What are Semiconductors?

About Semiconductors

• Semiconductors are materials whose electrical conductivity lies between conductors and insulators and can be precisely controlled.
• Silicon is the most widely used semiconductor material, while germanium and compound semiconductors such as gallium nitride (GaN) are also used in specific applications.
• Their ability to control the flow of electric current makes them fundamental to modern electronic devices.
• Semiconductors form the basic building blocks of integrated circuits (ICs), transistors, diodes, sensors and microprocessors.

How Do Semiconductors Work?

• Controlled Conductivity: Their conductivity can be modified by factors such as temperature, light, electric fields and addition of impurities.
• Doping: Small quantities of impurities are added to semiconductor materials to create n-type and p-type semiconductors.
• Transistors: Combining different semiconductor regions enables the creation of transistors that can switch or amplify electrical signals.
• Integrated Circuits: Millions or billions of transistors can be fabricated on a single chip to perform complex computational tasks.

Types of Semiconductors

• Intrinsic Semiconductors: Relatively pure semiconductor materials such as pure silicon.
• Extrinsic Semiconductors: Semiconductors whose electrical properties are modified through doping:
  • n-type: Uses donor impurities and has electrons as the majority charge carriers
  • p-type: Uses acceptor impurities and has holes as the majority charge carriers
• Compound Semiconductors: Made from two or more elements, such as GaN and gallium arsenide (GaAs), and used in applications including high-frequency communication and power electronics.

Applications

• Consumer Electronics: Smartphones, computers, televisions and other electronic devices.
• Automobiles: Electronic control systems, electric vehicles and advanced driver-assistance systems.
• Communication: Mobile networks, optical communication and satellite systems.
• Artificial Intelligence: High-performance processors and AI accelerators.
• Renewable Energy: Solar cells and power-management systems.

Conclusion

Semiconductors form the foundation of modern electronics, enabling technologies ranging from smartphones and automobiles to AI, telecommunications, defence systems and renewable energy.