Crystal Fire #5

Walter Brattain began working at Bell Labs in 1929. Mervin Kelly was a researcher at Bell Labs who became its director of research in 1936. He envisioned telephone switches being electronic rather than mechanical. William Shockley was Kelly’s first hire after a hiring freeze was lifted in 1936. Kelly hired Shockley for the latter’s knowledge of quantum mechanics. Shockley took Kelly’s vision as a guiding light. For the next several years, Bell Labs grew its research staff with specialists in quantum mechanics. In 1937 Clinton Davisson of Bell Labs won the Nobel Prize for his experiments that electrons behaved like waves.

Brattain and Joseph Becker studied the papers of Walter Shottky and Nevill Mott (neither at Bell Labs). The papers said that whenever a metal and a semiconductor come into contact, a double layer of charge crops up – positive on one side and negative on the other – because of the difference in work functions of the two materials. This leads to a kind of “hill” that electrons must surmount if they are to cruise from one side to the other. “Because this hill is asymmetric, with a steep cliff on the metal side and a shallow slope on the other, electrons move far more readily from semiconductor to metal than in the opposite direction." This finally provided a satisfactory explanation of rectification, which had mystified scientists for 65 years. Shockley, Brattain, and Becker attempted fabricating devices to make use of this effect. Not only was progress slow, it was interrupted with work on topics like radar, submarine detection, mines, and torpedoes due to World War II.