A semiconductor is a material that has electrical conductivity between that of a conductor and an insulator. Semiconductors are used in electronic devices such as transistors, diodes, and integrated circuits. They are essential components in modern electronics and are used in a wide range of applications, including computers, smartphones, and televisions. Silicon is the most commonly used semiconductor material, but other materials such as gallium arsenide and germanium are also used in certain applications.
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Google Gemini AI
Sep 6
Definition:
A semiconductor is a material with an electrical conductivity that falls between that of a good conductor, like metal, and that of an insulator, like rubber. Semiconductors have the ability to control the flow of electrical current, making them essential for modern electronics.
Properties:
- Electrical Conductivity: Semiconductors have an energy gap between their valence band and conduction band. At room temperature, the gap is large enough to prevent electrons from jumping from the valence band to the conduction band, making them poor conductors of electricity. - Doping: The electrical conductivity of semiconductors can be altered by doping, which is the intentional addition of impurities. Donor impurities donate electrons to the semiconductor, increasing its conductivity (n-type semiconductor), while acceptor impurities create holes (vacant electron positions) that can be filled by electrons, decreasing conductivity (p-type semiconductor). - Band Gap: The band gap of a semiconductor determines the energy required for an electron to move from the valence band to the conduction band. Wide-band gap semiconductors (e.g., diamond) are used for high-power applications, while narrow-band gap semiconductors (e.g., indium gallium arsenide) are used for low-power devices. - Crystalline Structure: Semiconductors can exist in both crystalline and amorphous forms. Crystalline semiconductors have a regular, ordered atomic arrangement, while amorphous semiconductors have a disordered, non-crystalline structure.
Types of Semiconductors:
- Intrinsic semiconductors: Pure semiconductors with no impurities. They have a high electrical resistance. - Extrinsic semiconductors: Semiconductors with impurities added through doping. They have lower electrical resistance than intrinsic semiconductors. - Elemental semiconductors: Made from a single element, such as silicon or germanium. - Compound semiconductors: Formed by combining two or more elements, such as gallium arsenide or indium phosphide.
Applications:
Semiconductors are the foundation of modern electronics and are used in a wide range of devices, including: