The manufacture of an integrated circuit is a complex process, which may embody 50 or more separate stages. The crystals are first sliced into wafers or circular discs. Individual, identical chips are made simultaneously on each wafer in a series of optical and chemical processes. These processes introduce specific impurities into defined areas of the chip, forming semiconductor devices. The devices are connected electrically by deposits of aluminium, and the wafer is then broken into separate chips, which are individually encapsulated.
Integrated circuits can serve many functions.
Microprocessor chips carry out arithmetical operations and can control other circuits. Other chips may carry computer programs, and applications-specific circuits are tailored to the requirements of a particular device. The Penguin Dictionary of Psychology 3. Oxford University Press 5. All rights reserved.