A charge carrier is a conduction hole or free electron that can move freely within a semiconductor. Now, before we move further, you must learn about semiconductors. An element or compound that conducts electricity under some circumstances but not others is known as a semiconductor. Semiconductors are useful for managing electric current due to their characteristic of being neither a good insulator nor a good conductor.
A semiconductor’s electrical conductivity is influenced by a number of factors, such as the voltage or current that is applied, as well as the amount of infrared, ultraviolet, or visible light that strikes the surface. This is the rationale behind the usage of semiconductors in photovoltaic systems.
What are semiconductors?
The term semiconductors refer to a wide variety of substances. These materials’ valence shells typically have four electrons because they are not prone to losing electrons (creating free electrons) or gaining electrons.
Antimony, arsenic, boron, carbon, germanium, selenium, silicon, sulphur, and tellurium are examples of elemental semiconductors—materials that contain just one element. The most well-known of them is silicon, which serves as the foundation for many electric circuits.
Semiconductors establish perfect covalent connections with four nearby atoms because they have four electrons in their valence shell. A crystal lattice is formed as a result. No unbound electrons can carry current in this pristine lattice. Due to this, a real semiconductor is created when a crystal structure has impurities, and it is these impurities that give the substance its unique features.
The charge carriers in the majority of electric circuits and devices are negatively charged electrons that move as a result of a voltage to produce an electric current. However, the majority of circuitry is created using conventional current, which employs positive charges that flow in the obverse of electrons.
Also Read: What is a Charge?
Another charge carrier besides electrons and fictitious positively charged particles is holes. Because holes are empty valence electron orbitals, they symbolise an electron shortage that is free to flow throughout a material.
In semiconductor devices like diodes, a current is produced by the convergence of two different charge carriers, electrons and holes. For additional details on how charge carriers affect conduction in a diode, see diode functioning.