Walter Houser Brattain 33133 222235546 2008-06-28T06:54:13Z Emerson7 191157 cleanup infobox; {{Infobox Scientist |name = Walter Brattain |image = Walter Houser Brattain.jpg |imagesize = 160px |caption = Walter Houser Brattain (1902-1987) |birth_date = [[February 10]], [[1902]] |birth_place = [[Amoy, China]] |death_date = [[October 13]], [[1987]] |death_place = [[Seattle, Washington]], [[USA]] |nationality = [[United States]] |field = [[Physicist]], [[Inventor]] |work_institutions = [[Whitman College]]</br>[[Bell Laboratories]] |alma_mater = [[Whitman College]]</br>[[University of Oregon]]</br>[[University of Minnesota]] |doctoral_advisor = [[John Torrence Tate, Sr.]] |doctoral_students = |known_for = [[Transistor]] |prizes = [[Nobel Prize in Physics]] (1956) }} '''Walter Houser Brattain''' ([[February 10]], [[1902]]–[[October 13]], [[1987]]) was an [[United States|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]]. == Early life and education == He was born to Ross R. Brattain and Ottilie Houser in [[Amoy, China]] on [[February 10]], [[1902]] and spent the early part of his life in [[Springfield, Oregon]] and [[Washington]] in the [[United States]]. He was raised in Washington on a cattle ranch owned by his parents, and earned his B.S. 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, 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 Labs|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]]. == Career in physics == Following the war, Brattain returned to Bell Laboratories and soon joined the [[semiconductor]] 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. ==References== {{reflist}} * [http://nobelprize.org/physics/laureates/1956/brattain-bio.html Walter H. Brattain – Biography] {{Nobel Prize in Physics Laureates 1951-1975}} {{DEFAULTSORT:Brattain, Walter}} [[Category:1902 births]] [[Category:1987 deaths]] [[Category:American inventors]] [[Category:American physicists]] [[Category:Americans of Scottish descent]] [[Category:Experimental physicists]] [[Category:Nobel laureates in Physics]] [[Category:Quantum physicists]] [[Category:Scientists at Bell Labs]] [[Category:Semiconductor physicists]] [[Category:Whitman College alumni]] [[Category:University of Minnesota alumni]] [[Category:University of Oregon alumni]] [[bn:ওয়াল্টার হাউজার ব্র্যাটেইন]] [[bg:Уолтър Братейн]] [[ca:Walter Houser Brattain]] [[cs:Walter Houser Brattain]] [[de:Walter H. Brattain]] [[es:Walter Houser Brattain]] [[eo:Walter Houser Brattain]] [[fr:Walter Houser Brattain]] [[gl:Walter Houser Brattain]] [[ko:월터 브래튼]] [[hi:वॉल्टर ब्रैट्टैन]] [[io:Walter H. Brattain]] [[id:Walter Brattain]] [[it:Walter Houser Brattain]] [[sw:Walter Brattain]] [[ml:വാള്‍ട്ടര്‍ എച്ച്. ബ്രാറ്റെയിന്‍]] [[nl:Walter Brattain]] [[ja:ウォルター・ブラッテン]] [[no:Walter Houser Brattain]] [[oc:Walter H. Brattain]] [[pl:Walter Houser Brattain]] [[pt:Walter Houser Brattain]] [[ro:Walter Houser Brattain]] [[ru:Браттейн, Уолтер Хаузер]] [[sl:Walter Houser Brattain]] [[fi:Walter Houser Brattain]] [[sv:Walter H. Brattain]] [[zh:沃尔特·豪泽·布喇顿]]