Semiconductors
Silicon and germanium (plus a few other materials) have half-filled valence
shells and are thus neither good conductors nor good insulators. Known as
semiconductors, they have unique electrical properties that make them
important to the electronics industry. The most important material is silicon.
It is used to make transistors, diodes, integrated circuits, and other electronic
devices. Semiconductors have made possible personal computers, VCRs,
portable CD players, calculators, and a host of other electronic products. You
will study them in great detail in your electronics courses.