A semiconductor is a material that has electrical conductivity properties that fall between those of a conductor, such as copper, and an insulator, such as glass. Semiconductors are used as a foundation for computers and other electronic devices. Some key characteristics of semiconductors include:

• Resistivity: The resistivity of a semiconductor falls as its temperature rises, which is the opposite behavior of metals.
• Valence Bands: Semiconductors in their natural state are poor conductors because their valence bands are filled, preventing the flow of new electrons.
• Doping: Semiconducting materials can be modified through techniques such as doping or gating to behave like conducting materials. Doping involves adding impurities to the semiconductor, which can create excess or shortage of electrons, resulting in n-type and p-type semiconductors.
• Types of Semiconductors: The most common semiconducting materials are crystalline solids, but amorphous and liquid semiconductors are also known. Some wider-bandgap semiconductor materials are sometimes referred to as semi-insulators.

Semiconductors are used in electronic devices such as diodes, integrated circuits, and transistors. They are also used in solid-state storage and are a popular component of electronic chips made for computing components and a variety of electronic devices.