Questions tagged [semiconductor-physics]
Semiconductor physics is the branch of solid state physics that focuses on specific properties of semiconductors. It studies dynamics of different perturbations (mainly electrons and holes) in the semiconductor crystal and the ways to harness it in electrical circuits.
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How to calculate the diffusion length in modulation doping?
I have read a paper(dx.doi.org/10.1021/nl201206d) about an application of modulation doping in bulk thermoelectric materials, in this paper, the nanoparticles diffuse carriers to the host materials, ...
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Is the drift current of minority carriers negligible in the continuity equation?
When deriving the ambipolar transport equations for an extrinsic semiconductor under low injection, I have found certain discrepances between different references.
For instance, in Neamen's ...
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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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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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Phonon and the coupling to electrons
I am new to looking at phonons, especially in relation to their use in coupling to electrons.
Phonons can be defined as the treatment of vibrations in a crystal lattice. There can be different types/...
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Born–von Kármán (BvK) Supercell
I have come across in the literature Born–von Kármán (BvK) Supercell, which are described as a unit cell that is repeated periodically. However, say in a calculation that is derived using a BvK ...
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Intrinsic Fermi level in semiconductors
I heard that the intrinsic Fermi energy level always remains constant because it is an imaginary level assuming an intrinsic semiconductor.
However, at the same time, the Fermi level must also have a ...
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Why can you not create a LED equivalent by illuminating a colored plastic casing?
I would first like to apologize if this is a dumb question.
I understand the physics of color sufficiently well. You have an incoming photon that intercepts an electron on the atom, the electron gets ...
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Reverse current
I'm getting started with electronics and couldn't help but wonder about this. When the PN junction diode is reverse biased, P connected to the negative terminal and N connected to the positive ...
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Why the number of minority charge carriers not increase when we put a potential is reverse bias in a diode?
When we put a diode in reverse bias, should not the electrons coming into the p side cross the barrier to the n side. We know that they are minority carriers here but why is their number less in spite ...
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NPN BJT transistor large signal model
which of the following is valid forward active mode large signal model of npn bjt transistor ,here a),b) similar and c),d) are similar I want to know a) or c) which of them is best and valid ...
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Net electric field inside a photovoltaic cell under load
In a photovoltaic cell is basically a pn-junction where free electrons are created by a photoelectric effect.
Now I am interested to understand the electric field inside the depletion layer for ...
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Notation for intrinsic charge carrier
What exactly is $n_{\textrm{i}}$? It is said to be the intrinsic charge carrier, but for pure semiconductors, $n_{\textrm{h}} = n_{\textrm{e}} = n_{\textrm{i}}$, is $n_{\textrm{i}}$ not the sum of ...
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Valence band in silicon (semiconductors)
I recently learnt that in a solid lattice there are many energy levels which are so continuous that they look like bands...
In silicon' valence band,there are those millions of 3p energy levels with 2 ...
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How does photovoltaic effect work?
If I understand it correctly, due to diffusion and something like a concentration gradient, a gate layer is formed at the PN junction (at P there is more space=holes, at N there are a lot of packed ...
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