Solid Circuits Are The Ultimate Says GWA Dummer

This is what Mr. G. W. A. Dummer (pictured), Superintendent, Technical Services Department, Royal Radar Establishment, stressed in the third of the Ultra 25th Anniversary Lectures presented before a large gathering at the Royal Festival Hall in London last week. His subject was “The Changing Role of Electronic Components”.

So, 66 years ago, started a story in Electronics Weekly’s edition of October 19, 1960

The story continued:

Mr. Dummer stressed that a great deal of research still requires to be done, but eventually it may well be possible to produce solid semiconductor circuits with a life expectancy of over 100 years.

Since the voltage and current ratings will be low, and therefore the heat dissipation small, it should be possible to ensure an extremely high degree of reli-ability.

When considering the evolution of miniature components Mr. Dummer said that it is necessary to take into account the following factors:

the effect of constructional techniques;

the effect of war conditions;

the effect of reliability requirements:

the effect of the transistor;

the effect of microminiaturisation

One of the more immediate answers to the reliability problem, particularly as it applies to aircraft and guided missile elec-tronics, is the use of liquid cooling techniques. Some advanced work on such systems is being undertaken at RRE, and the results are very promising.

Microminiaturisation, Mr. Dummer went on to say, can be achieved in a number of ways.

The micromodule technique. pioneered by RCA in the USA, offers packing densities of 50,000 parts per cu. in. Pre-testing before assembly is a great advantage, but interconnection between assemblies remains a difficult problem.

RRE saw little point in duplicating American work. Instead they have tended to concentrate on flat-plate circuits using evaporation techniques.

Resistors can be made by evaporated dielectrics, and it would be extremely elegant eventually to evaporate complete circuits.

But before this can be effectively achieved, Mr. Dummer concluded, more must be known about the fundamental mechanism of adhesion.