Semiconductor Definition and 400 Threads

Hello. Does anyone know a good book explaining light and semiconductor interaction? Namely, the processes that take place inside the material.

I'm trying to understand recombination losses and ways to improve and reduce them in a standard crystalline silicon cell? I've been looking online for a while now but can't find any simple explanations. I understand recombination occurs when a conduction band electron loses energy and...

What is the difference between solid-state (SS), semiconductor and gas lasers? I know SS lasers are optically pumped (generally), while semiconductor and gas lasers are electrically pumped (laser diode). The active mediums are also unique. Beyond this though, I'm not entirely sure about any...

How is a top gate used to change electron density in 2D semi conductors? I get the principle, you are just shifting the chemical potential by some voltage so that there are more or less electrons in the specific bands. But how is it physically done? Thanks.

Homework Statement Estimate the carrier density and mobility of a semiconductor with a Hall coefficient of ##R_{Hall} = 7*10^{-5} m^3C^{-1}## and a conductivity ##\sigma = 200 (\Omega m)^{-1}##. Is the semiconductor n-type or p-type? Homework Equations ##R_{Hall}=\frac{1}{ne}##...

So I'm doing up a physics report but i got stuck on this question :( Q: Explain the factors that influence the spectral linewidth of the emission spectrum. i'm guessing that it has something to do with the types of elements used in doping the semiconductor? but i don't know how the theory part...

So I've been studying electrons behavior in a semiconductor superlattice and I am currently analyzing the negative slope for the drift velocity against electric field. This is where negative differential velocity (NDV) takes place. I understand how NDV leads to negative power, but I can't quite...

Based on my research the effects of the holes, electrons, acceptor and donor concentration is telling you the direction of the polarization and the conventional sign of the electric potential generated. But up until now, i don't know what is the best material to used for piezoelectric material...

Please explain me. I don't understand what is quasi fermi level f(E) and fermi energy Ef. For example (GaAs) at the room temperature (T=300K) Eg = 1.42 eV; (energy band gap) mc = 0.067 me; (effective mass of electron in conduction band) mv = 0.45 me; (effective mass of hole in valance band) kT =...

Unlike Ohmic resistors the resistance of a semiconductor decreases with temperature...or not. Can a fragment chipped off a diode or some random IC be used to measure this with a multi meter??

Suppose I have an n-doped semiconductor and want to measure the electron concentration in the conduction band as a function of temperature. How would I go about doing this by measuring the Hall coefficient as a function of temperature, given that I don't know the electron and hole mobilities...

Hi, I have been using Semiconductor Parameter Analyzer Agilent 4156B for 1 year. Since a month it is malfuntioning. I am not getting the required IV for my Resistive Random Access Memory (RRAM) devices. To confirm, I checked my devices using some other lab's analyzer which proved that there is...

Hi, Lately, I've been trying to compare and understand conduction properties of metals and semiconductors. However, there are two question on my mind that I'm still trying to figure out. Maybe someone here might be able to provide some clues. 1. It is known that a linear increase of the...

Homework Statement Hi all, I'm currently working on a Hall effect lab in which I analyze a p-type sample of germanium (I know it's p-type because I observe a hall voltage inversion point around 350 K which can only happen for a p-type sample). From the Hall and resistivity data I can obtain...

Typically, I should ask an expert in photolithography about this, but, there are barely photolithographic engineer in our department so I decided to ask experts here. Where do you usually buy a reliable photoresist, what company in particular?

Homework Statement Let’s introduce an imaginary atom which can replace the silicon atom and generate one mobile electron. What is electron density when all silicon atoms are replaced by this imaginary atom Homework EquationsThe Attempt at a Solution I have tried looking for a formula to...

How do you go about calculating electron densities, especially when impurities are involved?

Hi there Im working in a solid state lab I have a semiconductor, let's say 'AB' nowim trying to dope it with a new element 'C' to form 'AB(1-x)Cx' im using bridgman technique for this purpose,,,that is heating all the ingredients together now the problem is that the element C sublimates before A...

The book I'm reading is discussing the physics of semiconductors. I'm having a hard time understanding a passage in section introducing n-type semiconductors. (Phosphorus is used as the impurity) The book says: "At normal operating temperatures, this extra electron breaks its bond with the...

Hello pf Is the effective mass dependend on the donator atom in a semiconductor? In our experiment we have calculated the effective mass in a germanium semiconductor, doped with an unknown atom. It is 0.39m_e. From the internet we know that the effective mass is 0.33m_e. Is our result...

I am interested in simply simulating in MATLAB or an open source software, the following qualitative explanation of the band theory. I want to show to an undergraduate course maybe a simple applet with the difference between semiconductor (Si) and insulator (Diamond for example) . do you have...

Hi, How can I prove direct band gap property of a Transition Metal Dichalcogenide electrically and optically through experimentation? I can use PL measurements to prove this for optical band gap. Is there any other equipment or technique to prove this? I can not use ARPES because channel length...

Hi, Why is it important when creating a 2DEG that the fermi level lies in-between the 1st and 2nd energy levels? As shown in the attached image. Thanks Jamie

Homework Statement Can anyone explained to me the factor of 2 in the equation for the intrinsic carrier concentration? Homework Equations ni is proportional to exp(-Eg/2kT) where ni is the intrinsic carrier concentration, Eg is the band gap energy, k is Boltzmann's constant, and T is...

Please check the following questions. Steady state of semiconductor w.r.t excess carrier. 1. If we shine photons on semiconductor and then turn the light off, semiconductor is not under the steady state condition. (it is under transient state since excess carrier concentration is decreasing)...

What is the difference between a "good" and a "bad" oxide?

Homework Statement This isn't actually a homework question, but in my semiconductors textbook, the following equation has been given: E_f = E_g - k_BTln(\frac{n_0}{N_d - N_a}) This is for the limiting case Nd>Na>0. I got a little confused as to where that equation has come from. Homework...

(1) (2)(3) (4) (5) we can find Equation (5) by dividing po by n0, and write an equation with respect to Ei. However since equation (3) is a special form of (1) and (2), [when Ef=Ei] we can obtain equation (5) from any arbitrary Ef. However, since eq (5) consists of constants only, it will...

http://ecee.colorado.edu/~bart/book/book/chapter2/ch2_6.htm#2_6_2 equation (2.6.24) we have this equation for fermi level, but I wonder how this works though? In the lecture, we assumed Ec=Eg and Ev=0 to get E_gap/2. but I wonder how (Ec+Ev)/2 actually gives E_gap/2 instead of Ec-Ev=Eg

Homework Statement A sample of germaium has an acceptor concentration of Na=10^17 and a donor concentration of Nd=0. Calculate the intrinsic carrier concentration, majority carrier concentration, and Ef-Efi. Use T=400 Homework Equations No*Np=ni^2 Nv=Nv*(T/300)^3/2 Nc=Nc*(T/300)^3/2 ni^2=Nv*Nc...

Homework Statement Si atoms get doped inside GaAs to a concentration of 1.5*10^8 . Assume that the silicon atoms are fully ionized and that 35percent atoms replace gallium and that 65% of the added atoms replace arsenic t=300k Fnd the acceptor and donor concentrations Calculate electron /...

Homework Statement The question is in the picture attached. When Na=0, that means the acceptor concentration(i.e. open holes?) is zero? Homework Equations (Nd-Na)/2 + sqrt((Nd-Na/2)^2+ni^2) (Na-Nd)/2 + sqrt((Na-Nd/2)^2+ni^2) The Attempt at a Solution Solving for Nd=10^8: majority carrier =...

I'm not good at English. I'm a undergraduate student. I'm interested in this research. I'm interested the simulation part but I don't know how to start. Please guiding me how to simulate method or program did they use on paper. " A Theoretical Study on Van Der Pauw Measurement Values of...

Homework Statement In my book ,I found this line which says ,"The collector current comprises two components-the majority and the minority carriers .The minority-current component is called the leakage current and is given the symbol ##I_{CO}## .The collector current, therefore is determined in...

What is Dielectric confinement effect?. or could you advise me literature about this? Thank you.

For Mass action law to hold for extrinsic material in equilibrium, If n goes up and p goes down for an N-type material then overall carrier concentration is the same (equal to ni_square). So why does an N-type material conducts better than a an intrinsic semiconductor (presumably they have same...

Can someone give me a clear, nonambiguous definition of the fermi level in a semiconductor? Is it the energy of the highest occupied state, the chemical potential at T=0 or what? I don't think it is the first since the fermi level is typically put midway between the conduction and valence band...

Hi, I understand that a n type doping will increase the number of electrons, and those electrons will go to the conduction band since the valence band is already filled. I don't exactly understand the effect on the bandgap. Thanks!

I know we can shift the fermi level by doping the material with other elements. In case of semiconductors doping with the pentavalent or trivalent will change the fermi level. But my question is ''can we shift the fermi level, without altering the position of valence band and conduction band?"...

Why is the conduction band state s-type and the corresponding valence band state p-type?

Can anybody explain my what is the origin of this forbidden gap? I mean how it was created and what is the physics behind this issue?

I am finishing my degree in Mathematics and will be enrolling into a Mathematical Physics program. My goal is to work with Semiconductors. Is this possible to find software that chip design engineers use? I would like to design my own chips with software to build a basic understanding that...

Good day!, today, i visited an Institute about Semiconductor devices, One characterization device (Reflectance Spectrometer) which used to determine the reflectance of the semiconductor materials. This device used Semiconductor detector to detect the reflected light from the sample, but I'm...

I'm looking to find out what is degenerating in a semiconductor that is being bombarded with beta particles. I know in the low energy tritium beta cells. There is less degeneration because less energy. I know that current is formed by the beta particle making pair holes in the mobile band. Is...

Hi Guys, i want to fabricate semiconductor p-type and n-type material and i want it to combine to make a p-n junction diode, but i don't know how to combine or merge the two, (my materials are thin films) I'm thinking to solder it but I'm afraid that it will break, or distort, or I'm thinking to...

Is the no. of electrons on a brand new unused and untested harddisk is different from no. of electrons on a used hard disk completely filled with data. i mean will there be even a change of one electron? Please consider the following points before answering: 1- Does all the electrons from a...

Hi, I am working on CdZnTe detector. Can anyone please explain the function of bias resistor in radiation detector setup & how to select an appropriate bias resistor?

Why is a slab of semiconductor used instead of just a basic resistor. The charge would be pushed to either side by the magnetic field in the same way, would it not?

I was wondering if anyone knows the relationship with temperature and frequency tuning in wide bandgap semiconductors. I just want to know why wider bandgaps have higher temperature tolerance and why does that mean high frequencies can be achieved? Explanation with formulas would be great!

Homework Statement (a) Show law of mass action. (b) Find dopant concentration and hole concentration.[/B] Homework EquationsThe Attempt at a Solution Part(a)[/B] Bookwork. Part(b) Letting the doping concentration be ##D##, we have: D = n - p For ##I = n_{intrinsic} = p_{intrinsic}##, we...