Whats the difference between a vacancy and a hole in semiconductor physics?

[lavster]

hi, I am reading my notes on semiconductor physics and this is a concept that is puzzling me - i always thought a vacancy and a hole were the same thing.

in my notes it says that

a hole has the same properties as a full band with one vacancy and so for consistency the hole must have...

(1) opposite k to the vacancy (where k is the wavevector) ie kh = -kv
(2) inverted energy (cf the vacancys energy) which occur wrt the chemical potential

etc

so is it different ways in describing the same thing? if so what's the difference on the two descriptions. Or are the completely different things? again if so, in what way?

thanks :)

 

[ZapperZ]

A vacancy is a "defect" in the crystal structure. A "hole" is a charge carrier stated in the band structure.

Zz.

 

[lavster]

so why is the wave vector etc opposite?

 

[PhaseShifter]

They're similar concepts, but a vacancy is when an entire atom is missing, rather than just an electron.