Pocket Television Set

Press, Volume CIX, Issue 32050, 26 July 1969, Page 5

Pocket Television Set

A small metal box, no larger than a box of matches, stood on the desk of the president of a major American electronics firm during the last World Series baseball tournament.

It was not a matchbox but a television set. The definition of its two-inch wide screen was astonishingly clear, and the sound from its half-inch loudspeaker strong enough to carry across the room.

The miniaturised marvel, which gave the president a grandstand view of all the major games in the series, was, in fact, the prototype of something we could all be carrying in our pockets within the next five years or so. It will be made possible by the introduction of an

astonishing new electronic technique which, it is expected, will eventually oust the transistor as the world’s most popular power-pack. There is no reason, say the experts, why in a few years’ time, we should not be operating computers the size of 20 cigarettes, or listening to radio sets no larger than a lump of sugar.

White Elephant And TV sets no larger than a matchbox will be slipped into the pocket for “instant viewing” in the train going home. The secret behind this super-miniaturisation is a tiny circuit which disposes of all conventional power sources and circuitry. It could even make the present tiny printed circuit a white elephant of electronics. Now after four years development, a new and quite incredible breakthrough is in process of making the transistor as clumsy and old-fash-ioned as the glass valve. An astonishing technique, called micro electronics, enables complete circuits to be made so small that several hundred could be fitted on to a single match-head. New Generation Strangely, what prompted the research and development work into such tiny circuits was not a desire to shrink the size of electronic equipment for the sake of it, but to improve its reliability and speed of operation.

Obviously, the faster a computer works, the more use it is. Valves and complicated wire connections slow things down, consume an enormous amount of power and run the risk of breakdown.

Transistors are better, but the circuits are still huge and inefficient when compared with the equivalent in microelectronics.

To step inside one of the new generation of microelectronic factories is to enter a strange and sterile world. The smallest speck of dust could ruin a circuit, and the air in the construction areas must be cleaned so that there are no more than 1000 specks of dust per cubic foot of air -

Temperature and humidity, too, are carefully controlled, and all visitors and workers must pass through an airlock and put on special protective clothing. To construct a micro-cir-cuit, development engineers first build up the required circuit using conventional electronic parts, transistors, coils and so on. Then this is converted into a circuit design and detailed calculations made as to what snags, if any, will emerge when the circuit is miniaturised.

A plastic “mask” is then cut of a single micro-circuit, which is then photographed on a special camera, that reduces the .circuit to the re-

quired size and repeats the design hundreds of times over on the photographic plate. The photographic images are then transferred to specially coated dises of silicon. The finished product is a piece of silicon bearing an exact reproduction of the original mask, reduced to pinhead size and repeated hundreds of times. Next, the plate, containing the hundreds of circuits, is scored with a fine diamond point to separate each one.

These must now be mounted inside a protective capsule and fine gold wires connected to the correct points of the circuit. This precise and exhausting work is done by women and girls—men, apparently, lack the necessary patience—using binocular microscopes and ultra-sensitive pointers and probes. Reduction gears inside the equipment ensure that a movement of a few centimeters, made by the operator, will only move the instruments a few thousands of a centimeter at the circuit face. Pin-head Gold wire, finer than spider’s silk, is fixed to the circuit by high-frequency sound waves. Finally, the finished product—so small you could easily push it under your thumb-nail is checked thoroughly by a computer. It has to be: the circuit is as complicated as your transistor radio or television set. The only difference is that it has been shrunk to the size of a pin-head. Most of the millions of circuits now turned out each year end up in computers. Until recently, a computer built from orthodox valves might have needed as much space as a small house. Transistors reduced that size to the equivalent of one room in the house. Now, micro-electronics would fit the same computer into the space needed by a cocktail cabinet. —Copyright, Provincial Press Features.