All Questions
Tagged with electron semiconductors
13
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Carrier concentrations versus temperature and doping in Matlab
I am currently self studying structure of semi-conductors and I would like to make a graph in Matlab of the number of carriers as a function of temperature and doping. Let's say that I am testing ...
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0
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35
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How to calculate the diffusion length in modulation doping?
I have read a paper about an application of modulation doping in bulk thermoelectric materials. In this paper, the nanoparticles diffuse carriers into the host materials, and I want to estimate the ...
- 11
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44
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Reasoning behind the density of free electrons/holes being constant with respect to volume of a semiconductor material
Consider a silicon semiconductor material which is having a cuboid shape of dimensions \$2\times 2\times 1\ \mathrm{cc}\$, suppose the atomic density of silicon is \$10^{22}/\mathrm{cc}\$, so in all ...
- 103
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Majority Charge carriers and electron holes
Suppose I have an extrinsic semiconductor made of silicon and doped with phosphorous. Now, phosphorous has one more electron than silicon. After replacing one silicon atom, and taking its place, the ...
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301
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Mobility of electrons vs holes in semiconductors (intrinsic vs extrinsic)
I was reading my class notes and it was written that electrons are more mobile than holes because the effective mass of electrons are lower than that of holes. (μ=eτ/m*)
I checked online to find the ...
- 117
2
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211
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What does the fermi-level increase in reverse-bias?
Fermi-level tells us the probability of finding an electron at 50%. When you look at an energy band diagram in reverse-bias you can see the Fermi-level increases in the p-type semi-conductor. Why does ...
2
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66
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In an energy band diagram why is the valance band in the p-type have more energy then n-type?
I am having trouble understanding energy band diagrams. In an energy band diagram of a semi-conductor during equilibrium the valence band of the p-type is higher then n-type meaning electrons in the ...
- 21
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4
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Why does a p-type conduction band have higher energy then n-type conduction band in a p-n junction?
In an energy band diagram that represents the p-n junction (during equilibrium) the p-type conduction band has greater energy then an n-type conduction band. Why does the p-type have greater energy ...
1
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1
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374
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Does hole concentration fall below the intrinsic concentration, if Si is doped with pentavalent impurities?
If we increase N type doping in a pure Silicon then according to the equation
$$P_n=\frac{n_i^2}{N_D}\text.$$
Then mathematically, hole concentration is less than \$n_i\$, if \$N_D>n_i\$.
Why does ...
- 49
1
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1
answer
140
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Metal semiconductor Junction
As we know in normal p-n junctions is formed by doping on a single semiconductor so that material continuity is maintained which facilitates the movement of charge carriers between two regions. But in ...
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1
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182
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Electrons and Holes in a semiconductor
In an exercise I have an un-doped silicon I find that p=1.80e+11 ,n=6.60e+10 , should the numbers be more close to each other? (for example in GaAs I find 1.10e+14 and 1.60e+14)?? (also p number of ...
2
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484
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Semiconductor physics, effective mass calculations, band edge. vs. DOS vs cyclotron resonance
I am trying to understand effective mass for electron carriers in the conduction band as found in experiments. I am using the equations in a simulator. The simulator models power mosfets from -85C to ...
1
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1
answer
140
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When do the holes in semiconductor appear?
I'm trying to understand the concept of semiconductors, as far as I know whenever an electron moves it leaves a hole, so how can we say (for example) that n-type semiconductor has a majority of \$e^-\$...
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