depletion Definition and 67 Threads

Hello, I'm testing about burnable poison depletion with mcnp6. I'm using m1 92233.82c -7.91619E-01 90232.82c -8.75802E-02 8016.82c -1.20800E-01 for fuel and m12 64152.82c -1.39023E-03 $ gd-152 64154.82c -1.53529E-02 $ gd-154...

I was having a conversation with a coworker and this question came up: is there a program like ORIGEN (or maybe even ORIGEN) to run decay calculations in reverse? It's a relatively easy process to start with a given quantity of an isotope (e.g. U236), run it through a program such as ORIGEN...

Hello there, I have derived the expressions for electric field and potential to be the ones above, then for continuity at ##x = 0## I set the electric fields and potentials to be equal to yield the expressions: $$Sx_p^2 = Kx_n^2$$ $$V_{bi} = V_n - V_p = \frac {q}{3\epsilon} \left( Sx_p^3 +...

I do not understand why that is the case. Is there any intuitive explanation for it? Thanks

I would like to ask about the behavior of a MOSFET as a capacitor, particularly at the onset of inversion/weak inversion - see Fig 2.6(c) At this stage in Fig 2.6(c), there is positive charge at the gate metal/poly contact, then an insulator oxide and then negative ions (positive holes have...

My question for now is as follows: Why does a high doping concentration causes a decrease in the thickness of depletion region. Any help will be highly appreciated! Thanks a bunch Regards!

I am running some depletion calculations and have noticed odd behavior when keff is much greater or lower than one in the number of absorption's taking place on the outside the reactor. MCNP seems to be deleting the neutrons after it has reached the number of fissions required for the power...

In a diode, we have N side, P side, and a depletion region, made of positive and negative charged sides. N side and P side of the diodes are neutral charge. In N side there are free electrons. In the positive charged side of the depletion region, there are positively ionized atoms that "lack"...

Hi, Lately I've been reading about a lab exercise in which Planck's constant is estimated using LEDs. Every procedure I've encountered states that the energy of an emitted photon (and by extension the potential across the semiconductor's band gap) is equal to the threshold voltage multiplied by...

Homework Statement Homework EquationsThe Attempt at a Solution I think before getting the steady state, after doping there are more electrons in n-region and there are more holes in p-region, so the more electrons go towards the p-region and more holes go toward the n - region. Consequently...

Hello, I've been researching photovoltaics and I've seen some articles which state that the width of the depletion layer is not equal on both sides on the pn junction. i don't understand why this occurs I've tried to research why and how this happens but have been unable to find an answer.

In an unbiased p-n junction, how does increase in doping affect the width of Depletion Region? I read somewhere that width decreases as increase in carrier concentration leads to more recombination of majority carriers with oppositely charged ions of their depletion regions leading to a...

in a P-N junction diode, in an equilibrium state, a depletion layer forms in the surface of contact of N type and P type. But the problem is, this layer is formed by diffusion of electron to a lower electron density zone. Why does it always have to form right in the contactt surface? when...

The depletion layer is formed by the movement of electrons from the n to p side and holes from p to n side of the diode. The layer consists of positively charged donor ions close to the n side and negatively charged acceptor ions close to the p side. When in equilibrium,the barrier potential...

I am having some trouble understanding the physics behind the formation of Schottky Barriers. According to the convential theory, the idea is that for an n-type semiconductor the electrons in the conduction band can lower their energy by filling empty states in the metal. This in turns creates a...

Homework Statement I'm doing a course in solid state electronics and we just started PN junctions etc. I'm a bit confused. So here is what I know so far: Initially the P and N regions are separated by a a PN junction. At 300K as the acceptor atoms on the P side and donor atoms on the N side...

The electric field ...(1) by saying that ...(2)I tried to integrate equation (1) from r2 to r1 but could not get equation(2). Any suggesting. Thanks

Hello. I've learned that in PN junction, forward-biasing on it pushes holes in P-type and electrons in N-type toward the junction so depletion width is reduced. Is it due to that in N-type side(P-type side), pushed electrons (holes) are recombined with holes (electrons) in depletion zone? And...

Hello. I've learned that in PN junction, forward-biasing pushes holes in P-type and electrons in N-type forward junctions so depletion width is reduced. Is it due to that in N-type (P-type), pushed electrons (holes) are recombined with holes (electrons) in depletion zone? And what is true...

If only 14% of the total solar emission is in the UV region, why is ozone depletion a cause for concern. Considering that only a small fraction of the sun's total radiation reaches earth.

why do electric field is zero out side of depletion region?

Hello, I read a derivation for the width of the depletion region W in "SEMICONDUCTOR DEVICE FUNDAMENTALS" by Robert F. Pierret in which at one point it says: http://imageshack.com/i/ipbgKsK9p Here again for better readability: x_N = \sqrt{\frac{2 K_S...

Here's something I can't get my head around: Take a diode (can be schottky, p-n etc) where the predicted depletion region is larger than the actual thickness of that layer will ever be. What happens? I've seen papers where its assumed that this curtails the built in potential. But it sounds...

Homework Statement Consider an n-type Si (Eg =1.1eV, ED=EC, εr=11.8) with a bulk doping density ND=1×1017cm-3, a density of acceptor type surface state 1×1014 cm-2 and these states are at the middle of the band gap. Evaluate the amount of: a) band bending b)depletion layer thickness c) density...

Why we are not writing Cgs Cdb in depletion mode nmos here why no Csb in bottom nmos Can somebody please explain how to write which components of Cload or provide some links from where i can understand it better thank you, this picture is from...

Hello every one, Here in below figure we can see an ohmic contact formation between a metal and n-type semiconductor . Here how the N-type semiconductor bands are banded upward ? and what type of depletion charge exists there ?

Hello, I am a graduate student attempting to run evaluate the depletion of a ceramic film attached to the moderator-side of the fuel clad. I am having some issues with my MCNP syntax/code and I was wondering if one could assist. My input file is attached. I am not looking for someone to...

Hi, I'm studying the p-n junction and I'm a little confused about the depletion layer that forms. I understand how electrons and holes diffuse across the junction, recombine and leave charged ions but what I don't understand is why the ions remain fixed around the junction. Surely the...

Hello everyone, Recently I have been studying double layers. As I have studied I have realized that there seem to be a lot of similarities between a double layer and a depletion region in a PN junction. The each form electric fields (and thus have a capacitance) and they each limit (or...

Hi, I have a quick question. When constructing a semiconductor diode, the P-N junction is used to create a depletion region (depleted of mobile majority carriers) which is the active volume of the diode/detector. The region enables an electric current generated from the incomming radiation to...

how does letting the electrons diffuse to the P material/region lead to a "depletion" region in the center where the N and P material meet? please go into detail

Hello everyone, My question is about MOS-capacitor, We know that, If we place +ve gate voltage on p-MOS capacitor holes are repelled from semiconductor-oxide interface leaving behind negative charge due to ionized acceptor ions,This results in a depletion region. Now the question is, If we...

Hi, I am interested in a junction between n doped and intrinsic GaAs, specifically the localization and width of the depletion zone (where the built-in E field is). In a p-n junction the depletion zone is calculated under the condition of electro-neutrality, if I see i-GaAs as really really low...

please explain me -- width of depletion layer varies hey guys, i need to know how does width of depletion layer varies with various factors and i have mentioned all my queries below 1.first of all i want to know how does width of depletion layer increases with decrease in doping content??as...

Homework Statement No actual problem statement. I'm just having trouble understanding what is happening during the depletion and inversion stages. See the attached picture. During the depletion stage, what does it mean by "immobile acceptor ions?" Homework Equations None The...

Hi the first step to this is usually described as diffusion of electrons from the n type to the p type. However I have encountered sites and books that state that holes diffuse from p type to n type as well. I am of the opinion that only the electrons diffuse, and that there is no diffusion of...

Hi. I am reading about the pn junction, but I have a question. When the junction is formed the holes in the p-type material close to the junction diffuse across due to the concentration gradient. This leaves the acceptor atoms in the p-type material negatively charged. My question is: when...

Dear, In Zener Diode, In highly Doped diode,the breakdown(Zener breakdown) occurs in small voltage.How? Thanks& Regards, Viswanathan.M

At depletion layer of p region, there more negative ions thus negatively charged region. Likewise at n region, it is positively charged. Then why in equivalent forward bias the diode behave as a battery of .7v with positive at depletion region of the p region where it is negatively charged?

How the depletion region act as capacitor? My view is that there are no charges because if formed of recombination of charges. so, there is no charge... So, how can it act like a capacitor? How the electric field is created in depletion region? It's confusing me a lot ...

Homework Statement The problem is what would be the effect on the width of the depletion region of an unbiased PN junction on the doping levels of the P and N sides Homework Equations This is a conceptual question. There is no equation involved. The Attempt at a Solution Increase...

So I've become aware that the more "good" choices we make, the easier it is to make a "bad" choice, e.g. if you're on a diet for a couple of months, its very easy to slip and have a piece of chocolate cake, that sort of thing. Here's the wikipedia. http://en.wikipedia.org/wiki/Ego_depletion So...

Hi I'm wondering if anyone has experience working with the triton depletion code for SCALE? I'm having some issues when I'm trying to calculate the activity in radioisotope targets surrounding my reactor core.

Hi, Can someone please tell me if it is true that in heavily doped pn junctions, the electric field that prevents further diffusion of holes and electrons is set up more quickly than in less heavily doped pn junctions? Is this essentially because the holes and electrons recombine more...

For p-n junctions (connected as a junction rectifier), the forward-bias connection (battery's positive terminal connected at the p side) results in a narrowed depletion zone, because: the p side becomes more positive and the n side becomes more negative, thus decreasing the height of the...

in diode why there is creation of depletion region? advanced thanks.

" Depletion Layer is the region in diode which consists of ions( formed due to formation of octet configuration )of p-type and n-type dopants" What happens to the ions present in the depletion layer when a diode is biased? why the depletion layer width changes??

Hello, I am a bit confused about depletion region in NMOSFET transistor. It says here in my book, that when you increase Uds (drain source) above Ugs(gate source) that the current get higher. Ok, makes sense if nothing, from Ohms law. Simultaneously, the depletion region get smaller in...

Homework Statement a. The densities of electrons and holes required for the Fermi levels in both the p- and n-type Ge to enter the bands. That is, in n-type Ge the Fermi level coincides with the bottom of the conduction band and for p-type Ge the Fermi level coincides with the top of the...

Can someone explain to me in detail formation of depletion zone and doping. I thought i understood this but it confused me when it came to this depletion zone. If u dope silicone with a substance with 3 valence electrons this forms a hole right? How does atom then behave? Does it polarize...