and absolutely no fluxing or cleaning is required. Adhesives work where solder cannot be used. What's more, polymer‐based solder alternatives can run on existing SMT lines — no new equipment is needed. Z‐axis, or anisotropic, bonding agents are uni‐directional conductive materials that solve fine pitch interconnect problems in several areas. The anisotropics now dominate the flat panel interconnect field. Nearly every LCD and other flat panel display is connected with a polymer adhesive. The Z‐axis adhesives are also beginning to enable high density multilayer circuits and MCMs to be built more effectively. Finally, Z‐axis appears to offer the simplest and most cost‐effective means for flip chip bonding. However, special equipment is required. The paper compares the metallurgical solder joint, the present de facto standard, with the polymer composite bond to highlight similarities and important differences. All types of conductive adhesives are discussed including the latest — Area Array Z‐axis types. Bonding materials, assembly processes and performance are also covered.

The advantages of incorporating permanent photopolymer (dry film solder mask) coatings into high density printed wiring designs to obtain maximum component density and high reliability are discussed. Although originally developed for use as solder masks, these materials offer significant advantages to the PCB designer. Specific items to be discussed include high density conductor routing, in accordance with the proposed MIL STD 275D, on the solder side and under closely spaced components, component and heat sink mounting, the use of permanent polymer coatings to avoid metallic growth problems, new industry and military specifications and standards that relate to the incorporation of photopolymer masks into PCB designs and effects of coatings on high density, controlled impedance transmission lines.

The purpose of this paper is to present details of the plasma printing and packaging technology (P³T), a new reel‐to‐reel technology under development for the cost and resource efficient manufacture of flexible printed circuits (FPC).

The first two process steps of P³T include reel‐to‐reel patterned activation of polymer film at ambient pressure in the so‐called plasma‐printing process and subsequent selective electroless plating of the plasma‐activated areas of the polymer film. The concept underlying the P³T project includes processing of flexible films with widths up to 400 mm.

Copper, palladium and nickel metal structures with widths down to less than 100 μm were produced on various polymers. Peel strengths according to the German DIN Standard 53494 of copper on polyimide film reached values in the region of 1 N/mm, sufficient for electronic applications. Sufficient wetting of the solder on copper metallisations and solderability were found.

P³T covers the whole manufacturing chain for FPCs from surface patterning of the dielectric carrier to component assembly and soldering. This paper focuses, however, essentially on the first two process steps including plasma activation and electroless plating.

A unique feature of the flexible circuit manufacturing technology presented here is the combination of the additive‐technique, the absence of vacuum processes, the continuous production mode and the ability to process polymer carrier films with widths of 400 mm.

This paper deals with the design of PCBs, using the dielectric properties of solder mask as an insulation layer to protect boards and components; the elimination of selective solder filling of component holes; the protection of via holes during soldering, and the preparation of artwork, with particular attention to design tolerances using dry film solder mask. Future prospects in PCB design, employing dry film solder mask, are also discussed.

The purpose of the paper is to focus on the research into components with specific thermal properties and their influences on the reflow soldering process.

After a brief introduction, the paper gives an overview of the necessity of thermal management on printed circuit boards (PCBs) and the possible effects on the manufacturing of electronic devices. In the next sections, different test boards are presented for investigations into different thermal effects during soldering. The last section deals with the influences of molded interconnected devices (MIDs) on the reflow soldering process.

The investigations show that components from the thermal management influence the reflow soldering process more or less. The highest impacts on the soldering process are from components with a thermal connection to the electrical component and its solder joint. All results from the investigations have in common that the thermal influence can only be compensated by increasing the temperature during soldering. However, this significantly increases the risk of overheating the electrical components or the PCB itself.

This paper shows only the influence of some of the effects caused by thermal management on the reflow soldering process. Furthermore, vapour phase soldering is not considered, but actual investigations are carried out on vapour phase soldering ovens as well.

Thermal management becomes more and more important with the increasing functionality of electrical components and electronic devices. This topic has been the subject of a large number of articles. However, this paper deals with influences that thermal management has on the soldering process during the manufacturing of the electronic device.

Demanding technical requirements of thin film electroluminescent display modules and hard competition in electronic display markets set boundaries for the setting of goals in the development of an extremely thin display module. To meet the targets the problems of electronic packaging concepts had to be considered from the point of view of total optimisation. As a result, a packaging concept was developed which had an influence on all design decisions starting from the end user's requirements and extending to the selection of a special semiconductor manufacturing process. A set of customised high voltage integrated driving circuits was developed. High density interconnection problems were solved by the tape automated bonding of semiconductors and a single‐sided two‐layer polymer thick film circuit board. Throughout the assembly process surface‐mounted components and reflow soldering methods were applied to form a large area printed polymer hybrid module. Viable volume production methods for a flat dot‐matrix display could be suggested.

The International Electronic Components Show in Paris in November, 1983, provided the occasion for a very successful meeting of ISHM‐France which attracted 170 attendees. The following presentations were given:

The Benelux chapter has made a habit of organising meetings with a scientific and commercial accent more or less alternately. This approach has proven to be successful in the past three years. The 1986 Autumn meeting will be another display meeting. A number of papers will be presented by suppliers of materials and equipment for the hybrid and surface mounting industry. In a 300 m2 exhibition room about 25 companies will display their products. The programme of the day leaves ample opportunity for meeting colleagues and suppliers. The meeting will be held in the ‘Jaarbeurs Vergadercentrum’ in Utrecht on 16 October from 9.30–17.00. The annual ISHM‐Benelux general membership meeting will precede the lectures.

This paper aims to detail the qualification of alternative substrate materials and reliability aspects for quad flat no lead (QFN) packages for highly stressed electronic devices, e.g. for use in automotive applications.

Detailed information is given on the advanced climatic and mechanical requirements that electronic devices have to withstand during life cycle testing to qualify for the automotive industry. Studies on the suitability of high‐temperature thermoplastics as substrate materials for printed circuit boards and the qualification of QFN packages for advanced requirements are described. In addition, information on cause‐effect relationships between thermal and vibration testing are given.

With respect to adhesion of metallization on high‐temperature thermoplastics and the long‐term stability of the solder joints, these substrate materials offer potential for use in electronic devices for advanced requirements. In addition, the long‐term stability of the solder joints of QFN packages depends on the design of the landings on the PCB and the separation process of the components during manufacturing.

The paper covers only a selection of possible high‐temperature thermoplastic materials that can be used in electronics production. Also, this paper has a focus on the new packaging type, QFN, in the context of qualification and automotive standards.

The paper details the requirements electronic devices have to meet to be qualified for the automotive industry. Therefore, this contribution has its value in giving information on possible substrate alternatives and the suitability for the usage of QFN components for highly stressed electronic devices.

This year's Internepcon Production Exhibition and Conference (22–24 March 1988, National Exhibition Centre, Birmingham) promises to be the biggest ever in the event's twenty‐one year history and will host a number of special new features.