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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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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Definition of Hall's current
Dear fellow physicists!
I come to you with a question regarding the definiton of the Hall current.
The only sentence close to definition of this concept, I have found after extensive search on the ...
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Can a DC voltage excite a pure semiconductor (or insulator) from the valence band to the conduction band?
I have a question I am sticking around and can't find a satisfying answer. Say I have an intrinsic semidonductor at zero Kelvin (no electrons in conduction band). I apply a DC voltage across it. Can ...
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How is the energy per electron in Sommerfeld Theory interpreted?
I'm having a hard time understanding the way the energy per electron is calculated in Sommerfeld Theory. From the N.W.Ashcroft book on solid state physics it is done by first calculating the ground-...
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How a switching mixer works in this example circuit?
I am reading about lock-in amplifiers and came across this example circuit of a mixer:
You have one sinusoidal input signal $e_1$ with a phase $\phi_1$ and the local oscillator has a square-wave ...
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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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Interpretation of velocity in the de Broglie wavelength of an electron in a crystal
The de Broglie wavelength of a free electron is $\lambda = h/mv$ whre m is the free electron mass, and v is the velocity. Often in introductory solid state physics literature (review articles, lower-...
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Vacuum Tube Furnace Sealing Flange Design
I know this is not the best place to post this question, but in an effort to get the most prompt and direct response I chose this forum.
Can anyone suggest a good reference to the design parameters ...
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How would surface dipoles change the internal potential in a conducting sphere?
In the nanoscience literature, there is a model of semiconductor nanoparticle doping which ascribes the effect to surface dipoles shifting the absolute state energies relative to the environmental ...
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$\rm InP$ Mach-Zender modulator
I know how a Mach-Zender electro-optical modulator (MZM) works when based on non-linear crystals like LN. On-chip realization of MZMs is often done with $\rm InP$ that is a semiconductor. What is the ...
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Saturation region of common emitter BJT
About the saturation region of common emitter Bjt it's written that
In saturation mode both of the "diodes" in the transistor are forward biased. That means V(BE) must be greater than 0, and ...
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Why doesn't the voltage across this diode follow the voltage from the power supply?
Why the voltage across the Load resistor $R_L$ remains constant at 0.7 volts as long as the diode is forward biased?
Both diode and load resistor are parallel so the voltage across them should be ...
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The electric Field inside PN junction in reverse bias
In the unbiased PN junction the electric Field inside the depletion region is just due to the fixed charges inside it
But what happens in case of reverse
basing ?
In case of reverse bias the reverse ...
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When forming an n channel in an N MOSFET, do the pn junctions of the drain-substrate and source-substrate parts disappear?
When forming an n channel in an N MOSFET,, do the pn junctions of the drain-substrate and source-substrate parts disappear?
Here's what I expected:
When gate voltage (higher than threshold voltage) ...
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How can an electric current flow between the end of the channel and drain?
In my book, it explains why current can flow even if the channel ends:
The device still conducts: as illustrated in figure, once the electrons reach the end of the channel, they experience the high ...
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