II. Glimpses of history development of the transistor

Until 1940, developments in electronics took place at a compar­atively slow pace. As was true with many scientific and techno­logical matters,² the pace quickened during World War Two. Two major developments occurred in the late 1940s. One was the construction of programmable electronic computers. The second was the invention of the transistor.

In the summer of 1945 in the Bell Laboratories in the United States, a group of very able scientists started work wrth the aim of producing devices useful in telecommunications. They were searching for switches to replace mechanical relays in telephone exchanges and amplifiers to replace the bulky and energy-consuming valves. The first fruit of their labours was announced to the world in June 1948. This was the point contact transistor. The device consisted of a small piece of crystalline germanium with two closely spaced wire contacts made on one of its surfaces. The voltage across one of these contacts, that is the voltage between the germanium base and one wire (a first pair of terminals) influenced the current which flowed between the base and the' other contact (second pair of terminals). The reason for this influence is the injection or extraction of carriers of electricity— negatives, electrons ('^"-carriers) or positives, "holes" ("p"-carriers) from the vicinity of contact, thus modifying the conduc-tiyity in that region. If the voltage between the first pair &f terminals of a device causes a change of current between a second pair of terminals, then we have an amplifier. The point contact transistor is rather like two point contact rectifiers, which are in very

it was cheaper to let a... computer keep track of inventory... than to have... clerks trying to do the same thing by hand — дешевле проводить переучет... с помощью ЭВМ, чем держать,-, служащих, которые будут делать то же самое нручную

As was true with many scientific and technological matters—Как это проис­ходило со многими направлениями науки и техники

close proximity, but the result is the long-dreamed-of crystal

amplifier.

By the time' the first applications of this invention became available, its successor device has already been announced bv Bell Laboratories—the junction transistor, a low-power amplifier which replaced the large power-hungry vacuum tube. The transistor soon became typical of the semiconductor industry.

The junction transistor was also made of a germanium crystal, though this was mostly replaced later by more cheap silicon. The crystal had three electrically different layers in which the cur­rent was carried by different charge carriers. The crystal was a kind of sandwich with the two outer, and thicker, layers consisting of a material of one ("n") conductivity and the middle, the thin base of another ("p") conductivity. The current in the outer layers was carried by electrons, negative charge carriers, and the current in the base was carried by "holes", .positive charge carriers. The device came to be called² n-p-n. Three of the engineers of the Bell Laboratories group have become world-known names: Bardeen, Brattain and Shockley.

It is noteworthy that as early as³ in 1926 the Russian radio engineer Oleg Losev of Nizhny Novgorod (now Gorky) built the first semiconductor amplifier crystal-based device. He catted it "Crystadin". However, at that time solid-state physics was not yet developed enough and Losev's work was shelved.