All Questions
Tagged with semiconductor-physics chemical-potential
31
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How does the Fermi level of graphene change if it is placed in a biased pn junction or in a plate capacitor?
I ran into a problem on which I can't really find any solutions in literature. I am looking at a Graphene sheet that is sandwiched in a biased pn junction (current flows orthogonal to the Graphene ...
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Change in internal chemical potential of electrons in the 2DEG
I was reading about quantum capacitance and came across the following formula:
$$\Delta \mu = \frac{N}{\rho}$$ where N is the number of electrons moved from the metal to the low-density-of-states ...
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For intrinsic semiconductors, is the gap Energy equals $E_c-E_v$ or $E_c+E_v$?
So I have a problem with the intrinsic Fermi Level because by definition it is in the middle of the gap energy, and knowing that Eg=(Ec-Ev), we should have Ei=(Ec-Ev)/2.
But when we follow the ...
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Temperature dependence of chemical potential in a semiconductor
My professor just uploaded the following two foils:
and
Now I understand that if temperature increases we have some electrons in the conduction band and some holes in valence band, which would (I ...
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Definition of Fermi level
In wikipedia article, there is following sentence.
The Fermi level of a solid-state body is the thermodynamic work required to add one electron to the body. It is a thermodynamic quantity usually ...
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Is the Fermi level taken to be (approximately) constant, i.e. equal to the Fermi energy, in semiconductor physics?
I have been reading Neamen's "Semiconductor Physics and Devices" Chapter 3. He derives in Eq. (3.79) the Fermi-Dirac distribution function
$$f_F(E) = \frac{1}{1 + \exp(\frac{E-E_F}{kT})}, $$
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Intepretation of the Fermi Dirac distribution graph [closed]
Is there a significance or an important interpretation of the fact that the plots in the Fermi-Dirac distribtion graph, all intersect at the point with coordinates ($\epsilon_F$,$\frac {1}{2}$)?
https:...
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Proof that Fermi level is constant throughout a system in thermal equilibrium
The explainations I saw:
The one I was referring to in this question. I described why I find this explaination not satisfying in the question.
Consider $2$ systems in contact. The rate of particles ...
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Why does the bottom of the conduction band correspond to the potential energy of an electron?
While proving that Fermi level is constant throughout any system in thermal equilibrium, all the books I saw the proof in (for example, Sze and Shur) assume the following:
the bottom of the ...
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Where do the electrons that are filled up to the fermi level above the valence band go?
Many questions have been asked on this topic, but this has never been answered satisfactorily. Yet I want to give it a shot. Fermi Energy represents the energy level achieved when all the available ...
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Why does the depletion region in a reverse biased diode grow?
From what I understand, at the pn-junction of a diode, electrons diffuse from the n-region into the p-region until the resulting electric field grows large enough to stop any further flow of electrons....
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Is Fermi level always constant?
Let us imagine a heterojunction with one side called A and the other side called B. Both A and B are n type materials with different doping levels. A has a higher conduction band energy than B, but B ...
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What happens to the Fermi level of a metal/semiconductor under bias?
When a metal/semiconductor junction is placed under bias, the Fermi level of the semiconductor shifts horizontally up or down increasing or decreasing the potential barrier. I was wondering if this is ...
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Doubt about interpreting Fermi level in semiconductors
Before I say anything, I know there's already a bunch of questions about the Fermi level in semiconductors on this website but I don't think my doubt in particular has been addressed before.
From what ...
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What is the chemical potential in case of semiconductors?
What the chemical potential physically means? In case of semiconductors how is it relevant? What is the difference between chemical potential and fermi energy in case of semiconductors? What is the ...
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