Figure 3-15. The microprocessor is the equivalent of the CPU in a mainframe
computer.
(3) Silicon chip. The microprocessor, or integrated circuit (its original but
rarely used name), fits on a single silicon semiconductor chip, no larger and sometimes
even smaller than a fingernail. (Silicon, the main ingredient of sand, is the second most
abundant chemical element after oxygen, which makes it cheap. Even purer forms of
silicon are "grown" synthetically in a process similar to that involved in making rock
candy.)
integrated circuit: electronic circuit whose components are etched on a single,
small piece of semiconductor material, usually a silicon chip, less than 1/8-inch
square; permits faster, cheaper processing than with the transistors of second
generation computers.
semiconductor: a solid crystalline substance used in microprocessors; its
electrical conductivity falls between that of a metal and an insulator. Silicon is a
semiconducting element.
Figure 3-16. An integrated circuit (or silicon chip) is scarcely as large as an infant's nail.
MD0057
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