what exactly is conduction band? (1 Viewer)

[leisl1990]

i under the suff about valence band and enerygy gap and how to explain its resistance.
but what exactly is conduction band?
and how do we relate the idea of conduction band and valence band to p type and n type semiconductor?
i know that it reduce the gap between valence and conduction band, but the logic doesnt make sense to me

 

[old.skool.kid]

I sorta had trouble with this as well, but its just a concept that helps us to understand the conductivity of insulators, semiconductors and conductors. Its not actually what goes on, you dont really have to understand it, you just have to remember it.

Band theory doesnt actually have anything to do with extrinsic semiconductors i dont think.

 

[obimoshman1234]

ok pretty much conduction band is the level where an electron will be free from the atom thus able to move freely amongst crytal.


p and n type refer to http://community.boredofstudies.org/showthread.php?t=190299 go to my post then go to website lol

 

[Glenjamin]

The band theory explains why semiconductors can conduct in some circumstances and the hole theory (with p and n ) explains how... im pretty sure thats right

 

[dolbinau]

If you have the success one book, 2008, go to the specimens ideas implementation question 23 they have a diagram of bands related to extrinsic semi conductors..It's pretty much the same but they say for N type "Impurities donate electron to conduction band" for P type "Impurities accept an electron from the valence band".

 

[Glenjamin]

Yeh for N type semiconductors according to the hole theory there are more electrons than there are holes which means there's spare electrons which means it can conduct better as more electrons are moving from the valance band to the conduction band

For P typle semiconductors there is more holes than electrons to fill them, which means electrons travel at a faster rate across the valance and into the conduction band, makes for better conduction, hope that helps

 

[Trebla]

i under the suff about valence band and enerygy gap and how to explain its resistance.
but what exactly is conduction band?
and how do we relate the idea of conduction band and valence band to p type and n type semiconductor?
i know that it reduce the gap between valence and conduction band, but the logic doesnt make sense to me

The idea of what a conduction band and valence band actually are goes into atomic orbital quantum theory. It's basically many discrete energy levels of electrons clumped together in a particular region of energy.

Here's a simplified (but not complete) explanation of it:

 

[DrFunk]

Just remember that the conduction is not a physical band. It refers to the energy level required for electrons to flow.
So in semi-conductors it refers to the energy difference between what the electrons have, and what they need to flow.

 

[dolbinau]

What is the highest energy level band?

 

[DrFunk]

There is no "band" but rather a way to think of energy levels. I'm not really sure if you have an electron with amazing amounts of energy if it does anything other than flow as current...
For the sake of HSC, the highest is conduction.