The band theory convinced scientists that a solid state(small, simple, one-piece) device constructed from semiconductor materials could do the same thing as the vacuum tube. This discovery started a quest that ultimately would change electronics and our lives forever. The first success in the quest was achieved at Bell Laboratories in 1947/1948, by John Bardeen and Walter Brattain. They placed a solid piece of semiconductor made of germanium, a silicon- like chemical element, in a special way between metal contacts and