Transistor
The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Julius Edgar Lilienfeld patented a field-effect transistor in 1926 but it was not possible to actually construct a working device at that time. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley. The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.
John Bardeen
Bardeen was honored on a March 6, 2008, United States postage stamp as part of the "American Scientists" series designed by artist Victor Stabin. The $0.41 stamp was unveiled in a ceremony at the University of Illinois. His citation reads: "Theoretical physicist John Bardeen (1908–1991) shared the Nobel Prize in Physics twice — in 1956, as co-inventor of the transistor and in 1972, for the explanation of superconductivity. The transistor paved the way for all modern electronics, from computers to microchips. Diverse applications of superconductivity include infrared sensors and medical imaging systems." The other scientists on the "American Scientists" sheet include biochemist Gerty Cori, chemist Linus Pauling and astronomer Edwin Hubble.