The twentieth-century age of electronics traced its roots to the 1906 invention of the triode vacuum tube, which marked the birth of modern radio, and the invention of the transistor after World War II ushered in a new era of solid-state electronics. As engineers designed increasingly complex equipment, the difficulty of interconnecting large numbers of individual transistors and other components to form electronic circuits became a barrier to further progress, creating a need for a reliable, cost-effective way to produce and interconnect the components. Technical research groups in the United States and abroad began work on the problem. In 1958, Jack St. Clair Kilby, an engineer at Texas Instruments in Dallas, designed and built an integrated circuit with all the components formed in a single piece of semiconductor material. On September 12, 1958, he demonstrated this first working integrated circuit to Texas Instruments personnel in the semiconductor building on this site. This conceptual breakthrough and work elsewhere led to development of the microchips at the core of modern electronic products, including consumer electronics, digital computers, defense systems, and global communications networks.