Bell Labs demonstrates the transistor

Telephones, radio equipment, and computers used vacuum tubes for amplification and switching during the first half of the twentieth century. Power consumption, heat, and maintenance created incentives for smaller devices. Bell Laboratories studied electrical behaviour in solids. Semiconductor surfaces, material purity, contact positions, and preparation complicated experiments. Work involving Bardeen, Brattain, Shockley, and colleagues joined theoretical explanations with practical investigation of how electrons moved through particular manufactured structures.

References: [1]

In December 1947 Bardeen and Brattain demonstrated amplification using germanium and closely spaced metal contacts. A paper publicized results in 1948. The initial point-contact device was difficult to manufacture, and junction transistors and other designs followed. Semiconductor charge carriers could control current in compact components. Turning a laboratory result into dependable products required purification, crystal growth, packaging, and procedures capable of producing repeatable performance across many individual devices.

References: [1]

Transistors entered hearing aids, portable radios, communication systems, and computers. Silicon and improved processes broadened applications, eventually supporting many devices manufactured together as integrated circuits. Growing markets also sustained materials and testing industries. Design and fabrication became increasingly specialized activities. Equipment changed in size, lifetime, price, and power requirements. Information processing entered additional settings as semiconductor production developed into an industrial field requiring continuing investment in both scientific understanding and manufacturing control.

References: [1]