On April 26th 1961, the silicon integrated circuit was patented by Robert Noyce (No. 2,981,877).
Robert (Norton) Noyce was a U.S. engineer and coinventor (1959), with Jack Kilby, of the integrated circuit, a system of interconnected transistors on a single silicon microchip. He held sixteen patents for semiconductor devices, methods, and structures. In 1968, he and colleague Gordon E. Moore cofounded N.M. Electronics, which later was renamed Intel Corporation. Noyce served as Intel’s president and chairman (1968-75), then as vice chairman until 1979.
Src: Today in Science History
It is also worth mentioning this MIT graduate went on to co-found Fairchild Semiconductor and the production of the first commercially practical integrated circuit.