At Bell Laboratories, Brattain and Bardeen worked to develop electronic replacements for vacuum tubes. They experimented with using copper and copper oxide to regulate devices through rectification, but these devices did not work. They made a breakthrough when exploring the behavior of silicon samples exposed to light, discovering an "internal barrier" effect. After further experimenting and refining silicon samples, they were able to amplify power and voltage at a high frequency, inventing the first transistor. Kelly then clamped down secrecy at Bell Labs to protect their patentable discovery.

1. The Road to Discovery http://people.clarkson.edu/~ekatz/scientists/brattain3.jpg http://www.ieee.org/portal/cms_docs_sscs/sscs/07Spring/HR-1stTransistor.jpg http://www.ieee-virtual-museum.org/media/Gfu2CV9zswnp.jpg

3. Rectification Barrier Barrier

10. The Transistor is Born Brattain & Gibney observe field effect in silicon sample; amplified effect when electrolytes are used Bardeen suggests n-type germanium; discover method to raise minority carrier population in n-layer Increase frequency response by allowing direct metal-semiconductor slab contact, eliminating “gu”. Now able to amplify power & voltage at a high frequency response Shockley proposes applying voltage through “gu” at the p-n junction rather than point contacts; Brattain anxious to attempt, but gets the flu and experiment is forgotten. http://nobelprize.org/educational_games/physics/transistor/function/images/bild11.gif