How do you calculate carrier concentration in a doped semiconductor?

AI Thread Summary
To calculate carrier concentration in a doped semiconductor, the discussion centers on a silicon sample doped with 10^14 boron atoms per cm3. The user initially considers a formula for carrier concentration but questions its validity in relation to the doping concentration. They clarify that boron acts as an acceptor, leading to the relationship n + Nd = p + Na, where n is the electron concentration, Nd is the donor concentration, and Na is the acceptor concentration. The user seeks to determine the value of Nd and how it relates to the overall carrier concentration at 300K. Understanding these relationships is crucial for accurately calculating carrier concentrations in doped semiconductors.
becon
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I have a homework on Solid state device
the question is :"If a Si sample is doped with 10^14 boron atoms per cm3 then determine the
carrier concentration in the Si sample at 300K."[/b]

I thought that the concentration is calculate by
n = 2[(2pi*un*kT/h^2)]^(3/2)
is this right formula ? How about the Nd = 10^14 ?

thank you.
 
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I thought it wrong.
I have tried and solve it like : Boron is acceptor then Na = 10^14
by the charge neutrality relationship, n + Nd = p + Na
this is doped semiconductor, then n = Nd - Na and p = ni^2 / n
but what is the value of Nd ?
 
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