Conduction Band – Important Terminologies

Following are some important terms related to conduction band which need to be learnt

• Fermi Level
• Conduction Electron
• Conductivity
• Band Gap
• Electron Mobility

Fermi Level

Fermi level refers to an energy level at which there is zero probability of occupation. Fermi level represents the splitting of occupied and unoccupied electron states at absolute zero temperature. The Fermi level is of great importance in understanding the electronic properties of materials, and especially helps one decide whether a material will act as conductor or insulator.

Conduction Electron

Conduction Electrons are the electrons in conduction band of a material responsible for conductivity of the material. These electrons are free, have enough energy to travel anywhere and assist in electrical conductivity. In metals the conduction band partially overlaps with valence band, so electrons can move freely across energy bands within a small range and metals conduct electric Current well.

Conductivity

Conductivity is the ability of a material to conduct electric current. A material is conducting or not depends on the existence of free electrons in the conduction band. High conductivity materials such as metals permit electrons to move freely; insulators prevent electron flow. Performance of electronic devices depends on one important property conductivity. Conductivity is inverse of resistivity. Hence, conductivity is given as

σ = 1/ρ

where,

• σ is Conductivity
• ρ is Resistivity

Band Gap

Band gap is the energy difference between the valence and conduction bands. It determines a material’s electrical properties. The larger the gap, an insulator; and a small or zero gap is typical of conductors. Between insulators and conductors, semiconductors have a moderate band gap that provides for electronic conductivity limited by conditions.

Electron Mobility

Electron mobility is a measure of how easily electrons can pass through in response to an electric field. The electrons in the conduction band are mobile, so that electrical conductivity is efficient. The concept is important in the design of electronic components and understanding the operation of semiconductor devices. The formula of Electron Mobility is given as

μ_n = eτ/m*_n

where,

• μ_n is Mobility of Electron
• e is Charge of Electron
• τ is Relaxation Time
• m*_n is Mass of Electron

Conduction Band is an electron band where electrons are arranged after jumping from the valence band when they are excited. The presence of electrons in the conduction band allows the matter to allow the flow of electricity through them. This explains why metals are good conductors of electricity as their conduction band bs are partially filled with electrons. This special band inside solid-state materials (like metals or semiconductors) is like a little express highway for electrons to travel on.

In this article, we will learn what is Conduction Band, Band Theory of Electrons, Difference between Conduction Band and Valence Band, and related terminologies.