Talk:Electron hole
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Unfortunately, while this explantion is taught in enginnering schools it has a major problem. Specifically, it violates conservation of charge. That it does can be shown by the Hall Effect.
In short, the electron gets promoted and "leaves a hole behind". Then, presto chango, this hole "acquires" a positive charge that can be detected by the hall effect. The hall effect is detecting something, no doubt about that. But that "something" is definitely not a "hole" or a lack of electron. Its something with a charge moving with a velocity.
Does anyone *really* know how this stuff works?
The positive charge comes from the nuclei in the crystal lattice. The lattice is initially neutral:
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then an electron is dislodged from a site, leaving a localised negative charge at one location and a localised positive charge at another
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The localised positive charge is the "hole", and it moves when the electrons near it move in the opposite direction. Here the hole moves left:
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A hole is in some sense imaginary, it just consists of an excess of protons compared to electrons. But it turns out that to describe this excess as a particle with mass and velocity is very useful theoretically. -- Tim Starling 23:39, Feb 3, 2004 (UTC)
Do holes repel each other? If they really behave like particles they would. For instance, a metal sphere with a few electrons missing will apparently have all of its charge (positive) migrate to the surface of the sphere and evenly distribute itself. This is confusing to me, though, since the electrons are repelling each other. I would expect them to spread out as far as possible, even if there are less electrons than protons. This could be seen as holes spreading out as far as possible, but they are not real particles, and it is not obvious how they would repel each other. Can someone explain this and include some type of explanation in the article?
Likewise, in semiconductor thermoelectricity, it makes sense that excess electrons would diffuse from a hotter region to a colder region, because of their thermal energy, but it is not as obvious why holes (in a p-type semiconductor) would migrate away from the hot region. But they do. (I think.) - Omegatron 13:49, Apr 6, 2004 (UTC)
This material was added to a duplicate page. Is any of it useful here?
Hole is a quantum-mechanical counterpart of an electron. It arises out of the solution of Schrodinger's equation for a periodic potential, which exists inside a semiconductor crystal. One can think it as a 'fictitious' particle or just 'an absence of electron' which is able to carry the current in a semiconducotr just in opposite direction to that of electron current. Quantum-mechanical considerations show that though it behaves just like a positively charged electron, its mass is little higher than that of an electron and consequently it has lower mobility. Naturally, devices where holes are majority carriers, is slower in operation than the devices having electron as majority carriers.
The important thing to remember is that a hole is not a positron, which is a fundamental particle having exactly same features as electron but opposite charge.
Rmhermen 21:19, Jul 16, 2004 (UTC)