Hi Friends,
There is always a confusion for the beginners about the difference between an electron and a hole. Let us find out the differences so that the going gets easy in the electronic stream.
1) An electron is a free charge carrier which contributes to current in the conduction band.
A hole is a vacancy created due to the absence of an electron.
2) Electron current is movement of the electrons in the conduction band but the direction of current will be
in the direction of opposite to that of an electron movement.
Hole current is a bit confusing but read it carefully, we already know that a hole is an absence of electron
so there is no charge but how will it still contribute to current? Hole current is also contribution of the
electrons. Electrons break the bond in the conduction band and replaces the vacancy available. So that
now vacancy is created in other place. This seems like hole is moving but actually electron is moving in
the valance band. Thus current due to holes is always in the direction of motion of hole i.e., direction
opposite to movement of electrons.
3) Electron always have greater mobility than hole because an electron in conduction band is free charge
carrier all the energy given is taken for mobility but a for a hole movement an electron in valence band
must break a bond and then move so some energy is lost. That is why electron has higher mobility than
hole.
Thanks all.(Any doubts?)
There is always a confusion for the beginners about the difference between an electron and a hole. Let us find out the differences so that the going gets easy in the electronic stream.
1) An electron is a free charge carrier which contributes to current in the conduction band.
A hole is a vacancy created due to the absence of an electron.
2) Electron current is movement of the electrons in the conduction band but the direction of current will be
in the direction of opposite to that of an electron movement.
Hole current is a bit confusing but read it carefully, we already know that a hole is an absence of electron
so there is no charge but how will it still contribute to current? Hole current is also contribution of the
electrons. Electrons break the bond in the conduction band and replaces the vacancy available. So that
now vacancy is created in other place. This seems like hole is moving but actually electron is moving in
the valance band. Thus current due to holes is always in the direction of motion of hole i.e., direction
opposite to movement of electrons.
3) Electron always have greater mobility than hole because an electron in conduction band is free charge
carrier all the energy given is taken for mobility but a for a hole movement an electron in valence band
must break a bond and then move so some energy is lost. That is why electron has higher mobility than
hole.
Thanks all.(Any doubts?)
