Semiconductors are everywhere. The computers, televisions, and phones we enjoy today would not be possible were it not for the development of semiconductor technology during the 19th and especially the 20th century. But what are semiconductors, how do they function, and how do they make possible the electronics we rely on every day?
In the study of electromagnetics, materials are grouped into two broad classifications: conductors and insulators. A conductor is a material which holds (or can hold) a moving electrical charge. Insulators are the opposite. Electrical charges do not move readily through them. Semiconductors, as the name suggests, fall somewhere between insulators and conductors. Because they are not pure conductors or pure insulators, they are very useful for modulating electrical currents in ways that are needed to power electronics. Most of the semiconductors used today are man-made, and have been designed to have the specific properties of electrical conductivity needed for whatever device they are used in.