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The Discovery of Transistor
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2007-9-13
The discovery of transistor represents a remarkable milestone in the history of physics development in the 20th century. Leveraged by this discovery for the past half century, we entered into the micro-electronics age and met with great innovation on information industry which brought great changes to people¡¯s production and living and social productivity.
As earlier as in the beginning of last century, people learned the rules of electron's motion in vacuum and discovered vacuum triode (vacuum tube) and opened a new area of electronic technology. However, vacuum triode has a very low utilization efficiency rather than an ideal object due to its overheated filament and short lifecycle especially when it is used for processing HF signals; therefore, scientists have never stop looking for a new material to make up the defects of vacuum tube. When a group of scientists from Bell Telephone Laboratories of AT&T Corporation were looking for a better demodulation material, they found that germnium crystal material with very few inclusion of foreign substance had a better rectification performance than electronic tube. Fortunately, some scientist made progress during this period in their theoretical research on germanium and silicon, which gave further conditions for the discovery of transistor. In the Autumn of 1945, USA Bell Telephone Laboratories established a semiconductor research group under the leadership of William Bradford Shockley who jointed Bell Telephone Laboratories in 1936 with participation of other scientists including John Bardeen and John Bardeen. In 1946, Bell Semiconductor Group made its decision to concentrate on two kinds of the simplest semi conducting material germanium and silicon; based on repeated experiments, John Bardeen and John Bardeen made a solid unit. They used two whisker contacts which were the closest to each other with a space of 0.05mm to replace gold foil contacts and fabricated ¡°contact type transistor¡±. This experiment found that transistor was able to amplify electric current. In 1947, the world first applied transistor came into birth. In the first experiment, transistor was able to amplify signal 100 times, and the amplified signal had an appearance bigger and shorter than a match stick.
For caution purpose, the transistor inventors suspended their declaration of their discovery of transistor. This suspension is normally practical for two reasons: one is there need more verifications by colleagues on a inventions and shall be reported to concerned scientists; another is there are issues relating to patent application and confidentiality. Due to such reasons, this invention was officially patented in USA on June 17, 1948 and declared in Bell Telephone Laboratories' Meeting Hall on July 22 to the scientists who were working there. On July 25, John Bardeen and John Bardeen drafted two letters to the editors of "Physics Journal": "Transistor, a kind of semiconducting triode" and "The nature of forward current in germanium contact"; soon after, William Bradford Shockley and G. L. Pearson also published their papers. These letters were published in "Physics Journal 74" published on July 15 to make the whole world get to know the discovery of transistor.
The discovery was one of most significant inventions in the 20th century. It is the first signs of micro-electronic revolution and the irreplaceable impetus to drive the further development of electronic computer. Also for this remarkable invention, John Bardeen, Walter Houser Brattain and William Bradford Shockley shared the Nobel Prize in Physics in 1956.
Now, the common transistor has two types - bipolar transistor and field effect transistor; they are both the critical components of electronic computer. Bipolar transistor is the basic unit of computer CPU, while field effect transistor is the basic unit of computer memory unit.
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Organizer:
Beijing Municipal Association for Science & Technology
Undertaker: Beijing Science & Technology
Consulting Center,
Information Center of Beijing Municipal Association for
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