Transistors

The first patent^[1] for the field-effect transistor principle was filed in Canada by Austrian-Hungarian physicist Julius Edgar Lilienfeld on October 22, 1925, but Lilienfeld did not publish any research articles about his devices. In 1934 German physicist Dr. Oskar Heil patented another field-effect transistor.

On 17 November 1947 John Bardeen and Walter Brattain, at AT&T Bell Labs, observed that when electrical contacts were applied to a crystal of germanium, the output power was larger than the input. William Shockley saw the potential in this and worked over the next few months greatly expanding the knowledge of semiconductors and is considered by many to be the "father" of the transistor. The term was coined by John R. Pierce.The transistor is considered by many to be the greatest invention of the twentieth-century,^[2] or as one of the greatest.^[3] It is the key active component in practically all modern electronics. Its importance in today's society rests on its ability to be mass produced using a highly automated process (fabrication) that achieves astonishingly low per-transistor costs.

Although several companies each produce over a billion individually-packaged (known as discrete) transistors every year,^[4] the vast majority of transistors produced are in integrated circuits (often shortened to IC, microchips or simply chips) along with diodes, resistors, capacitors and other electronic components to produce complete electronic circuits. A logic gate consists of about twenty transistors whereas an advanced microprocessor, as of 2006, can use as many as 1.7 billion transistors (MOSFETs).^[5] "About 60 million transistors were built this year [2002] ... for [each] man, woman, and child on Earth."^[6]