This, in turn, led to the question: how can a graphical symbol be made to accommodate these new, yet-to-be-developed devices? This also allowed researchers to fabricate devices with extra regions to perform newer functions and we could now envision a day when this device could have multiple regions and/or terminals. RCA and IBM chose initially a different depiction, but this was discontinued after a few years.Ī major process improvement came when the Emitter and Collector were replaced by solid regions, thus avoiding the fragility of wires. Our own books, Principles of Transistor Circuits and Transistor Circuit Engineering, edited by Dick Shea at General Electric (GE), made full use of this symbol. This symbol was universally accepted (after all, Bell Labs had invented the device) and was incorporated into thousands of documents (papers, specification sheets, instruction manuals, books, etc., etc.) all over the world. Over the years, Bell, and many other labs, proceeded to publish a number of papers on this device, including papers on transistor circuits. In either case, the symbol was depicted with a circle around it as an enclosure. These were the symbols for a p-n-p and n-p-n transistor respectively. The complete device was called a p-n-p transistor its graphical symbol depicted an arrow on the emitter, pointed down into the base. The base was doped with impurities so that conduction through it was essentially by electrons, so it was referred to as n-type. Its graphical symbol closely represented this device. Two tungsten wires pressed on its surface, and comprised the Emitter and Collector regions respectively. In its original version, it comprised a slab of semiconductor material, germanium, mounted on a pedestal which served as the Base. This device had three semiconductor regions an Emitter, a Base, and a Collector. The Transistor was invented by Bell Labs in late 1947, and announced to the public in 1948. This paper presents a first-hand description of what happened at this meeting, and how the American system was vindicated by its almost-unanimous acceptance. This comprehensive system was presented for acceptance at the International Standards Meeting in 1961, where an overwhelmingly large number of countries objected to it, and proposed an alternative system as its replacement. This symbol was universally acepted, and expanded over the years into a system which could accommodate new, yet-to-be-developed devices. Bell Laboratories invented the transistor in 1947, and proposed a graphical symbol for its depiction.
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