Semiconductors are classified as one type of material, which acts as an intermediate between conductors and insulators. A semiconductor has a conductivity value associated with it, which is neither that of an insulator nor that of a conductor but lies between the two. Let’s dive into more deeper understanding semiconductors:
Definition
Semiconductor materials have some electrical properties that help in operating some electronic devices. In this, the resistivity decreases with the increased temperature, while metal behaves contrarily in this regard. It helps in the conduction of electricity at times or conditions but not at all-i.e., integrated circuits, transistors, and diodes all use semiconductors. It even electrically conducts concerning heat and light.
Band Theory
Insulators are materials having the greatest energy gap between conduction and valence bands, thus even with some energy applied, electron movement from the valence band to the conduction band does not occur-the result being that conduction of electricity is not possible in these materials according to band gap theory.
Semiconductors are the bridge between conductors and insulators; in these materials electrons will move from the valence band to the conduction band upon application of some amount of energy, but under normal conditions they will not conduct. To become conductive, one must provide energy equal to the band gap between the valence and conduction bands.
Properties
Dopant Introduction: Impurity introduction in semiconductors is called doping, which otherwise implies the controlled introduction of impurities into semiconductors, such as producing excess charge carriers (N-type) or “holes” (P-type), for conductivity manipulation.
Temperature Sensitivity: The conductivity of semiconductors varies with temperature. Hence, it suits some applications, such as thermistors and temperature sensors.
Energy Gap: Semiconductors possess a band gap, which is the energy range in between the valence band, within which the electrons are strongly bound, and the conduction band, which makes movement of electrons possible. Thus, these bands decide the conduction or insulating nature of semiconductors.
Heat Conductance: They also possess intermediate thermal conductivity, which is why they can manage controlled heat dissipation. In other words, this controlled heat dissipation is critical in the case of integrated circuits.
Mechanical Effect: Resistance in semiconductors can change due to mechanical stress (piezo resistivity), especially used in strain gauges and pressure sensors.
Photo Sensitivity: Certain kinds of semiconductors behave to become more conductive under exposure to light. This property has applications in photodetectors and solar cells.
Quantum Aspects: Semiconductors show quantum effects on a nanoscale. These are used in advanced applications found in quantum dots and quantum well structures.
Carrier Mobility: The movement ability of charge carriers (electrons and holes) within semiconductors is determined by carrier mobility; it influences the efficiency of the devices and the speed.
Uses
CPU and GPU, made by Semiconductor technology. Modern-day LED and OLED use Semiconductor materials. Many devices for communication, such as Routers, Modems, Satellite, and GPS, use Semiconductor chips. The lighting systems in which LED Light is built are made using semiconductor materials.
They develop the chemical and electrical properties of Semiconductors to serve electronic devices such as LEDs, Solar Cells, etc. Without these materials, our life would not be interesting and would certainly need a lot of modifications. Understanding Semiconductors has helped us know our everyday devices better.
