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A study was undertaken to evaluate the thermosonic gold‐wire bonding capability to Ti‐Pd‐Cu‐Ni‐Au thin film metallisation on newly developed polymer hybrid integrated circuits (POLYHICs). (The POLYHIC technology incorporates alternating layers of polymer and metal added to conventional Hybrid Integrated Circuits which provide for increased interconnection density.) Destructive wire‐pull strengths were measured as a function of varying wire‐bonding machine operating parameters of wedge bond force, wedge bond time, temperature, and ultrasonic energy. All data were evaluated and compared with wire bonding under similar conditions to thin film circuits on Al2O3 ceramic. The results for wedge‐bond associated failures indicated that machine operating parameters of wedge bond force, time and ultrasonic energy similarly affected the average wire‐pull strength for both the ceramic and POLYHIC circuits. Pull strengths for equivalent metallisation schemes and bonding parameters were generally slightly higher and more tightly distributed for bonds made to metal films on ceramic. A strong correlation was found to exist between wire‐pull strengths and surface topography (as measured by a profilometer technique) of the thin film metallisation for the POLYHICs which had both smooth and rough metallisation surfaces for metal films on top of the polymer. The results indicated that rough metallisation bonded more easily and yielded much higher wire‐pull strengths. Also, rougher films were shown to effectively increase the parameter‐operating windows for producing reliable wire bonds. A semi‐quantitative analysis was developed to help explain this correlation. Surface topography effects were also found to be a key factor when evaluating wire bondability as a function of substrate bonding temperature. Wedge‐bond strength was essentially independent of temperature for bonds made to rougher metallisation while a strong temperature dependency was found when wire bonds were made to smoother films.

In this contribution a linear thermal model for hybrid circuits is presented. Both the heat dissipated in screen printed resistors and in mounted components such as transistors and integrated circuits is taken into account.

A recent meeting involved co‐operation with the organisers of the Canadian High Technology Show and the local Chapter of the SMTA. The programme included an inspiring keynote address by Mr Frank J. Pipp, Xerox Corporation. The topic of the address was ‘Malcolm Baldridge National Quality Control and the Evaluation of Total Quality Control in Xerox Corporation.’

High‐performance active RC‐filters realised as a thick or thin‐film hybrid integrated circuit present special fabrication problems. Due to manufacturing tolerances of the circuit elements a vast majority of the filter circuits will probably not meet the performance specifications. As a consequence, the filter networks must be tuned after fabrication. In this paper, two recent algorithms amenable to computer automated functional tuning are reviewed. The algorithms formulate the tuning problem as an optimisation problem which is solved for the tuning amounts required. Then the tuning resistors are adjusted by that amount. The tuning algorithms are tested by examining their performance in tuning an active RC‐filter.

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is presented. Emphasis is placed on a new understanding of the key elements (for example, tapes, bumps, inner lead bonding, testing and burn‐in on tape‐with‐chip, encapsulation, outer lead bonding, thermal management, reliability and rework) of this rapidly moving technology.

The ISHM CAN‐AM Chapter recently organised a half‐day programme of paper presentations followed by a tour of a local hybrid facility. The event took place on 26 April at the Holiday Inn, Montreal (Pointe Claire), Quebec, with the theme of the papers concentrating on advances in hybrid manufacturing processes and some coverage of SMT.

On 20 April ISHM‐Benelux held its 1988 Spring meeting at the Grand Hotel Heerlen. This meeting was totally devoted to implantable devices, in particular to the technologies used for these high reliability, extremely demanding devices. For this meeting ISHM‐Benelux was the guest of the Kerkrade facility of Medtronic. Medtronic (headquartered in Minneapolis, USA) is the world's leading manufacturer of implantable electronic devices. Apart from the assembly of pacemakers and heart‐wires, the Kerkrade facility acts as a manufacturing technology centre for Medtronic's European facilities.

Testing has become one of the dominant costs in the process of bringing a product from initial conception to the market place. Because of this, it is now imperative that the impact of any technology change on the test process is considered at an early stage. In this light, the increasing trend towards the use of surface‐mounting techniques in the fabrication of electronic systems is examined, with particular emphasis on the consequences on product testing during design validation, manufacture and repair. The aim is to highlight areas in which new attitudes and replacements for traditional solutions will be needed if surface‐mounting techniques are to be as cost‐effective as possible.

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.

Drive east from Frankfurt, upstream along the valley of the River Main, and in 25 kilometres or so you will reach Hanau, where once the brothers Grimm lived and collected the folklore which we now know as the famous Tales. Here too, in 1856, Wilhelm Carl Heraeus, a chemist and pharmacist, proprietor of the pharmacy which had carried the family name for many generations, succeeded in producing temperatures approaching 2000°C from an oxy‐hydrogen flame, temperatures sufficiently high to achieve the melting point of platinum and to allow him to melt substantial quantities of this metal for the first time. Hanau was then a centre for the jewellery manufacturing industry (and remains so today) so the smelting of platinum and other precious metals had an immediate commercial relevance.