Actually what is the meaning of the holes

[tiantsai]

Hi,i am the new member of physics forum.Today we are having the solid state physics and semiconductors devices courses and the lecturer say something about electron in conduction band and the holes in the valence band in the semiconductor but we cannot really know what the holes is in the valence band...we thought the holes is the things that occurs when electron conduct or excited to conduction band and it is fix but my proffessor say that both electrons and holes can move...we so blur that times actually what is the meaning of holes...

 

[SpitfireAce]

I don't want to explain it b/c someone else could probably do a better job, but a "hole" in the valence shell is a positron

 

[ZapperZ]

Hi,i am the new member of physics forum.Today we are having the solid state physics and semiconductors devices courses and the lecturer say something about electron in conduction band and the holes in the valence band in the semiconductor but we cannot really know what the holes is in the valence band...we thought the holes is the things that occurs when electron conduct or excited to conduction band and it is fix but my proffessor say that both electrons and holes can move...we so blur that times actually what is the meaning of holes...

Holes are vacancies in the electronic energy state or bands.

Think of holes as air bubbles in water. The reason why they are useful is because you can then "renormalize" your word so that the background water becomes the "vacuum", and the bubbles now become the object or the matter in that new world. Now, all you need to do is consider the dynamics and the physical state of that bubble, and you have described your system. This prevents you from having to describe all that water instead (which is a lot more complicated since there's plenty of them).

So in the semiconductor system, in the conduction band (where there's a lot of empty states or holes as the "background"), you use the electrons as your "objects". In the valence band, where there's plenty of electrons as your background, you now use the holes as your "objects" to describe your system. When you do that, these holes now behave as objects with positive charge and mass.

Zz.

 

[kanzure]

Some links from my collection that are relevant to electron hole theory interpretations:

* Atoms, electrons and holes
* http://www.ee.technion.ac.il/orgelect/simple.htm
* Wikipedia page on electron holes

- Bryan