Microelectronics International

Fairbairn, Alan J.; Waterfield, Brian

1983 Microelectronics International

doi: 10.1108/eb044122

We, in the International Society for Hybrid Microelectronics, are reflecting the changes in our industry but we must also brace ourselves to accept the challenges. In our efforts within the Society to become more professional we have in fact initiated many changes and already faced many challenges. The Corporate Membership policy has been one whereby companies involved in all aspects of the hybrid microelectronic industry, suppliers, manufacturers and, of even greater importance, customers can become Corporate Members of ISHM and nominate two individual members to represent their interests. It was hoped that this would encourage more corporate backing for our projects which, if our annual exhibition, Hybrid MicroTech, is any guide, has been very successful. Our Corporate Members have beaten a path to our door in order to exhibit at this new Hybrid Microelectronics event, surely now becoming the premier meeting place for our industry in the UK.

Johnson, K.I.

1983 Microelectronics International

doi: 10.1108/eb044123

The dramatic expansion in the use and capability of electronic devices in recent years has been facilitated by the substantial development of production techniques. Modern electronic circuits as used in the computer, defence, aerospace, vehicle and domestic appliance industries contain a great many joints and these have to be made reliably and economically without degrading sensitive circuit components. This article describes the major microjoining developments currently of interest to the microelectronics industry, with emphasis on the work conducted by the microjoining section of The Welding Institute, much of which has been directly sponsored by the UK Ministry of Defence DCVD.

Green, W.J.

1983 Microelectronics International

doi: 10.1108/eb044124

Polymer thick film, as an additive process for making circuitry, is not new but has recently received considerable attention. The process has a number of attractive features to offer and when radiation curing is used to accelerate the curing process the technology becomes even more attractive. To be accepted by industry on a large scale, however, these materials must be certified by independent circuit board testing laboratories. Using infrared as the curing process, Methode prepared a polymer thick film version of a test pattern used for testing to Mil 55110 and produced some very promising results.

Boswell, D.

1983 Microelectronics International

doi: 10.1108/eb044125

This paper reviews the need for a more realistic and professional approach by UK OEM circuit designers and hybrid engineers to the philosophy and practice of long lifetotal excursiontolerancing. It offers simple methods, including offset calculations, for both thick film resistors and multilayer ceramic chip capacitors X7R, e.g., in BT Class 1 and Class 2 applications. Acceptance of these principles enables improved product life for the same initial setting selection tolerance and width.

Simon, J.

1983 Microelectronics International

doi: 10.1108/eb044126

For several years, competition within the resistor network industry has greatly increased sizeable increases in demand. To remain competitive and a leader in the field, CTS Corporation has chosen to initiate constantly new technologies for automation. To improve overall costs, automation must take place in the area of support personnel such as clerks, engineers, management and technicians as well as with the direct production workers. It is also believed that automation should take place under a well formulated planning system. Some of the techniques being implemented at CTS of Berne to accomplish this come under discussion. First, the capability of the process should be proven. Dealt with briefly are ways in which this is accomplished and the important role it plays in the forerunning steps of automating. Before an automation project is undertaken, the payback to the company must be assured. The steps taken to accomplish this, starting with determining the variance in output rates not cycle rates, yield andor quality improvements, acquiring quotations, establishing total costs, and finally computing the ROI and payback factors are all reviewed. CTS Corporation has graduated from high labour intensified manual operations to semi and fully automatic ones. Some of the techniques used to effect this transition such as bowl and vibratory feeders, walking beams, and pickandplace units, are discussed. Also portrayed is the way in which a constant improvement in the automation of the process and material handling is being undertaken at CTS. Among the new generation developments are Multiple handling of parts via tubes, magazines, and pallets robotics automatic 100 visual inspection, and computer and microprocessor controlled processes.

Hargrave, C.E.

1983 Microelectronics International

doi: 10.1108/eb044127

Basic properties of screen materials are defined, with a study of different mesh formations and coatings and their effect on the printed image. Detailed specifications are given for a range of stainless steel, polyester, and nylon fabrics. A table then summarises recommendations for specific thick film applications such as conductor tracks, fine line conductor tracks, resistors, solder paste deposition, dielectric layers, and overglazes. The requirements for the artwork and photopositive are examined, with recommended procedures for exposing and processing the mask. The survey concludes with notes on other factors which commonly influence quality at the print stage.

Hauschild, F.D.

1983 Microelectronics International

doi: 10.1108/eb044128

In the manufacture of resistors with low TCR values it is found that difficulties start at TCR values of less than 50 ppmC. This paper will show if 50 ppmC is a realistic value for high volume production.

Hazzard, H.

1983 Microelectronics International

doi: 10.1108/eb044129

This paper introduces and describes a new concept in multilayer ceramic capacitor MLC design which dramatically improves final microcircuit packaging density by incorporating buried capacitors in a multilayer ceramic interconnection substrate. This substrate, which is not conventional 94 alumina but a high K replacement, is compatible with conventional air firing thick film conductive, dielectric, and restrictive materials. Included is a discussion of substrate characteristics and potential custom thick film multilayer interconnections.

Molyneux Child, J.W.

1983 Microelectronics International

doi: 10.1108/eb044130

The escalating problem of electrostatic discharge damage to MOS devices, resulting from the need for a continual reduction in chip geometry, is examined, with data provided on the range of ESD susceptibility for various component families. It will clearly be of benefit to implement measures that will offer longterm protection against device degradation.

Silver, N.

1983 Microelectronics International

doi: 10.1108/eb044131

As semicustom devices increase in complexity, much time is being devoted to solving the problems of automating their design. The associated problems of packaging are being overlooked. The increasing pin count is becoming a major problem. Surface mount components and hybrid circuits are proposed as a solution.

Val, C.; Humbert, N.

1983 Microelectronics International

doi: 10.1108/eb044132

Previous studies on special dielectrics for multilayer screen printing led to defining a new concept for standard alumina substrate. The modification of the process and structure permits an increase of the thermal conductivity. The thermal conductivity of this new material is between that of alumina and BeO. It is possible to increase the thermal conductivity of 94 standard alumina used in chipcarriers up to 36 times. It it known that the thermal conductivity of beryllia is 7 times higher than that of alumina. The thermal model gives an increase of 4 times for other configurations nontested in this study. With this material, the other characteristics such as thermal expansion, adhesion of the conductors, etc., scarcely change. The percolation effect of the physical properties can usually be found with the addition of another material inside the matrix. In this particular case, the material is not submitted to the percolation law. Different configurations of metallic insert alumina with beryllia are compared by a simulation programme. The main applications are in the field of electronic packaging such as chipcarriers with higher thermal dissipation and substrates for power devices. Since the process used to produce this new material is based on standard operations well known by alumina manufacturers, the cost is potentially much lower than for BeO.

Waterfield, Brian

1983 Microelectronics International

doi: 10.1108/eb044133

The CITAlcatel Group, with a turnover of more than 10 billion French francs, is a subsidiary of the huge Compagnie Gnrale d'Electricit and is deeply involved in the telecommunications industry. It is particularly known for its experience in digital techniques. 6000 of its 40,000 workforce are employed abroad, and with an increasing number of turnkey telecommunication systems installed in so many countries they will undoubtedly have a large share of the messagehandling and office automation markets in addition to direct speech business. Their E10, timedivision switching system ordered by 30 countries, alone represents 105 million subscriber lines to 1982.

Waterfield, Brian; Moran, Peter; Sinnadurai, Nihal

1983 Microelectronics International

doi: 10.1108/eb044134

ISHM UK presented a technical meeting on this topic on the 23rd October 1982 at the Cunard International Hotel, London. The meeting was attended by some 50 engineers, both those involved in the field of hybrids and potential users. It was generally felt that this was a useful meeting but more especially that it would have appealed to many potential users of hybrids, had the right people been able to be contacted.

Gross, Dennis; Waterfield, Brian

1983 Microelectronics International

doi: 10.1108/eb044135

As a result of reorganisation within the Company, AVX Limited have appointed Keith France as General Manager, Sales and Marketing. Previously General Manager, Sales, Europe, Mr France now assumes the added responsibility for the marketing of AVX products throughout Europe.

1983 Microelectronics International

doi: 10.1108/eb044136

An improved quality NQ3 of coated substrates for the manufacture of thin film hybrid circuits is now available from Balzers.