Early developments of the integrated circuit go back to 1949, when the German engineer Werner Jacobi (de) (Siemens AG) filed a patent for an integrated-circuit-like semiconductor amplifying device showing five transistors on a common substrate in a 3-stage amplifier arrangement. Jacobi disclosed small and cheap hearing aids as typical industrial applications of his patent. An immediate commercial use of his patent has not been reported.
The idea of the integrated circuit was conceived by a radar scientist working for the Royal Radar Establishment of the British Ministry of Defence, Geoffrey W.A. Dummer (1909–2002). Dummer presented the idea to the public at the Symposium on Progress in Quality Electronic Components in Washington, D.C. on 7 May 1952. He gave many symposia publicly to propagate his ideas, and unsuccessfully attempted to build such a circuit in 1956.
A precursor idea to the IC was to create small ceramic squares (wafers), each one containing a single miniaturized component. Components could then be integrated and wired into a bidimensional or tridimensional compact grid. This idea, which looked very promising in 1957, was proposed to the US Army by Jack Kilby, and led to the short-lived Micromodule Program (similar to 1951’s Project Tinkertoy). However, as the project was gaining momentum, Kilby came up with a new, revolutionary design: the IC.
Robert Noyce credited Kurt Lehovec of Sprague Electric for the principle of p-n junction isolation caused by the action of a biased p-n junction (the diode) as a key concept behind the IC.
Jack Kilby’s original integrated circuit
Newly employed by Texas Instruments, Kilby recorded his initial ideas concerning the integrated circuit in July 1958, successfully demonstrating the first working integrated example on 12 September 1958. In his patent application of 6 February 1959, Kilby described his new device as “a body of semiconductor material … wherein all the components of the electronic circuit are completely integrated.” The first customer for the new invention was the US Air Force.
Kilby won the 2000 Nobel Prize in Physics for his part of the invention of the integrated circuit. Kilby’s work was named an IEEE Milestone in 2009.
Noyce also came up with his own idea of an integrated circuit half a year later than Kilby. His chip solved many practical problems that Kilby’s had not. Produced at Fairchild Semiconductor, it was made of silicon, whereas Kilby’s chip was made ofgermanium.
Fairchild Semiconductor was also home of the first silicon gate IC technology with self-aligned gates, which stands as the basis of all modern CMOS computer chips. The technology was developed by Italian physicist Federico Faggin in 1968, who later joined Intel in order to develop the very first Central Processing Unit (CPU) on one chip (Intel 4004), for which he received the National Medal of Technology and Innovation in 2010.