A monolithic integrated circuit (IC) also known as microchip, silicon chip, computer chip or chip is basicaly a miniaturized electronic circuit that consists of mainly of semiconductor devices, as well as passive components. This circuit is manufactured in the surface of a thin substrate of semiconductor material. A hybrid integrated circuit is a miniaturized electronic circuit constructed of individual semiconductor devices, as well as passive components, bonded to a substrate or circuit board.
The integrated circuit was first conceived by a radar scientist, Geoffrey W.A. Dummer (born 1909), working for the royal radar establishment of the British ministry of defense, and published in Washington, D.C. on may 7, 1952. Dummer unsuccessfully attempted to build such a circuit in 1956.
The first integrated circuits were manufactured independently by two scientists; jack Kilby of Texas instruments filed a patent for a “solid circuit” made of germanium on February 6,1959. Kilby received patent 3261081, and U.S. patent 3434015. Robert Noyce of Fairchild semiconductor was awarded a patent for a more complex “Unitary circuit” made of silicon on April 25, 1961. Noyce credited Kurt lehovec isolation caused by the action of a biased p-n junction (the diode) as a key concept behind the IC.
Integrated circuits can be classified into analog, digital and mixed signal. Digital integrated circuits can contain anything from one to millions of logic gates, Flip-flops, multiplexers, and other circuits in a few square millimeters. The small size of these circuits allows high speed, low power dissipation, and reduced manufacturing cost compared with board-level integration. These digital ICs, typically microprocessors, DSPs, and micro controllers work using binary mathematics to process “zero” signals.
Analog ICs, such as sensors, power management circuits, and operational amplifiers, work by processing continuous signals. They perform functions like amplification, active filtering, demodulation, mixing, etc. analog ICs ease the burden on circuit designers by having expertly designed analog circuits available instead of designing a difficult analog circuit from scratch.
ICs can also combine analog and digital circuits on a single chip to create functions such as A/D converters and D/A converters. Such circuits offer smaller size and lower cost, but must carefully account for signal interference.