Semiconductors Definition and 195 Threads

I am looking for a quick, cheap yet reliable way to count IC's that are in anti-statis shipping tubes. I am thinking of a way to count automatically via a photo or video?

Recently, I have received a referee report on my paper in which reviewer states the following: "... in all known direct band gap semiconductors the electron effective mass is isotropic or has a negligible anisotropy in a comparison with the hole effective mass which can have much more...

I've found channels like this very helpful in the course of my PhD program. I use DFT to study various materials; primarily semiconductors for technological applications. I'm excited to now be a part of PF and I look forward to being a part of the discussion.

My first assumption is that the temperature dependence on the mobilities can be neglected, and so we would have: $$R_H(T)= \frac{1}{e} \frac{p_v(T)\mu_h^2-n_c(T)\mu_e^2}{(p_v(T)\mu_h+n_c(T)\mu_e)^2}$$ The expression for the electron and hole densities could be derived from...

I'm simulating on code the tight-binding sp3s* bandstructure of certain semiconductors, such as GaAs, AlP, InP, ZnSe, etc. with spin-orbit coupling at a temperature of T = 0 K but I'm having trouble at finding the corresponding spin-orbit splitting parameters. For example, I've found in this...

Why is resistivity inversely proportional to resistance for NTC semiconductors?

I heard this while driving the other day. Progress On Perovskite Solar Cells | Earth Wise with Randy Simon https://earthwiseradio.org/podcast/progress-on-perovskite-solar-cells/ I wanted to check this out. Si melts at about 2,570°F (1,410°C). I'm not sure about 3000°F (1649°C), which...

Some post involving diodes made me reconsider pn junctions, with I first learned almost 40 years ago. Coming from a chemistry background, something always felt strange, but I could not tell what. Now I realized: While e.g. Gallium arsenide is a semiconductor itself and can be described roughly...

How NiSi is ohmic contact? Ohm contact occurs when a semiconductor has a lower work function than a metal, doesn't it? NiSi has a larger work function than Ni, so how do you make ohm contact?

It'll soon be time for me to choose my major. I was looking for either an Electrical Engineering or a Computer Engineering major, with a minor in maths. What would be the best to work with semiconductor assemblies, in production or in R&D? And what exactly is the difference between EE and CE...

I would like to plan on a postgraduate studies in Material Characterization - Semiconductor; how difficult is this subject since there are a varity of technques to master them properly in order to join the Semiconductor Industry?

Hello for everyone. I have a question according the field distribution in the semiconductor while the field effect. According to logic, the field is scrreened due to the field of the polarized carriers like electrons and holes. I know about the Debiye length. And that the field on the infinity...

Can Silicon and Germanium semiconductors mixture (chemical reaction) with some other chemical elements (if required) assist in creating new and existing robust electronic components? Si + Ge + ? + ? = Can this assist in quantum computing?

Summary:: What is the advantage of transparent semiconductors such as Fluorine doped tin oxide over main semiconductors? What is the advantage of transparent semiconductors such as Fluorine doped tin oxide (FTO) and Indium tin oxide (ITO) over main semiconductors? Please explain the uses of...

How can we calculate the energy of a hole or an electron in p and n type semiconductors? Which are the contributions from different sources we must take into account? I know it is the dopant and base but if we change one of them how that changes it ? Maybe the interatomic distance has...

Suppose we have a crystal lattice of doped Si with dopant Boron atoms. The energy level of the holes of the Boron atoms are just some eV above the valence band of Si. My question: If we replace all the Si atoms with Ge atoms will the acceptor level change or not? I don't think it will change...

How does the Hall effect work in semiconductors. Since the there aren't enough availabe energy states in the valence band to hold all electrons trying to move due to the magnetic field the Hall effect must be weaker correct?

I am doing experimental research on metal oxide semiconductors and graphene oxide, I also want to do some theoretical analysis. I am new in theoretical, so I need guidance how to proceed with the simple calculations, like DFT. Is there any authentic book with examples? and also is there any...

I'm new to semiconductors. While I was studying types of biasing in semiconductors, here's what I read - 'In forward biasing, the width of the depletion region is reduced.' Here's what I thought - Since the potential barrier is reduced in the junction due to external potential, the diffusion...

When a voltage is applied to a semiconductor at RT, the thermally excited electrons in the conduction band can move freely, similarly the hole that is generated in the valance band. Suppose we drop a voltage across the semiconductor. The electrons in the conduction band moves towards the...

So, let's assume in a theoretical case we have a (semiconductor but not necessarily) device, e.g. a MOSFET, that is perfectly cooled and has zero heat resistance (infinite thermal conductivity), and that it's connected to a perfect heat sink (theoretical abstractions for now, I will come back to...

Assume we have a diode . We connenct the negative terminal of the battery(anode) to the n type region and we connect the positive terminal of the battery to the p type region of the battery.The net force forces electrons to start flowing from the n type region to the p type region.As long as we...

Hi, I have some chemical abbreviation which I do not understand. Please can you tell me what those abbreviations mean? 1. u-GaN 800nm (C:2E16 at/cm3) (I do not understand what "u" stands for; GaN is Gallium Nitride, 800 nm is thickness of layer, C is concentration of atoms per cm3 but I am not...

Hi all - This is pulled from a past paper - Homework Statement I'm only going to state the components that I find challenging of this problem - The rest will be attached in my solution set. Essentially - given an intrinsic semiconductor comprised of group II-VI elements. Upon doping with group...

Hi, I'm an undergrad materials engineering student. I am thinking of studying all the way to a PhD as I'm interested on working in research. Right now I work with Semiconductors and I like the field a lot. However, considering what I'm studying, I want to know if it's a good Idea to look for a...

Homework Statement Homework Equations Energy band diagram equations. The Attempt at a Solution This is more of a conceptual question, but this is the problem I am working on for reference. What is the difference between a flat band diagram and an equilibrium diagram? I know what they will...

Is the equation used to determine the density of interface states in schottky diodes from capacitance- frequency data applicable to PIN junctions?

Homework Statement A sample of Si at room temperature is doped with acceptors at a concentration of 3E16 cm^-3. An excess electron hole pair density of 1E14 cm^-3 is generated at some time t = 0. At t = 13.9 μs the excess EHP density is measured and found to be 5E13 cm^-3.(A). Does the initial...

Homework Statement This isn't really a problem, but I wanted some clarification on this topic. In an energy band like the one I drew below, what determines the size of the conduction band and valence band? Etop - Ec and or Ev - Ebot? Is that just a property of the material? Also, how do...

Homework Statement Homework Equations The Attempt at a Solution I am having problems with all parts of this problem, but I'll start with part A. Comparing the 2 equations I see that Ca could be 3/2 based off the hint, but I am not sure why or how it would be 3/2 or -3/2. The problem...

What protocol should I use to get a good stable 100nm Au adhesion onto a Si substrate using electron beam evaporation? I've heard talk of primer layers of either Cr or Ti at around 5nm thickness, as the typical way to do it. Which material should I choose? What the advantages or disadvantages...

Does anyone know of a good resource for semiconductor physics? I can't find much for it and the textbook isn't much help. Here is a https://filebin.net/8navybb1hnt50wi9/Formulae_2017.pdfandhttps://filebin.net/8navybb1hnt50wi9/Formulae_2017.pdfthe textbook is an introduction to semiconductor...

What is the reason for enhancement in the intensity of emission due to the introduction of a shell in quantum dots? I do understand the blue shift in quantum dots but how does a shell enhance it?

I have a pressing question, but I don't exactly know how best to articulate, or where. I am a wafer fab operator in the semiconductor industry. I usually operate ion implanters. The highest energy ion beams we use are a little over 3.5 MeV. As an aside, I am looking for a way, given that, to...

In a cylindrical symmetry domain ## \Phi(r,z,\alpha)=\Phi(r,z) ##. Does anyone can point me what can be found in literature to solve, even with an approximate approach, this equation? \nabla^2 \Phi(r,z)=-\frac{q}{\epsilon} \exp(-\frac{\Phi(r,z)-V}{V_t}) Where ## q, \epsilon, V ## and ## V_t ##...

In "Sado Adachi" book "Properties of Group-IV, III–V and II–VI Semiconductors" page 222, he reported that "both εs and ε∞ decrease almost linearly with increasing pressure", however i was not able to find any empirical formula to describe these relationship for materials InAs, InP, InSb, where...

I was studying about Crystal defects in crystals and came to know that it has huge effect on band diagram.I don't know about their specific impact on band diagram.So what are major impacts of crystal defects on band diagram.?

Hello, I was wondering if there is any way of increasing a transistor or thyristor maximum voltage ratting in DC? Thanks. Edit: Just to be more precise, I am referring to the off state. I know you can the on state via a resistor.

Can combination elements in group I and group VII be a semiconductor? My thinking is that they form the octet rule just like group II and group VI elements.

Are there insulator quantum dots or conductor quantum dots?

Is there a list of semiconductors that are heavy metals?

My teacher told me the other day that a semiconductor does not have a fermi surface. I didn't understand this remark. As I understand it the Fermi Surface is just the surface in k-space spanned by the highest occupied energy levels. Surely in a semiconductor you will also have some highest...

Soon our ability to continue making ICs more dense will end and we will be forced to come up with new technology for greater speeds and calculating power. In your opinions, what is the most likely technology that will replace (or be integrated in with) semiconductor chips? Photonics...

Hi all, I'm reviewing device physics and I would like to understand how majority and minority carrier concentrations for both N- and P-type substrates change with temperature. My reference, Pierret's Semiconductor Device Fundamentals, has this figure: and I want to generate curves for all...

hi, I would like to be bursting with semiconductors' topic, I aim to know all it's theory and applications, also see all derivations of it's formulas, so Could you give me some suggestions to comprehend this topic well?

Hello! In order to obtain the number of actual electrons in the conduction band or in a range of energies, two functions are needed: 1) the density of states for electrons in conduction band, that is the function g_c(E); 2) the Fermi probability distribution f(E) for the material at its...

Hi! When dealing with a pn homojunction, it is easy to see the features it has at equilibrium, and also the features it has with forward/reverse bias. Plots show the constant Fermi level at equilibrium and the different Fermi levels for a forward bias; moreover, examples show how much the bands...

Hello! The (potential) energy of an electron in a solid structure is always negative; also the E_c and E_v levels (conduction band and valence band limits) are negative, in the band diagram of a pn junction. When the junction is built and thermal equilibrium is reached, the depletion region...

Hi all, new poster here, I graduated First Class with a BS and an MS, specialisation Electronics, from Calcutta University, scoring University highest grades in my special paper, Electronics. Since then, for the past 15 years, I have been teaching at various schools, colleges, and currently an...

How can i calculate this plot (photon energy dependence of the optical gain (or loss = negative gain) of GaAs with the injected carrier density as a parameter? Show calculated plot based on this equation Given parameter: mc=0.067 me; (effective mass of electrons in conduction band) mv=0.48...