Student Education Repository (மாணவர்கள் கல்விக் களஞ்சியம்): Today (February 10, 1902) is the birthday of Nobel laureate Walter Houser Brattain, who invented the point-contact transistor.

Wednesday, February 10, 2021

Today (February 10, 1902) is the birthday of Nobel laureate Walter Houser Brattain, who invented the point-contact transistor.

Today (February 10, 1902) is the birthday of Nobel laureate Walter Houser Brattain, who invented the point-contact transistor.

Walter Houser Brattain was born on February 10, 1902, in Among (Xiamen), Fujian, Qing China, to American parents Rose R. Protein and Ottley. Rose R. Brattain was a private school teacher for Chinese boys at Ding-Wen. Ottley Hauser Protein was a talented mathematician. Both are graduates of Whitman College. Ottley and baby Walter returned to the United States in 1903. Rose continued after a while. The family lived for many years in Spokane, Washington. In 1911 he settled near a ranch near Tonasket, Washington. Brattain attended high school in Washington. He attended Queen Anne High School in Seattle for one year, Tonasket High School for two years, and Moran School for Boys on Pinebridge Island for one year.

Brattain later attended Whitman College in Walla, Washington. There he studied with Benjamin H. Brown (physics) and Walter A. Brattain (mathematics). He received his bachelor's degree from Whitman in 1924. He received a double degree in physics and mathematics. Brattain received his master's degree from the University of Oregon in Eugene in 1926 and his PhD from the University of Minnesota in 1929. In Minnesota, Brattain had the opportunity to study a new field of quantum mechanics under John Hasbrook von Wreck. His thesis, supervised by John D. Tate, is the performance of excitation by electron impact and irregular scattering in mercury vapour. Walter Brattain was married twice. His first wife was chemist Karen Gilmore. They were married in 1935. In 1943 William G. Gave birth to a son, Protein. Karen Gilmore Brattain died on April 10, 1957. The following year, Brattain married Mrs Emma Jane (Kirch) Miller, a mother of three.

From 1927 to 1928 Brattain worked at the National Bureau in Washington, DC. There he helped develop piezoelectric frequency standards. In August 1929 he joined Joseph A. Becker at Bell Telephone Labs as a research physicist. Both worked on the heat-induced flow of the charge carriers in the copper oxide rectifier. Protein was able to attend a lecture by Arnold Sommerfeld. Their subsequent experiments on thermionic emission provided test validation for some Sommerfeld theories. They also worked on the surface condition and working function of tungsten and the absorption of thorium atoms. Working on the free surface of a semiconductor was considered by the Nobel Prize Committee to be one of his major contributions to solid-state physics. At the time, the telephone industry relied heavily on the use of vacuum tubes to control electron flow and amplify current. Vacuum pumps are not reliable or efficient.

Bell Labs wanted to develop an alternative technology. In the early 1930s, Brattain worked with William P. Shockley on the idea of a semiconductor amplifier. It used copper oxide. This is an initial and failed attempt to create a domain effect transistor. Other researchers at Bell and elsewhere were experimenting with semiconductors using materials such as germanium and silicon. But pre-war research effort was somewhat hampered and lacked a strong theoretical basis. During World War II, Bratten and Shockley were involved separately in research on magnetic detection of submarines at the University of Columbia with the National Safety Research Team. Brattain's team developed magnetic measurements to detect anomalies in the Earth's magnetic field caused by submarines.

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In 1945, Bell Labs was reorganized and formed a team to do basic research in solid-state physics related to communication technologies. The creation of the subdivision was approved by Vice President Mervyn Kelly. An interim group, which includes Shockley and Stanley O. Connected by Morgan. John Bardeen soon joined the new group. Bardeen was a close friend of Brattain's brother Robert, who introduced John and Walter in the 1930s. Bardeen is a quantum physicist. Shackley is an expert in solid-state physics who is an outstanding experimenter in Breton material science and the leader of their team. According to the theories of the time, Shockley's field-effect transistor was coated with silicon thin silicon and mounted near a metal plate. He ordered Bretton and Bardeen to find out why it was not. Both underwent various tests in November and December. Tried to determine why Shockley's device would not multiply. Bardeen is a brilliant theorist. Bratten, equally importantly, had "an intuitive sense of what you can do with semiconductors". Bardeen theorized that failure to conduct may be the result of local variations on the surface.

Breton and Bardeen were able to push the gold metal dot into the silicon and create a small magnification by circulating it in filtered water. Replacing silicon with germanium improved multiplication. But only for low-frequency currents. On December 16, Bratten devised a method of joining two gold leaf contacts together on a germanium surface. Bratten declared: "Using this double-point contact, 90 volts were anodized on a germanium surface, washed with electrolyte H2O, and some gold spots evaporated on it. The gold contacts were pressed neatly on the bare surface. Also used flat. The phase dependence (DC) must be positive to obtain the multiplication.

According to Bardeen, "Preliminary tests with gold suggested that holes be introduced into the germanium block immediately and that the concentration of holes near the surface is increased. The names of the emitter and collector were chosen to describe this event. After suggesting that electrons were being compensated for and suggested junction transistor geometry, subsequent experiments showed that both Protein and I showed that could occur in point-contact transistors. On December 23, 1947, Walter Bratten, John Bardeen and William B. Shockley first commissioned their colleagues at the Bell Labs. The transistor, which amplifies signals and supports the processing of digital information, has become a "major operator of modern electronics". All three were awarded the 1956 Nobel Prize in Physics for their "research on semiconductors and their discovery of the transistor effect".

The 1947 demonstration was a major breakthrough. Bell Labs is now actively focusing on what is known as the Surface Levels Project. Initially, strict secrecy was observed. The carefully forbidden internal conferences at Bell Labs shared information about the work of Brattain, Bardin, Shockley and others involved in related research. Ralph Bray and Seymour Benser, who studied opposition in German at the University of Burdock, were concerned about whether a similar discovery could be made before Bell Labs. On June 30, 1948, Bell Labs held a press conference to publicize its findings. They also adopted the open policy of freely sharing new knowledge with other organizations. In doing so, they avoided classifying the work as a military secret. And made possible the extensive research and development of transistor technology. Bell Labs has organized several symposia open to university, industry and military participants. They were attended by hundreds of scientists in September 1951, April 1952 and 1956. Representatives of international and domestic organizations attended.

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Bratten emigrated to Seattle in the 1970s. Shockley believed that he should have all the credit for inventing the transistor and that Brattain devoted most of his life to the study of surface electronics. Walter Hawser Bratten, the winner of the Nobel Prize for his invention of the point-transistor transistor, died of Alzheimer's disease on October 13, 1987, in Washington, DC. He was buried in Pomeroy City Cemetery, Washington.

Source By: Wikipedia

Information: Ramesh, Assistant Professor of Physics, Nehru Memorial College, Puthanampatti, Trichy.