Walter Houser Brattain
Encyclopedia
Walter Houser Brattain was an American
physicist at Bell Labs
who, along with John Bardeen
and William Shockley
, invented the transistor
. They shared the 1956 Nobel Prize in Physics
for their invention. He devoted much of his life to research on surface states
.
on February 10, 1902 and spent the early part of his life in Springfield, Oregon
and Tonasket, Washington
in the United States
. He was raised in Tonasket, Washington on a cattle ranch owned by his parents, and earned his B.A. degree in physics and mathematics at Whitman College
in Walla Walla, Washington
. Brattain earned that degree in 1924 and an M.A. degree from the University of Oregon
in 1926. He then moved eastward, taking his Ph.D. degree in physics at the University of Minnesota
in 1929. Brattain's advisor was John T. Tate Sr., and his thesis was on electron impact in mercury vapor. In 1928 and 1929 he worked at the National Bureau of Standards in Washington, D.C.
, and in 1929 was hired by Bell Telephone Laboratories
.
Brattain's concerns at Bell Laboratories in the years before World War II
were first in the surface physics of tungsten
and later in the surfaces of the semiconductors cuprous oxide and silicon. During World War II Brattain devoted his time to developing methods of submarine detection under a contract with the National Defense Research Council at Columbia University
.
division of the newly-organized Solid State Department of the laboratories. William Shockley
was the director of the semiconductor division, and early in 1946 he initiated a general investigation of semiconductors that was intended to produce a practical solid state amplifier
.
Crystals of pure semiconductors (such as silicon
or germanium
) are very poor conductors at ambient temperatures because the energy that an electron must have in order to occupy a conduction energy level is considerably greater than the thermal energy available to an electron in such a crystal. Heating a semiconductor can excite electrons into conduction states, but it is more practical to increase conductivity by adding impurities to the crystal. A crystal may be doped with a small amount of an element having more electrons than the semiconductor, and those excess electrons will be free to move through the crystal; such a crystal is an n-type semiconductor. One may also add to the crystal a small amount of an element having fewer electrons than the semiconductor, and the electron vacancies, or holes, so introduced will be free to move through the crystal like positively-charged electrons; such a doped crystal is a p-type semiconductor.
At the surface of a semiconductor the level of the conduction band can be altered, which will increase or decrease the conductivity of the crystal. Junctions between metals and n-type or p-type semiconductors, or between the two types of semiconductors, have asymmetric conduction properties, and semiconductor junctions can therefore be used to rectify electrical currents. In a rectifier, a voltage bias that produces a current flow in the low-resistance direction is a forward bias, while a bias in the opposite direction is a reverse bias.
Semiconductor rectifiers were familiar devices by the end of World War II, and Shockley hoped to produce a new device that would have a variable resistance and hence could be used as an amplifier. He proposed a design in which an electric field was applied across the thickness of a thin slab of a semiconductor. The conductivity of the semiconductor changed only by a small fraction of the expected amount when the field was applied, which John Bardeen
(another member of Shockley's division) suggested was due to the existence of energy states for electrons on the surface of the semiconductor.
. He moved to Seattle, Washington, in the 1970s where he lived until his death.
episode "Night Terrors," was named after the scientist.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
physicist at Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
who, along with John Bardeen
John Bardeen
John Bardeen was an American physicist and electrical engineer, the only person to have won the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon Neil Cooper and John Robert Schrieffer for a...
and William Shockley
William Shockley
William Bradford Shockley Jr. was an American physicist and inventor. Along with John Bardeen and Walter Houser Brattain, Shockley co-invented the transistor, for which all three were awarded the 1956 Nobel Prize in Physics.Shockley's attempts to commercialize a new transistor design in the 1950s...
, invented the transistor
Transistor
A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...
. They shared the 1956 Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for their invention. He devoted much of his life to research on surface states
Surface states
Surface states are electronic states found at the surface of materials. They are formed due to the sharp transition from solid material that ends with a surface and are found only at the atom layers closest to the surface. The termination of a material with a surface leads to a change of the...
.
Early life and education
He was born to Ross R. Brattain and Ottilie Houser in Amoy, ChinaXiamen
Xiamen , also known as Amoy , is a major city on the southeast coast of the People's Republic of China. It is administered as a sub-provincial city of Fujian province with an area of and population of 3.53 million...
on February 10, 1902 and spent the early part of his life in Springfield, Oregon
Springfield, Oregon
Springfield is a city in Lane County, Oregon, United States. Located in the Southern Willamette Valley, it is within the Eugene-Springfield Metropolitan Statistical Area. Separated from Eugene to the west, mainly by Interstate 5, Springfield is the second-most populous city in the metropolitan area...
and Tonasket, Washington
Tonasket, Washington
Tonasket is a city in Okanogan County, Washington, United States. The population was 994 at the 2000 census and increased 3.8% to 1,032 at the 2010 census.-History:Tonasket was officially incorporated on December 16, 1927...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. He was raised in Tonasket, Washington on a cattle ranch owned by his parents, and earned his B.A. degree in physics and mathematics at Whitman College
Whitman College
Whitman College is a private, co-educational, non-sectarian, residential undergraduate liberal arts college located in Walla Walla, Washington. Initially founded as a seminary by a territorial legislative charter in 1859, the school became a four year degree granting institution in 1883...
in Walla Walla, Washington
Walla Walla, Washington
Walla Walla is the largest city in and the county seat of Walla Walla County, Washington, United States. The population was 31,731 at the 2010 census...
. Brattain earned that degree in 1924 and an M.A. degree from the University of Oregon
University of Oregon
-Colleges and schools:The University of Oregon is organized into eight schools and colleges—six professional schools and colleges, an Arts and Sciences College and an Honors College.- School of Architecture and Allied Arts :...
in 1926. He then moved eastward, taking his Ph.D. degree in physics at the University of Minnesota
University of Minnesota
The University of Minnesota, Twin Cities is a public research university located in Minneapolis and St. Paul, Minnesota, United States. It is the oldest and largest part of the University of Minnesota system and has the fourth-largest main campus student body in the United States, with 52,557...
in 1929. Brattain's advisor was John T. Tate Sr., and his thesis was on electron impact in mercury vapor. In 1928 and 1929 he worked at the National Bureau of Standards in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
, and in 1929 was hired by Bell Telephone Laboratories
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
.
Brattain's concerns at Bell Laboratories in the years before World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
were first in the surface physics of tungsten
Tungsten
Tungsten , also known as wolfram , is a chemical element with the chemical symbol W and atomic number 74.A hard, rare metal under standard conditions when uncombined, tungsten is found naturally on Earth only in chemical compounds. It was identified as a new element in 1781, and first isolated as...
and later in the surfaces of the semiconductors cuprous oxide and silicon. During World War II Brattain devoted his time to developing methods of submarine detection under a contract with the National Defense Research Council at Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...
.
Career in physics
Following the war, Brattain returned to Bell Laboratories and soon joined the semiconductorSemiconductor
A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
division of the newly-organized Solid State Department of the laboratories. William Shockley
William Shockley
William Bradford Shockley Jr. was an American physicist and inventor. Along with John Bardeen and Walter Houser Brattain, Shockley co-invented the transistor, for which all three were awarded the 1956 Nobel Prize in Physics.Shockley's attempts to commercialize a new transistor design in the 1950s...
was the director of the semiconductor division, and early in 1946 he initiated a general investigation of semiconductors that was intended to produce a practical solid state amplifier
Amplifier
Generally, an amplifier or simply amp, is a device for increasing the power of a signal.In popular use, the term usually describes an electronic amplifier, in which the input "signal" is usually a voltage or a current. In audio applications, amplifiers drive the loudspeakers used in PA systems to...
.
Crystals of pure semiconductors (such as silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
or germanium
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....
) are very poor conductors at ambient temperatures because the energy that an electron must have in order to occupy a conduction energy level is considerably greater than the thermal energy available to an electron in such a crystal. Heating a semiconductor can excite electrons into conduction states, but it is more practical to increase conductivity by adding impurities to the crystal. A crystal may be doped with a small amount of an element having more electrons than the semiconductor, and those excess electrons will be free to move through the crystal; such a crystal is an n-type semiconductor. One may also add to the crystal a small amount of an element having fewer electrons than the semiconductor, and the electron vacancies, or holes, so introduced will be free to move through the crystal like positively-charged electrons; such a doped crystal is a p-type semiconductor.
At the surface of a semiconductor the level of the conduction band can be altered, which will increase or decrease the conductivity of the crystal. Junctions between metals and n-type or p-type semiconductors, or between the two types of semiconductors, have asymmetric conduction properties, and semiconductor junctions can therefore be used to rectify electrical currents. In a rectifier, a voltage bias that produces a current flow in the low-resistance direction is a forward bias, while a bias in the opposite direction is a reverse bias.
Semiconductor rectifiers were familiar devices by the end of World War II, and Shockley hoped to produce a new device that would have a variable resistance and hence could be used as an amplifier. He proposed a design in which an electric field was applied across the thickness of a thin slab of a semiconductor. The conductivity of the semiconductor changed only by a small fraction of the expected amount when the field was applied, which John Bardeen
John Bardeen
John Bardeen was an American physicist and electrical engineer, the only person to have won the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon Neil Cooper and John Robert Schrieffer for a...
(another member of Shockley's division) suggested was due to the existence of energy states for electrons on the surface of the semiconductor.
Personal life
Brattain was a resident of Summit, New JerseySummit, New Jersey
Summit is a city in Union County, New Jersey, United States. At the 2010 United States Census, the city's population was 21,457. Summit had the 16th-highest per capita income in the state as of the 2000 Census....
. He moved to Seattle, Washington, in the 1970s where he lived until his death.
In popular culture
The starship USS Brattain, which appeared in the Star Trek: The Next GenerationStar Trek: The Next Generation
Star Trek: The Next Generation is an American science fiction television series created by Gene Roddenberry as part of the Star Trek franchise. Roddenberry, Rick Berman, and Michael Piller served as executive producers at different times throughout the production...
episode "Night Terrors," was named after the scientist.
External links
- The USS Brattain at Memory Alpha: http://memory-alpha.org/wiki/USS_Brattain