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Light radiation cure adhesives, coatings and encapsulants are being used in the electronics manufacturing industry with increasing frequency because their properties and process advantages are a good fit for the manufacturing requirements which are demanded by current industry drivers, such as miniaturisation, environmental and health & safety demands, manufacturing yield improvement and total product cost. Light curing adhesive systems in the electronics manufacturing industry have found applications in strain relief, wire and parts tacking, coil terminating, tamper‐proofing, structural bonding, temporary masking, potting, encapsulation, glob topping, conformal coating, and surface mount component attachment. This paper describes three case histories where photo cure adhesives were introduced to an electronics manufacturing environment, and discusses their rationale, implementation and their economics. The case histories encompass printed circuit board assembly (including surface mount), electronics packaging and microelectronic encapsulation. Production managers and process engineers are given confidence that practical adhesive application can be clean, fast and economical.

The purpose of this paper is to report on various adhesives and their uses in the electronics industry.

A description of the different types of adhesives and their strengths and weaknesses is followed by illustrations of their applications in electronic and electrical assembly. Equipment and procedures for cleaning and surface preparation are presented, and the paper finishes with an examination of techniques for rework and repair.

Polymers form the body of an adhesive, but other elements may be included to control electrical and heat conduction, light absorption and cross‐bonding behaviour. This makes them highly controllable and adaptable to specialised requirements. Photo‐curable adhesives with cure times of under 1 s are available for fast‐throughput assembly. Polymer underfills are increasingly important for shock‐proofing handheld electronics. Adhesives and cleaning agents are becoming environmentally safer.

The paper reveals the versatility of polymer adhesives and names suppliers.

The last decade witnessed the increasing use of Surface Mount Technology (SMT) in the assembly of Printed Circuit Boards (PCBs). This fact coupled with increasing component densities, decreasing component pitch, and the need for reliable PCBs has focused attention on the critical components of the manufacturing process including the adhesive used. Components used in PCBs manufactured using SMT, which are to be wave soldered, must be adhesively attached to the board so that they remain in place during the wave soldering process. Utilisation of non‐conducting adhesives for the attachment of electronic components prior to wave soldering has become common throughout the electronics manufacturing industry. The knowledge based adhesive selection adviser described in this paper assists the user (process engineer) in the selection of adhesives for wave soldering of surface mount components. In addition to guiding the user through the adhesive selection process, it provides dispenser related information. This ‘advice’ is derived from the restrictions imposed by the user (including the user's facility temperature), material property requirements, productivity measures and the adhesive dispensing method. The adhesive selection adviser helps the user understand the relationships that need to be considered during adhesive selection. It is applicable to any existing SMT line that uses adhesives within the commercial PCB manufacturing domain.

Alpha Metals, supplier of solders and solder related chemicals, has promoted Mr Stan Renals to the position of Sales and Marketing Manager, reporting to the General Manager. Having been with the company for some five years, originally as Southern Regional Sales Manager and latterly in the position of National Field Sales Manager, Mr Renals will take on the additional responsibilities of internal sales, marketing and export sales.

The International Society for Hybrid Microelectronics invites the submission of technical papers for presentation at the above event. All original unpublished papers on microelectronics related topics are welcomed.

With the increased functional density requirements of military avionics it is impossible to meet these demands without utilising Surface Mount Technology. The Electronics Manufacturing Technology Group at Boeing Military Airplanes is working to meet SMT design requirements through research and development of processes, materials and equipment for all variations of SMT. Basic processes have been established for both 100% SMT and mixed technology. However, the Group continues to advance its capabilities by evaluating and improving all aspects of SMT manufacturing. A description of the initial thrust into Type III SMT as well as subsequent development is given. This includes a description of the evaluation of Surface Mount Component (SMC) attach adhesives comparing the adhesive used initially with others available by examining the various criteria involved in selecting the appropriate one for a given process. Also, a discussion follows of factors involved in determination of Mil‐spec. passive SMCs which are compatible with wave soldering. Included in the evaluation of passive SMCs is a comparison of the compatibility of the wave solder system in use with the component industry's recommended temperature profiles through an analysis based on in‐house testing to determine the actual component endurance to solder system heating. Throughout this discussion emphasis is placed on a systematic guided approach to examining process development.

LeaRonal (UK) plc of Buxton, Derbyshire, specialists in plating and allied services to the printed circuit board industry, has appointed John Flynn to their technical staff. Mr Flynn, who will be based in his native Scotland, brings with him a decade of experience in electroless copper, hard gold plating and photoimageable processing in the PCB industry.

Electronic packaging is increasingly becoming a vital part of the electronics industry, representing a key barrier to cost reduction and performance improvement. Of all the packaging methods, flip‐chip technology offers, up to now, the highest packaging density and best electrical performance. In this paper, flip‐chip test design considerations, process development and driving forces for adhesive joining and soldering flip‐chip processes will be given. Reliability test results of flip‐chip interconnection technology using conductive adhesive joining will also be presented. The electrical contact nature of the adhesive joint will be elaborated in the light of continuous and static electrical resistance measurement. Future research work directions in flip‐chip joining using eutectic solder and conductive adhesives on flexible circuits will also be discussed.

FRIDAY, December 11, 1992 — While hordes of headline‐seeking journalists at Holyrood Palace competed for the latest scoop on the Edinburgh Summit, it was pleasant to travel west to the calmer setting of Quarriers Village in Renfrewshire. Success was claimed as the outcome of the Summit. Another success story is reflected in the growth and performance of the still fairly young but thriving company Teknek Electronics Ltd. Success in a period of inescapable gloom for the electronics industry is all the more newsworthy. It should also offer a glimmer of optimism to an industry where hope and enthusiasm appear dampened, if not extinguished, by successive recession‐related blows.