What Is a Semiconductor and What Is It Used for?

Semiconductors are at the heart of it all. A semiconductor is a special type of material that doesn’t fully conduct electricity like metals, but it’s not a total insulator like glass either. Instead, it can conduct electricity only under certain conditions. This unique property is exactly what makes semiconductors essential for building components like transistors and diodes, which power the devices we use every day.

In the context of electronics, you’ll find that semiconductors are substances with electrical conductivity falling between that of insulators like rubber or glass and conductors like metals. We rely on these substances because they have special qualities that make them essential parts of electronic devices. Modern electronics heavily depend on semiconductors, which serve as the basis for many different semiconductor devices.

Key characteristics of semiconductors include

Conductivity: Semiconductors have a moderate level of electrical conductivity. They conduct electricity better than insulators but not as effectively as conductors.

Band Gap: Semiconductors have a specific energy band gap between their valence band (the lowest energy level with occupied electrons) and their conduction band (the energy level where electrons can move freely). This band gap determines whether the material behaves as a conductor or an insulator under specific conditions.

Doping: The conductivity of semiconductors can be modified through a process called doping. This involves intentionally adding impurities (atoms of different elements) to the semiconductor material to increase its electron or hole (positively charged carriers) concentration.

Carrier Mobility: Semiconductors allow the movement of charge carriers (electrons or holes) under the influence of an electric field.

Semiconductors serve as the foundation of various electronic components, including

Diodes: Semiconductor components are used frequently as rectifiers that only permit electricity to flow in one direction.
Transistors: The building blocks of digital electronics, amplifiers, and switches that regulate the flow of electrical current.
Integrated circuits (ICs): have thousands to billions of transistors and other parts on a single substrate.
Solar cells: Machines that use semiconductors to transform solar energy into electrical energy.
Light-Emitting Diodes (LEDs): Semiconductors known as Light-Emitting Diodes (LEDs) release light when current flows through them.

Modern technology has been revolutionized by the capacity to control and modify semiconductors, which has led to the development of sophisticated electronic gadgets ranging from computers and smartphones to medical equipment and renewable energy systems.