A conductive material is one that opposes very little resistance to the passage of an electric current. This means that they allow the flow of electricity through them. The reason for the conductivity of some materials is simple. Atoms of this type of material have few electrons in their valence shell. This results in not much energy being needed to make these pass from one atom to another, thus resulting in the flow of electricity.
Some examples of conductive materials include metals such as copper, aluminum, gold, and silver. In fact, copper is the most widely used material in the world for the transport of electrical energy. Although silver is a better conductor of electricity, copper is much cheaper than it. Also, other non-metallic materials such as graphite and salt solutions are excellent examples of conductors.
In contrast, an insulating material does not allow electricity to flow through it; that is, it opposes total resistance to the flow of current. Insulating materials are usually used to protect or isolate electrical currents. This means that they do not allow electricity to be diverted from the semiconductor material that carries it. Some insulating materials include plastic, (dry) wood, and rubber.
Finally, a semiconductor material is one that can behave as a conductive material or an insulating material depending on each situation. Some of the factors that influence a semiconductor material are radiation, temperature, magnetic field, and pressure. Some semiconductor elements are cadmium, aluminum, carbon and phosphorus. However, the most widely used semiconductor element is silicon.
Semiconductor materials only allow electrical flow in one direction. Every day they are found inside electrical devices, such as computer microprocessors or smartphones.