Electronic device that operates on the basis of the electric, magnetic, or optical properties of a solid material, especially one that uses a solid crystal in which an orderly three-dimensional arrangement of atoms, ions, or molecules is repeated throughout the entire crystal.
Synthetic crystals of elements such as silicon , gallium arsenide, and germanium are used in transistors , rectifiers, and integrated circuits . The first solid-state device was the "cat's whisker" (1906), in which a fine wire was moved across a solid crystal to detect a radio signal. See also semiconductor .