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 Properly Discretize Semiconductor Continuity Equations
I am looking to perform numerical modeling of a MOSFET device and am wanting to better understand how to discretize the semiconductor continuity equations. The semiconductor equations consist of the ...
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Using Jacobi Method for Solving Full Semiconductor Equations
I am looking to perform modeling of a MOSFET device and have therefore been researching computational methods for how to do so. Quite often when solving the Poisson equation, the reader is pointed to ...
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Solid state devices, hole current [duplicate]
why do we consider hole movement as well as the electron movement in the total current term, the hole movement is the effect of the cause (electron movement), so how can they both contribute total ...
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Finite Difference Modeling of MOSFET Device
Does anyone know of any references for MOSFET modeling done using the Finite Difference Method that they could point me to? I understand the gist of the operation, namely using Poisson's equation to ...
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Why does an electron hole have a positive charge in semi-conductors?
From the link below, they explain when an electron in the valence band is promoted to the conduction band it leaves behind an electron hole. But in the case of the image below, we can see when Si is ...
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Is spin relaxation asymmetric in magnetic semiconductors?
I am considering photo-excitation in magnetic semiconductors (e.g. metal organic frameworks). The cartoon picture is like this:
where there will be a spin polarization in the conduction band since ...
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How is the number of charge carriers set free in an x-ray detector proportional to the energy of the incoming photon?
I'm a chemistry undergrad student and I've been doing some research into the ways light is generated and detected at different parts of the spectrum (for the purposes of better understanding practical ...
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Difference between the numerical values of the intrinsic carrier concentration $n_i$ in silicon
I've been working on the intrinsic carrier concentration for silicon, and if calculated with the formula
$$n_i = \sqrt{N_vN_c}\exp{\left(\frac{-E_g}{2kT}\right)}$$
taking the accepted values $N_v \...
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Semiconductor-graphene-semiconductor junction
In the literature, I've found Graphene-semiconductor junctions are treated as Schottky junctions. So by reverse-biasing a graphene n-semiconductor junction, we inject carriers into the graphene ...
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Why do dopant levels lie in the energy band gap of semiconductor?
Dopants create impurity levels in the band gap, this is what we were taught in semiconductor classes. And indeed that's what's seen in experiments (for example https://www.globalsino.com/EM/page2777....
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How can red LEDs still give a faint glow at a voltage of only 1.4V? [duplicate]
How can a red LED work at a voltage of only $1.4{\rm V}$? Red photons have an energy of $1.77{\rm V}$ if we use $\lambda = 0.7\mu\text{m}$ in the relation:
$$ E = \hbar \omega = \frac{2\pi\hbar c}{\...
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How does the Fermi level of graphene change if it is placed in a biased pn junction or in a plate capacitor?
I ran into a problem on which I can't really find any solutions in literature. I am looking at a Graphene sheet that is sandwiched in a biased pn junction (current flows orthogonal to the Graphene ...
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Graphene dispersion at Dirac points
After deriving the dispersion relation of graphene:
$$ E(k) = \pm t \sqrt{3+2\cos{(k_y \sqrt{3} a)} + 4\cos{\bigg(\frac{3a}{2} k_x \bigg)} \cos{ \bigg(\frac{\sqrt{3}}{2}a k_y \bigg)} } $$
how do I see ...
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Why would a depletion "layer" form in a PN junction?
I understand that electrons diffuse from the N to the P region due to the concentration difference. This diffusion of electrons creates an electric field opposing further diffusion.
What I don't ...
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Where can I read about excitons?
I'm having a tough time finding a good reference for excitons. I know next to nothing about them, and I'd like to find a good book/paper/notes that would introduce it in a slow, pedagogical way. ...