What are the different types of semiconductors?

There are two types of semiconductors: intrinsic and extrinsic.

Intrinsic semiconductors are pure materials like silicon or germanium that have a balanced number of electrons and holes. At room temperature, these materials have a small number of free electrons and holes, but when heated, more electrons are excited into the conduction band, increasing conductivity.

Extrinsic semiconductors are doped with impurities to increase conductivity. N-type semiconductors have impurities like phosphorus or arsenic added, which have extra electrons that can move freely. P-type semiconductors have impurities like boron or aluminum added, which have fewer electrons and create holes that can move freely.

When an n-type and p-type semiconductor are brought together, a p-n junction is formed. This junction creates a depletion region where there are no free electrons or holes. When a voltage is applied, the depletion region narrows and electrons and holes can flow across the junction, creating a current.

Semiconductors are used in many electronic devices, including transistors, diodes, and solar cells. Understanding the different types of semiconductors and how they work is crucial for the development of new technologies.