what is a positve hole (1 Viewer)

[tutor 2 success]

what is a positve hole

 

[alcalder]

When an electron leaves the lattice it leaves behind it a hole. So, the negative lectron leaves a positive hole. Because another electron will jump from further back in the lattice to fill that hole, you could say that the positive hols moves in the opposite direction to the electrons.

Does that help?

 

[*usernametaken*]

exactly. just imagine the holes are the negative of the electron or the inverse. therefore, they must be positive. if the elctron moves to the right, it leaves it's inverse behind. this means that this inverse electron or'hole has moved opposite to the electron, as an electron cant just jump into an occupied hole.

i hope that made sense

 

[James747]

I have a question - hopefully threadstarter wouldnt mind- but anyway,

How does the semiconductor carry a current? Like wut is the significance of the electron-hole pair in carrying an electrical current?

Thanks heaps,

 

[xiao1985]

Construction of p-type and n-type semiconductors I would guess. This enables loads of goodies (solar cells, transistors, amplifiers) to be constructed.

 

[alcalder]

Because of the structure of semi-conductors (4 valence band electrons) when one is excited it lkeaves behind a place where the atom would prefer to have an electron (hence a hole). Unlike metals where the electron is lost to the conduction band and moves along with the voltage provided, the current in a semi-conductor is due to electrons being excited to the conduction band leaving a hole which is filled by another electron excited into the conduction band, leaving another hole and so on.

Also, remember semi-conductor material is doped with other atoms that contain either 3 or 5 electrons in the outer orbit. It is the addition of these doping elements that make them P or N. These effectively add new holes or electrons that can be used in the valence and conduction bands.