Transistor History

Transistor History

The transistor history tells of a development that took many years. It built on many years of theoretical research into semiconductors.

First semiconductor diodes arrived and these were able to deliver improved performance over thermionic predecessors in some areas.

However the transistor history is a testament to the perseverance of the researchers who were finally rewarded with the first semiconductor amplifying device.

Bardeen, Brattain, and Shockley were the names that are remembered within the transistor history, but there were many others along the way, who also contributed to the final invention of the bipolar transistor.

Transistor history foundations

The first foundations in the transistor history were set in place many years before. Even in the nineteenth century it had been observed that a class of materials had some unusual electrical properties. These semiconductors had a negative coefficient of resistivity, they were able to rectify electrical currents and they exhibited a photoelectric effect.

Another early use of semiconductors was for the "cat's whiskers" which were detectors used in radio sets. Although they were cheap, there were notoriously unreliable.

Although there was comparatively little interest in semiconductors at this stage of the transistor history before the Second World War, but some developments did occur. Copper oxide and selenium rectifiers started to be used, particularly in applications like battery chargers. The photoelectric effect was also exploited in photographic exposure meters. However their use was relatively limited.

However some development of semiconductor devices occurred in the 1920s and 1930s, most of the theoretical research into the sub-molecular physics was directed towards thermionic technology. This was because even small advances in this field would produce large rewards and a handsome return on investment.

Diode developments

One of the major motivators in the history of the transistor and the development of semiconductor technology in general was the Second World War. One of the greatest advantages which Britain held over Germany was the use of Radar. Operating on relatively high frequencies the need for high performance high frequency components became even more acute. Semiconductor technology was a major key to performance at the higher frequencies being used.

Experts in all fields associated with the development of semiconductors from the UK and USA were quickly assembled. Work started on producing point contact diodes.

As the work progressed semiconductor diode technology made many strides forwards. Teams on both sides of the conflict made developments which gave devices which a far superior performance to anything that was available before the war.

Transistor work starts

As hostilities started to draw to a close, Bell Laboratories realised that there were major possibilities for semiconductor technology. In the spring of 1945 a major meeting was called to discuss the future research into them - this was a pivotal point in the transistor history. Later that year authorization was granted for research to proceed to seek "new knowledge that could be used in the development of completely new and improved components".

As a result a solid state physics group was set up under William Shockley and Stanley Morgan. Shockley also headed up the semiconductor sub-group which was to include Brattain and Bardeen to make up the trio who invented the transistor.

Transistor trio

The three main characters involved in the transistor history were:

  • William Shockley: He was born in London in 1910 of American parents. He only remained in England for three years after which his parents returned with him to the U.S.A., settling near San Francisco. Here he gained his first degree from the California Institute of Technology after which he moved to the Massachussetts Institute of Technology to gain his Ph.D. in 1936.

    After leaving University Shockley joined Bell Laboratories, initially working on electron diffraction. In 1955 he moved on from Bell Labs to set up his own company called Shockley Semiconductors in his home town of Palo Alto. This company attracted many other semiconductor experts. With the influx of expertise several other companies started up in the area. One backed by the Fairchild Camera and Instrument Company was started in 1957 by a number of Shockley's old employees. This all had a snowball effect and before long this small area had the highest concentration of semiconductor experts in the U.S.A.. Silicon Valley was born.

  • Walter Brattain: He spent his first few years in China, moving to Washington State when his parents returned home. He took his first degree at Whitman College in Washington State, moving to the University of Minnesota to gain his Ph.D..

    After leaving university Brattain applied to Bell Laboratories but they turned his application down. Instead he went to work for the National Bureau of Standards. Brattain soon applied again to Bell, and at the second attempt he was successful. After joining Bell he initially worked on copper oxide and semiconductor rectifiers, giving him a good grounding in semiconductor technology. Brattain remained at Bell until his retirement in 1967. During his retirement he held the post of Visiting Professor at Whitman College until his death in 1987.

  • John Bardeen: He was the only one of the trio to be born in the U.S.A.. He was born in Wisconsin in May 1908. Taking his first degree at the University of Wisconsin, he moved on to Princeton for his Ph.D.. After taking up a fellowship at Harvard and a teaching post at Minnesota University he joined the solid state physics group at Bell Laboratories in the Autumn of 1945.

    In 1956 he received a Nobel Prize along with Shockley and Brattain for his work on the transistor, but by this time he was involved in research into superconductors. It was in this area that he felt he made his greatest achievements, and in 1972 he was awarded a second Nobel prize for this work.

    In addition to his Nobel Prizes he received a number of other awards, including a gold medal from the Soviet Academy for Science. Bardeen died at the age of 82 at the beginning of February 1991.

With the preparatory work done, and the team assembled, the transistor history moves onto the actual invention of the transistor.

Watch the video: How Does a Transistor Work? (January 2022).