The Ultimate Transistor Timeline: The transistor's amazing evolution from point contacts to quantum tunnels

EVEN AS THE INITIAL sales receipts for the first transistors to hit the market were being tallied up in 1948, the next generation of transistors had already been invented (see “The First Transistor and How it Worked,” p. 24). Since then, engineers have reinvented the transistor over and over again, raiding condensed-matter physics for anything that might offer even the possibility of turning a small signal into a larger one.