All Questions
Tagged with electricity semiconductor-physics
22
questions with no upvoted or accepted answers
2
votes
0
answers
177
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Van der pauw method for an isolated hole
Van der pauw method is a way to measure the resistivity of a material with arbitrary shape while it meets some specifications ( being homogeneous and ...).
One of the conditions is that the sample ...
- 322
2
votes
1
answer
718
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How to check the ohmic contact to the film?
I have a thin semiconductor film deposited on an isolating substrate. I would like to check different metals to find out do they form the ohmic contact or Schottky barrier.
What is the best way to do ...
- 21
1
vote
0
answers
71
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How do I calculate the standard uncertainty? Task on determination of energy gap width of semiconductors
I am creating a report for my physics class and all I have left to do is calculate the standard uncertainty for this formula.
$$ \ln \left( \frac{R_{T}}{R_{\infty}} \right) = \ln \left( R_{T} \right) -...
- 111
1
vote
1
answer
287
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Is there a potential difference across the bulb after current passed through a diode?
I understand that voltage can exist without current so what I want to ask is will there be a potential difference across the bulb(situated after the diode) when a batteries supplied energy through a ...
- 113
1
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0
answers
1k
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Differences in conductivity as temp rises for intrinsic vs extrinsic semiconductrs
For a doped semiconductor, near the end of the extrinsic temp region due to heightened effects of lattice scattering conductivity goes down "temporarily" (temperature wise).
What happens to the ...
- 11
1
vote
0
answers
84
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How does Passivation in Mercury-arc-valve cause "diode" behavior
Does passivation of lead anodes cause them to become semiconductors?
Or even become diodes (eg. a p-n passage)?
How does this work on an atomar level?
This question has been risen by trying to ...
- 243
1
vote
1
answer
216
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Simulate Band Bending and Band Alignment in Semiconductors
Are there softwares (simple ones preferred) where we can simulate the band alignments and band bending of a p-n junction, where we can vary properties of the junction materials such as carrier ...
0
votes
1
answer
60
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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 ...
- 21
0
votes
1
answer
58
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Current Amplification in Common Base Transistor
How does a common base transistor amplify current if a small part of its emitter current gets divided into base current and the rest goes to collector current? If the input signal is applied to the ...
0
votes
1
answer
651
views
Why is generation rate equal to recombination rate in extrinsic semicondcutor?
The mass action law states, that the product of electron concentration and hole concentration is equal to the square of the intrinsic carrier density. That applies to both intrinsic and extrinsic ...
0
votes
0
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49
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Where does the drift current in a pn juntion come from?
I know I know. There are around 4 similar questions on here, but they do not properly answer my question.
I'd like to know where the drift current in a pn juntion (no bias) comes from. From what ...
- 23
0
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0
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25
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Do you get correct graph of transfer characteristic, if you take +ive Vds(constant) value instead of -ive. As mostly CNTFETs are p-chnl FET
I'm studying transfer characteristic curve of CNTFET to get value for mobility, S.S, etc. According to my basic background knowledge, NMOS curves lie in the 1st quadrant. While for PMOS they lie in ...
- 11
0
votes
1
answer
31
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Will there by a voltage drop in the p-type in the diode?
Assume we have a pn diode, and we have forward bias so that we get electricity through the diode.
My question:
Will there be a voltage drop over the p type? (NOT the depletion laywer, but the rest of ...
- 199
0
votes
0
answers
24
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Understanding a charged isolator
If an isolator gets charged (e.g. by rubbing it to an other isolator), it can get charged. If it is negatively charged, I would expect the additional electrons to be in the conduction band, so that ...
- 171
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0
answers
35
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Is activation voltage the sum of voltage required to collapse depletion layer and band gap energy?
Is the energy released when an electron moves from the valence to conductance band states the activation voltage or is activation voltage the energy required for electrons to overcome the depletion ...
- 31
0
votes
1
answer
74
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How do electrons exit LEDs? Aren't they in the valence energy state?
If a conducting electron reduces to the valence band in an LED, where does it get the energy to go back to the conductance band upon leaving the diode so current can flow?
I'm confused as to how ...
- 31
0
votes
1
answer
238
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Electric fields and electric potentials in semiconductors
The zener diode is heavilier doped than a normal diode , that is why its depletion region is smaller than the delpetion region of a normal diode and that is why the electric field is very strong.Zener ...
- 165
0
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0
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76
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Zener diode electric field working principle
Well I recently saw a video from khan academy about zener diodes.This video was suggested by another member of Stack Exchange Physics who I thank him very much . But I didnt understand some things:...
- 165
0
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0
answers
37
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How am I obtaining silicon with resistivity proportional to the number of conduction electrons?
The resistivity of silicon is given by
$$\large\rho=\rho_0e^{\Large{{\frac{E_g}{2k_BT}}}}$$
and the number of conduction electrons in a semiconductor conduction band is
$$\large n_{\text{...
- 4,607
0
votes
1
answer
500
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Quasi-fermi levels in a solar cell?
I was wondering, if my fermi levels splits up due to n and p type doping into two fermi levels, one for the p type one for the n type, and now due to light radiation my fermi levels split up into 2 ...
user85397
-1
votes
1
answer
41
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Isn't heating insulator enough for sufficient electrons to escape valence band and conduct electricity?
Diamond has about 5.5eV of energy gap, So If I heat diamond it will get atleast 1J energy which is enough to excite about 10^18 electrons, But Diamond still not conduct electricity, Why?
-1
votes
1
answer
183
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How does the solar cell work?
I know that a solar cell consists of a transistor (NP). First step it creates a barrier between the n type and the p type junction. Then the sunlight (i.e, the photons) supply energy to the electrons ...
- 21