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The aim of this paper is to present a new and original method for on‐chip measurements of very high frequency parasitic signals where a sampling circuit is directly included in the test chip. The paper describes the usefulness of this sensor for measuring signal propagation and cross‐talk glitch on integrated circuit interconnects and also gives the results obtained experimentally.

Presents a survey of build‐up technologies based on the manufacture of microvia in thin dielectric sheets (< 100µm) deposited on PWB materials. These technologies will permit the PWB industry to manufacture high density interconnect substrates and answer the routeing requirements of high number I/Os, BGAs and new area array components. Bull Electronics Angers (BEA) has developed an HDI technology where microvias with hole diameters lower than 100µm are mechanically or laser drilled and interconnected lines at pitch down to 200µm are manufactured. In the frame of a European MEDEA project, ATEMAES, the design of an electronic subsystem manufactured by Magnetti Marelli in ceramic thick film technology has been adapted to the design rules of the HDI technology developed by Bull. This is part of an evaluation program for the use of HDI technology for automotive applications.

This paper acts as an introduction to the work of the Microelectronics Technology Centre of British Aerospace at Hatfield. It concentrates, primarily, on the development of a Copper‐On‐Ceramic Technology. The philosophy of using BS 9450 principles to achieve a mature, fully documented process is outlined.

Screen printing for the fabrication of Thick Film microelectronic circuits is now a mature technology. A greater understanding of the processes and materials used has allowed the once ‘black art’ to develop into the high precision, high yield process of today—with circuits containing 250 µm conductors on many levels being printed over large areas up to 6 in. × 8 in. However, electronic systems designers are demanding more compact interconnections and screen printing technology must advance to meet this challenge. Encouraging research to date has demonstrated that 50 µm lines and spaces are readily printable under controlled conditions, and a complete 120 µm multilayer system is now a reality. Unfortunately, this rapid advance in the technology is likely to hit insurmountable barriers in the near future, and alternative patterning techniques may be required if Thick Film technology is to cope with the ultra high tracking densities that will soon be required.

To investigate the influences of environmental stresses on board‐embedded polymeric waveguides.

Optical multimode waveguides were embedded on printed circuit boards using commercial polymers. The optical‐PCBs varying in board structure and in optical build‐up materials were exposed to heat, moisture and ionic‐contaminants in accelerated reliability tests. The influence of stress factors on the structural integrity and functional parameters, namely the refractive index and optical transmissivity, was investigated at the key communication wavelengths.

Isothermal annealing reduced the refractive index to the greatest extent. The optical‐PCB structure with an optical surface build‐up layer was observed to be more vulnerable under temperature shock when compared with the optical‐PCB with optical inner layer. The buffer layer beneath the optical build‐up was found to improve the stability of the optical waveguides significantly. The results indicated of wavelength dependence to the aging factor with a failure mechanism. The factors affecting the performance and reliability of polymer‐based optical waveguides on PCBs were discussed.

More experimental data and investigations of failure mechanisms are required to ultimately obtain sufficient reliability statistics for accurate life‐time prediction models.

Optical interconnects are seen as a promising solution to overcome performance limitations encountered with high‐frequency electrical interconnections. As an emerging technology, only a limited amount of reliability data on optical/electrical packages is available. The paper investigates the influences of environmental stresses on board‐embedded polymeric waveguides.

The ever‐increasing miniaturization and integration of additional functions in the electronics industry – in particular in the next generation telecomm technologies – needs a paradigm shift in manufacturing technologies in order to achieve the results along the roadmaps of the industry. Handling of thin substrates, doing finest line circuitry, working on non‐flat surfaces and having to protect metallized holes during etching processes, are asking for conformal resist coatings. Electrophoretically deposited positive working photo resists encompass these requirements. The principles of electrophoretic photo resists, the necessary equipment, the cooperation between customer, the supplier of process chemistry and the supplier of the equipment to start such a complex project, and start‐up results of the new major production line for ED‐resist in Europe are discussed.

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:

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.’

Rapid advances in silicon, including ever higher complexity and easier access to customised approaches, are forcing dramatic changes in electronic equipment design and manufacture. This paper examines the developing role for hybrid microcircuits and concludes that hybrid technology, often thought of as optional, should now be regarded as an essential partner for monolithic silicon technology.

Passive components integrated into a high‐density substrate can be a tolerable way to overcome the size and manufacturing limits of SMD passives mounted on to the system board. Still, this technology is perceived as being “too risky” and not cost‐effective. In this paper we propose a “passive optimized” solution combining the advantages from both SMD and integrated technology and avoiding the respective drawbacks. Exemplified by a GPS receiver front end, we present a methodology to assess the possible benefits when using the mixed technology.