Draw E-K diagram and explain briefly.
Answers
Answered by
65
An E-k diagram shows characteristics of a particular semiconductor material. It shows the relationship between the energy and momentum of available quantum mechanical states for electrons in the material.
First, consider a basic E-k band diagram like this one (the x-axis can be either momentum, pp, or wavenumber, kk, since p=ℏkp=ℏk):
In this diagram you can see a few things:
The band gap (EG), which is the difference in energy between the top of the valence band and the bottom of the conduction band.
The effective mass of electrons and holes in the material. This is given by the curvature of each of the bands.
This diagram indicates (diagramatically) how the actual electron states are equally spaced in k-space. Which means that the density of states in E (ρ(E)ρ(E)) depends on the slope of the E-k curve.
First, consider a basic E-k band diagram like this one (the x-axis can be either momentum, pp, or wavenumber, kk, since p=ℏkp=ℏk):
In this diagram you can see a few things:
The band gap (EG), which is the difference in energy between the top of the valence band and the bottom of the conduction band.
The effective mass of electrons and holes in the material. This is given by the curvature of each of the bands.
This diagram indicates (diagramatically) how the actual electron states are equally spaced in k-space. Which means that the density of states in E (ρ(E)ρ(E)) depends on the slope of the E-k curve.
Attachments:
Answered by
11
In K-P Model, an equation is obtaining for energy Eigen values of an electron moving in a periodic potential and his observed that electrons have energy values only between allowed energy bands and these allowed energy bands are separated by forbidden gap. Therefore this continuity in energy bands. Due to the values-
∝a= ±π
∝= (±π)/a
Where,
n = 1,2,3,...
n ≠ 0
Once again,
We have parabolic E-K Diagram.
Attachments:
Similar questions