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 affect it.
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weight of fully loaded RAM
I had read a post
Is a hard drive heavier when it is full?
It states, there is some difference in the weight of fully loaded hard drive and an empty hard drive due to different orientation of ...
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Is it viable or possible to make your own transistor?
Just wondering if it is possible/viable to construct your own transistor, not small like todays, but the same scale as the one created at Bell Labs.
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Donors/Acceptors in Metal Oxides
Can anyone explain to me why most articles describe chromium as an acceptor in titanium dioxide? In TiO2, titanium has the charge state Ti$^{4+}$ and oxygen has the charge state O$^{2-}$. When Cr ...
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In solar cells, do photons break apart electron-hole pairs, or create them?
Some sources say that when a photon hits the PV cell, it breaks apart electron-hole pairs. Other sources say that photons create electron-hole pairs. Can anyone explain which one is right? I've read ...
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Are $A$ and $J$ in Black's equation (for electromigration reliability of wires/interconnections) independent?
Black's equation is an empirical model to estimate the MTTF (mean time to failure) of a wire, taking electromigration into consideration. Since then, the formula has been getting popularity in ...
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2answers
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Would HgTe be a topological insulator?
In "Quantum Spin Hall Insulator State in HgTe Quantum Wells", researchers observed a 2D topological insulator by sandwiching HgTe between CdTe. Is the CdTe really necessary? Would Vacuum/HgTe/Vacuum ...
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Constructing Tauc Plots
How can we construct a tauc plot using data from the transmission spectra? How does one calculate the absorption coefficient for plotting tauc plots?
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Influence of the temperature on the ionization energies for impurities in silicon
Is there any dependence of the impurities ionization energy on temperature in silicon? I mean if there are any interactions between localized electron and phonons which leads to renormalization of ...
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DFT for bandstructure
Density Functional Theory (DFT) is not appropriate in predicting the band gap of the materials. However, which functional gives close value to the experimentally observed band gap of semiconductors? ...
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Producing electricity from all wavelengths of electromagnetic spectrum
Is it possible to produce electricity from all wavelengths of electromagnetic spectrum beside visible light ?Like using gamma rays or x-rays .
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How did the Bardeen-Brattain point-contact transistor work?
How did the Bardeen-Brattain point-contact transistor work?
What are the conditions under which a Schottky barrier injects minority carriers?
In a bipolar junction transistor the forward-biased ...
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141 views
How does current flow from the emitter, through the base and to the collector in a NPN transistor?
So, I understand that for a NPN transistor to work the emitter-base junction needs to be forward biased and the collector-base junction needs to be reverse biased. I understand how current flows from ...
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146 views
Photon Absorption and Emission: Conductors v. Semiconductors
I'm having a hard time understanding how photon absorption and emission in metals (conductors) compares to semiconductors. Obviously, in SCs, absorbed photons lead to electron-hole pairs and emitted ...
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If we connect a block of p-type semiconductor only to a positive terminal, will it become positively charged?
Connect the positive terminal of a battery to a piece of p-doped semiconductor, say, silicon doped with boron. Will the terminal pull electrons out of the doped silicon, or equivalently, inject holes ...
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Semi-conductors
Suppose there is a semiconductor with Fermi energy $E_f$ and that there are $N$ bound electron states.
I'd like to know why the mean number of excited electrons takes the form $$\bar n={N\over ...
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Estimation of the internal electric field strength in the pn-junction
I would like to compare my result in an order of magnitude. So, How can I estimate the strength of the electric field in a typical Si PN-junction?
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176 views
Tunneling v. Hopping
Can someone explain the difference between hopping and tunneling? The context I'm considering is conduction in semiconductors, specifically between impurity states within the bandgap. It's always ...
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fermi level in equilibrium and nonequilibrium situation
Why do the fermi level for electrons and holes coincide in equilibrium condition and why they separate as quasi fermi levels in non equilibrium situation?
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Fermi and Boltzmann distribution of carriers in semiconductor
What are the requirements for describing charge carriers (e.g. electrons) in a semiconducting material by
- Fermi distribution
- Boltzmann distribution
When do we apply the one or the other?
If the ...
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Working of a p-n junction diode when forward biased
If p-type semiconductor and n-type semiconductor of a diode are equally doped, and if the diode is forward biased, then holes will move toward the n-type semiconductor and electrons will move toward ...
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Electrical conductivity of an intrinsic semiconductor
On which factor does the electrical conductivity of an intrinsic semiconductor depend? It doesn't have an excess of charge carriers in fact, does it?
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Can electrons move through vacuum?
I studied that electronics is the branch of physics which deals with the practical applications of moving electrons through vacuum, semi-conductors and gasses. Can electrons move through vacuum?
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What limits the maximum attainable Fermi Energy for a material experimentally?
Either through doping or gating. What are some good terms to search for if I'm looking for some experimentally obtained values for particular materials? I'm particularly interested in what the limit ...
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Electron Relaxation/Polarization for and n-type Semiconductor
Please help me understand the following (general) statement, referring to electrons in a full valence band of an n-type semiconductor:
"An electron filling up the last empty state in the valence band ...
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Why does silicon have an indirect gap?
Is there an intuitive explanation as to why silicon has an indirect gap? I have heard that this can explained using pseudopotentials.
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1 Mohm Resistivity at cryogenic temperature for doped silicon
I would like to pick the correct doping of silicon to get 1 Mohm cm resistivity at liquid helium temperature of 4.2 K. The metal insulator transition implies that I need a very accurate doping. Are ...
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2answers
79 views
Carbon in the form of graphite a conductor?
Well, it happens a I have a glucose test strip (One Touch Ultra) which has three electrodes (Counter, Working and Reference) and I'm guessing this electrodes are made from graphite mixed with a ...
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Why is spectral sensivity of a photodiode expressed in A/W
Can someone explain me the meaning of the A/W unit of the photosensivity when reading a spectral response function of the wavelength characteristic of a photodiode?
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Semi-conductors and induced charge
Can a semi-conductor ( germanium or silicon) or a semi-metal ( graphite ) carry an induced charge ?
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Ionized Depletion Region, Why aren't those charged being excited?
Ok so I understand the PN junction, and how when 2 Semiconductor materials are placed together the Electrons will jump into the Holes near the junction creating a Negatively Ionized Atoms on the ...
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Semi-conductor band-gap and deformation potential
Submitting a semi-conductor to stress leads to a deformation in the energy-bands, roughly described by:$$H_{ij} = {\cal{D}}_{ij}^{\alpha\beta}\;\epsilon_{\alpha\beta}$$
$\epsilon$ being the strain ...
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How can a force be applied on hole? [duplicate]
What is actually a hole? Actually that is not a particle, but books are explaining that in semiconductors the polarity of Hall effect depends on the type of charge carriers whether it is p type or n ...
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Is it feasible to convert the energy of gamma-photons from gamma-emitting nuclear isomers into electrical power?
It is known that gamma rays emitted by nuclear isomers, naturally occurring or manufactured, carry huge amounts of energy. Co-60 for example decays into the isomeric state of Ni-60 by $\beta ^-$ ...
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How local is the stress tensor?
I am confused by the definition of the stress tensor in a crystal (let's say a semi-conductor), I don't see how it could be "more local" than over an unit cell. I know that in field theory the stress ...
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65 views
Carrier Electrons Generation and Recombination Time
When a Electron gets promoted to the conduction band from valence band (In generation) lets say for example in Silicon at room temperature.
Is there any way to determine (on average) how long it will ...
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Orientation in GaAs
I can't find the precise definition of what is the orientation of a GaAs lattice. Being the superposition of two fcc lattices (one of Ga, the other of As), I would think that it is the direction of ...
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In the diode equation, why the exponential $\exp$ and the ideality factor $n$ are there? What do they represent & what is their significance?
In the Shockley diode equation, why the exponential $\exp$ and the ideality factor $n$ are there? What do they represent & what is their significance?
I have to work on Solar Photovoltaics, and ...
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Why should the Fermi level of a n-doped semiconductor be below the one of a p-doped?
In a pn-junction, the difference in Fermi level between the p doped and the n doped regions causes the apparition of a built-in electric field at equilibrium. This electric field goes from the n to ...
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PN Junction Depletion Region
So it took me a little bit to understand this, but I want to make sure I have a few things right.
First of all, when a Crystal Structure with One side N-Doped, One Side P-Doped are in the same ...
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Regarding “Holes” in bands, and Photons
So from learning Band theory, and PN Junction and such, I've learned that photons are created when "holes" are filled in a band, and this is what can create light (Isn't this how LEDs work?)
Anyways, ...
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Exciton energy splitting in indirect semiconductor
Let's take an indirect bulk semiconductor and imagine the exciton that build up at the indirect gap. Since we have a bulk semiconductor we should find three p-like orbitals: $p_x,p_y,p_z$. Would their ...
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Piezoelectricity in GaAs
I am studying the piezoelectricity in Gallium arsenide (GaAs), $[110]$ and $[\bar{1}10]$ oriented. Piezoelectricity is usually described microscopically by a 3 index tensor, $d_{ijk}$ where
i,j and k ...
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2answers
435 views
Band Gap/Energy Bands in Semiconductors?
I think i've finally nailed down the Semiconductor Physics (Well the general part, whats and why's etc, as per my previous question)
Anyways there is one small part that confuses me, and thats BAND ...
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345 views
Explanation for transistor as amplifier
In transistor as an amplifier, we have NPN transistor (base in the middle and emitter and collector at the sides). The collector has electrons in majority because it is N-type. similarly, holes are in ...
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222 views
Resistance of Light Dependent Resistor (LDR)
Is there a mathematical expression relating the resistance of Light Dependent Resistor (LDR) with light intensity?
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endpoint detection in dry etch [closed]
i am working on the application of statistical tools to detect the endpoint in dry etch
Please if there is someone here, how could provide to me 5 data file (the intensity of wavelengths ) to apply ...
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Looking for a reference book, or book chapter to learn about piezoelectricity
I'm looking for an introduction to the treatment of piezoelectricity, specially in semiconductors emphasizing the dependence on the orientation of the unit cell and the interactive effects with the ...
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58 views
Explanation of NMOS processes
So, gate (poly-si + $SiO_2$) and $p^{-}$ silicon operate as capacitator.
But how are voltages and charges are applied? In order for inversion to occur, there should be charges formed in poly-Si, ...
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2answers
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Mobility in semiconductors
Good afternoon everybody.
I am reading on a book about semiconductor mobility. I have fully understood the definition, but I also noticed that often one talks about high or low mobility. My question ...
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255 views
Capacitance per unit area and CMOS case
In a modern 0.35μm CMOS processor, the gate oxide thickness is around 80Å = 8nm. This gives us a capacitance per unit area of $430nF/cm^2$
I am not getting how one gets this capacitance per unit ...
