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Tagged with semiconductor-physics fermi-energy
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Fermi Level Shift in PN Junction
The image below shows the Fermi level shift of the PN junction when the potential of the N region is positive with respect to the P region. My textbook (Semiconductor physics and devices by Donald A. ...
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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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Thermal Properties of the Free Electron Gas: Explanation of the $N$-particle systems and averaging over all $N$-particle stationary states
I have a master's degree in engineering and am trying to study more detailed topics in solid-state physics on my own.
I have difficulties to understand the (2.38)
$$P_{N}(E)=\cfrac{e^{-E/K_{B}T}}{\sum ...
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Depletion regime in MOS capacitor
(I originally asked this in Electronics SE, I was redirected here as this was a better place to post my question)
I was watching a video lecture recorded by my Uni prof, where while dealing with the ...
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Apparent contradiction in the definition of Fermi-level
The fermi level in an intrinsic semiconductor is defined as $$E_F = (E_c + E_v)/2 + kT/q \ln (Nv/Nc).$$ From this equation, the position of fermi level is exactly at the center of the band gap at 0K.
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Is the Fermi level taken to be (approximately) constant, i.e. equal to the Fermi energy, in semiconductor physics?
I have been reading Neamen's "Semiconductor Physics and Devices" Chapter 3. He derives in Eq. (3.79) the Fermi-Dirac distribution function
$$f_F(E) = \frac{1}{1 + \exp(\frac{E-E_F}{kT})}, $$
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Chemical potential vs Electrostatic potential in semiconductors
In Semiconductor Physics, the bottom of conduction band $E_C$ is treated as the electrostatic potential. This energy level is typically used to express the carrier concentration in terms of the ...
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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 is Fermi energy considered most probable energy that electron posses in solids?
It can be seen in graph that probability of electron occupying a energy level below $E_{f}$ is $>\frac{1}{2}$, then why it is said that Fermi energy is considered as most probable energy that ...
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How many $\rm eV$ near Fermi level are involved to the conduction of carriers? For metal and degernerated semiconductors?
How many $\rm eV$ near Fermi level are involved to the conduction of carriers? For metal and degernerated semiconductors? Someone say about ± 5 eV, but I cannot find any references to support.
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Can the lifetime of an electron in the conduction band be calculated?
We know that in a semiconductor in every instant of time some electrons get excited from valence band to conduction band and some electrons are deexcited from conduction band to valence band. In this ...
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